NeuroScience2013

2013年11月9日～13日にアメリカのサンディエゴで開催されたNeuroscience2013にて8名が研究発表を行いました。
発表タイトル
●山本詩子助教「Fiber tractography based on curvature and torsion for fibers
crossing area」
●井上楓彩「Effect of sound pressure level on brain function during memory
task using fNIRS」
●大西夏子「Discussion of brain functional on the effects of color
temperature on sustained attention using functional near-infrared
spectroscopy」
●木村茜「Impact of sustained attention on difference between visual and
auditory stimuli」
●杉田出弥「Effect on brain function in inhibitory control during go/no-go
tasks caused by changes in difficulty」
●早川温子「Brain function imaging using functional near-infrared
spectroscopy for the development of training: A study on ability
differences in stereopsis」
●将積彩芽「Gender differences in influence of sound environments on
performance of the memorizing numerical string task and cerebral blood
flow changes」
●真島希実「Analysis of working memory using the reading span test: Basic
research of regional brain activity on brain cortex using functional
near-infrared spectroscopy」
今回参加した大学院生のみなさんは国際学会で発表するのが初めてで、発表前や初めは自分の研究を英語で伝えることにとても緊張していましたが、発表時間が終わる頃には皆活き活きと自分の研究を紹介し、英語でコミュニケーションすることを楽しんでいました。
どのようにすれば自分の研究を初対面の方に伝えられるか、各自で考えて工夫することができており、学生のみなさんにはとても有意義で貴重な経験になったと思います。
学会が開催されたサンディエゴは京都と同じくらいの気温で過ごしやすく、日が暮れても繁華街を歩けるほど安全な町でした。発表を終えた後に学会会場であるコンベンションセンターの屋上から見た夕日は忘れられない感動的なものでした。これからも研究活動に勤しんでいこうという勇気と活力を得られました。
【文責：山本助教】

 
1. 講演会の詳細
2013/11/09から2013/11/13にかけて，アメリカ，カリフォルニア州，サンディエゴのサンディエゴコンベンションセンターにて開催されましたNeuroscience2013に参加致しました．このNeuroscienceは，SOCIETY for NEUROSCIENCEによって主催された研究会で，脳や神経系の理解を深めることを目的に開催されています．
本研究室からは他に山本先生，木村，將積，杉田，大西，眞島，井上が参加しました．
 
2. 研究発表
2.1. 発表概要
私は13日の16:00 – 17:00のセッション「Extrastriate Cortex: Functional Organization」に参加致しました．発表の形式はポスター発表でした．
今回の発表は，fNIRSを使用し，脳血流変化から立体視の得意・不得意による能力差及び習熟度の検討を行いました．以下に抄録を記載致します．

[Purpose] In this research, an evaluation method for proficiency assessment using brain functional mapping information is has been established using information obtained after mapping brain function. The target task in this paper is stereopsis. [Methods] To accomplish the goal of this study, we investigated two subject groups. These groups were divided by on the basis of whether the or not subjects were good at stereopsis or not. Then, we compared the difference of in cerebral blood flow change between the groups. The blood flow change was measured by using functional Near-Infrared Spectroscopy (fNIRS), which is known as high time resolution. Then, we examined the progress of stereopsis from its analyzing the fNIRS data. As a training task, the subjects were shown some stereograms, in which they can find one Japanese character (Hiragana).The subjects were measured their cerebral blood flow changes in subjects were measured using fNIRS when they were engaging with stereoscopic vision using fNIRS, and We counted the number of stereogram sheets which that subjects were able to recognize in a limited time frame was counted. This number is defined as proficiency. We The study involved had eleven volunteer subjects. [Results and discussions] Firstly, we classified subjects into two groups on the basis of whether or not the subjects they were good at stereopsis or not. Secondly, to examine the active region, we divided rest and task section data into fifteen pieces, for which baseline processing was performed through the all the channels (CH), into fifteen pieces. Then, these pieces were analyzed using performed t-test (p < 0.01).As the result, for almost all the subjects, there was a significant difference in three CHs near the lower frontal head of almost all subjects. Then, we chose selected these three CHs and the other CHs, where the significant differences were found as interested regions. We calculated the average amount of cerebral blood flow change in the CHs. Finally, we figured out observed the average sites where of focused site of cerebral blood flow changes occurred. The decrease of the change was found at the subjects who were good at stereopsis showed a decrease in cerebral blood flow change. In the Other related studies, it is reported that the change of in the dorsolateral prefrontal cortex (DLPFC) were decreased with the progress of stereopsis ability. Therefore, in this study, we concluded that the region of interested region in this study might be DLPFC. In these related studies, the personal ability differences were not mentioned. Since our results are similar to the related study, it we may conclude that DLPFC is related with to the personal ability differences.

 
2.2. 質疑応答
今回の講演発表では，以下のような質疑を受けました．
・質問内容1
質問者の氏名を控え損ねてしまいました．立体視とは何か，立体視の方法はという質問や，4週目だけなぜ増加してしまったのかという質問を頂きました．立体視とは何かという質問には，平面の画像から立体的な像を知覚する方法であると回答しました．また，立体視の方法については，実際にステレオグラムを持っていたので，それを使用しながら説明を行いました．言葉では，自分の目の焦点をステレオグラムの奥に合わせるようにすると説明しました．最後の質問には，実際何が起こってこの結果となったのか不明であったため，難しい質問で私も答えが分かりませんと答えました．また，それに加え，これからの実験では4週以上実験を行ったり，アンケートを使用すると答えました．
 
・質問内容2
質問者の氏名を控え損ねてしまいました．他の被験者のデータはどうなっているのかという質問を頂きました．この質問には，事前に準備しておいたデータを添付したスライドを見せながら，ポスターに載せた被験者以外の被験者も同様の傾向になったと説明しました．
 
・質問内容3
質問者の氏名を控え損ねてしまいました．不得意な被験者を訓練したら得意な被験者と同様の脳血流変化になるのかという質問を頂きました．この質問には出来る被験者と同様の結果になると答えました．実際に，ポスターに載せた能力差に関する結果と習熟度に関する結果を見比べると被験者は異なりますが，不得意な被験者は得意な被験者と同様の傾向を示すようになるのではないかと考えられました．
 
・質問内容4
質問者の氏名を控え損ねてしまいました．13枚か14枚あたりになったら訓練は終了なのかという質問を頂きました．この質問に対する回答では，私の使用しているプログラムの関係上そこが最高枚数になると答えました．
 
・質問内容5
質問者の氏名を控え損ねてしまいました．質問は，なぜこのような実験設計にしたのか，レストで発話と注視を行っているのはなぜかという質問を頂きました．この質問には，英語でどのように答えていいか分からず，質問してくださった方にあまり理解して頂けませんでした．タスク中に被験者に発話し解答してもらうこと，また立体視を行う際に画像を凝視するため注視をすることの2つの影響を消すために行っていると答えたかったです．
 
・質問内容6
Donders Institute for Brain, Cognition and Behaviour, Behavioural Science Institute, Radboud University Nijmegen, Nijmegen, Netherlands所属のAtsuko Takashimaさんからの質問です．こちらの質問は，なぜ4週目だけ増加するのかというものでした．また，他の被験者については同様の結果となったのかという質問を頂きました．この質問に対する私の回答は，最初の質問では質問内容1と同様なぜこのような結果となったのか分からないと答えました．すると，反応時間や正規化し，集団解析を行うこと，また，集中度を計測できる指標について相関を見ることなど様々な意見を聞かせて頂きました．2つ目の質問には，データを添付したスライドを見せながら他の被験者も同様の傾向を示したことを説明しました．
 
・質問内容7
東北大学電気通信研究所 所属の栗木 一郎さんからの質問です．こちらの質問は，このような実験設計にしたのはなぜかという質問を頂きました．また，群分けで5枚以下の被験者を不得意としたのはなぜかという質問を頂きました．最初の質問に対しては，タスク中に被験者に発話し解答してもらうこと，また立体視を行う際に画像を凝視するため注視をすることの2つの影響を消すためであると答えました．すると，レストで立体視の出来ないステレオグラムと似た画像を被験者に見てもらうなどもう少しレストとタスクで行うことを合わせたほうがいいのではないかという意見を頂きました．2つ目の質問には，実験設計を見ながら，説明を行いました．
 
・質問内容8
質問者の氏名を控え損ねてしまいました．質問は，fNIRSとは何か，また計測原理はという質問を頂きました．最初の質問には，近赤外光を用いて脳血流変化を計測できる装置であると説明しました．次の質問には，事前に用意していたNIRSの計測原理を示したスライドを使って説明しました．
 
2.3. 感想
初めての国際学会であったこともあり，とても緊張しました．また，私は英語が苦手であるため，きちんと英語で説明出来るか，質問に答えられるかが不安でした．しかし，いざ発表が始まってみるとどうにか英語で答えることも少しは出来ていたのではないかと感じました．また，質問をくださる方が優しかったため，私が英語を聞き取ることが出来ずに困っていたり，質問に対する答えになっていない時などには違う言葉で言い換えたり，図を指しながら質問して下さったり，また，私が質問を理解できるように質問で誘導して下さったりして頂きました．さらに質問だけではなく，様々な意見をくださる方もいたため，研究に対するモチベーションが上がりました．機会があれば，また国際学会に参加したいと思います．そのためには，さらに研究を進める必要があるため精進していきます．
感想には英語で説明出来たと書きましたが，私の英語力は未熟であるため，英語をもっと勉強し，聞き取りやスピーキングの能力を向上する必要があると感じました．また，質問者のお名前を控え損ねてしまったことも反省点の一つです．
 
3. 聴講
今回の講演会では，下記の7件の発表を聴講しました．
 

発表タイトル       ：　Dynamics based neural coding in the subjectivity context著者                  ： K.Mogiセッション名       ： ++F.01.t. Timing and temporal processingAbstract            ： Dynamics is an essential element in the coding of information in the brain (Stein et al. 2005). In analyzing neural codes, the conventional approach has been to apply statistical methods such as signal detection theory (Swets 1964) or integrated information theory (Tononi 1998). Such an approach has provided useful insights into the functions of the brain and principles of perception and cognition. A statistical approach can be enhanced further by incorporating the dynamics and structure of the system explicitly. Key to such a treatment is the explicit and dynamic choice of the “ensembles” with which the statistical properties of a system are analyzed. A number of experimental data and theoretical analysis have suggested that perception is an active process, where the hypotheses and internal models based on past experience are “matched” with the incoming sensory data. It is thus likely that the dynamic choice of ensembles by the cortical neural network is implemented in this matching process. Here I present an analysis of the necessary conditions for the construction of a dynamics based neural coding, citing relevant evidence from the measurement of neural firings in the brain. Strategies for the study of neural information processing in the era of big data on brain anatomy and function are presented. A model for dynamics-embedded ensemble formation is presented, with the subjectivity structure explicitly given. In this model, time is an essential element constructed actively, on which a spectrum of neural codes are defined. Psychological time generated from the neural activities is in general different from the physical time. It is proposed that the excitatory, inhibitory, and modulatory connections within the neural network contribute to the construction of subjective time in different manners. Finally, I discuss how the semantics of information can be implemented in a coding system based on dynamics and embedded in the subjectivity context.

この発表はアブストに書いてある内容と大きく異なるものでした．茂木先生曰く，アブストに書いた内容の研究ではあまり面白い結果が出なかったため内容を変更したとのことでした．先生の研究は，時間の知覚，即ち定性的な時間と定量的な時間の感じ方についてでした．タスクの難易度に関係した研究だとおっしゃっていました．難しいタスクを行うとタスクにかかる時間は長いと感じるそうです．即ち，定量的な時間は短いということでした．以上のことから時間と感覚が連動している脳の部位があるのではないかと考えられているそうです．この場合，タスクの種類や個人のタスクの難易度の感じ方でも違いが出てしまうということが欠点であるため，熟考するとのことでした．
 

発表タイトル       ：　Real-time neuro-feedback training of executive functions in healthy adults: A functional NIRS study著者                  ： H. HOSSEINI, S. R. KESLERセッション名       ： ++F.01.l. Executive functionAbstract            ：Cognitive training is an emergent approach that has been adopted in recent years as a potential intervention for a number of developmental and neurodegenerative disorders. Cognitive training theoretically promotes several neuroplastic mechanisms in the brain and has been shown to improve cognitive functioning in various healthy and patient populations. The main goal of cognitive training is to boost/restore cognitive skills and brain function by employing a set of adaptive, practice-based paradigms. In order for the training programs to be effective, individuals are usually asked to perform a distributed set of cognitive training paradigms. This approach has several disadvantages. First, the training time can be lengthy (1 to 6 months), making adherence potentially difficult for patients with cognitive difficulties. Second, there is no guarantee that the training will be helpful for a specific individual. Third, the efficacy of the training is usually tested after the end of the training neglecting potentially interesting learning effects at other time points. In the present study, we developed a real-time neuro-feedback training program that addresses some of the limitations of conventional training methods by providing real-time feedback regarding brain activity in targeted regions. We focused on training executive functions (EFs) given their core involvement in various developmental and neurodegerative diseases. Near-infrared spectroscopy (NIRS), which is a cost-effective and ecologically-valid brain imaging method, was employed for measuring brain activity in the prefrontal cortex. Our preliminary data on 10 healthy adults (5 female, age range 18 to 40) showed four sessions of EF training (100 min total) with neuro-feedback significantly improved EF. Specifically, subjects’ performance on standardized EF tests including measures of verbal and visual working memory as well as inhibition/switching were significantly improved (p < 0.05). In addition, we compared the neuro-feedback training results with those of a parallel study in which we examined the effect of computerized EF training (24 sessions each lasting 20 min in 6 weeks) on 18 healthy subjects (9 females, age range 18 to 40). Despite the significantly lower duration of the neuro-feedback training (100 min vs. 480 min), the increase in inhibition/switching performance was slightly higher in the neuro-feedback training group compared with the computerized training group. Our data suggest that providing neuro-feedback may improve the efficiency of cognitive training paradigms making it more feasible for certain patient populations.

この研究は，外国の方がfNIRSを使用していたため興味を持ちました．fNIRSは日本では普及してきていますが外国ではあまり普及していないイメージであったため面白そうだと感じました．fNIRSを使用してニューロフィードバック活動とパフォーマンスの相関を検討していました．言語記憶課題である4つのタスクを使用して各タスクとパフォーマンスの相関を考察していました．
 

発表タイトル       ：　Personality traits and underlying neural circuits for reward processing: An fMRI investigation著者                  ： M. TSCHERNEGG, M. KRONBICHLERセッション名       ： ++F.03.i. Motivation and emotions: RewardAbstract            ：Reward-related decisions are ubiquitous in our daily lives. Recent functional neuroimaging studies showed that nucleus accumbens, medial orbitofrontal gyrus and amygdale are responsive to reward outcomes. Mental disorders, characterized through changes in reward system-related brain structures (e.g., depression or addiction), show divergent activation patterns in current research. Non-pathological differences in personality are also likely to show divergent reward-related activation. Since previous studies separated approach and avoidance motivated groups and found differences in the reward system, this study aims to provide further interpretation including personality traits (e.g., sensation seeking), and self-regulation abilities (e.g., risk taking and impulsivity). The monetary incentive delay task (MID) and the card-guessing task are common paradigms for investigating reward-related neuronal circuits. These tasks are known to activate the mesolimbic dopaminergic system by offering win-situations for fast reactions or correct guesses. The present study tests the validity of a modified and simpler MID for investigations of reward outcome. By excluding workload confounds by presenting two different cues (win vs. no-win) and two different outcomes per cue (win or no-win vs. fast and no-fast), we hope to facilitate the interpretation and provide stronger results for further investigations. Additionally, we employed the card-guessing task while fMRI to localize reward-related neuronal circuits (independent from MID) and a Go/No-Go task while fMRI for identifying impulsivity-related structures. As expected, the modified MID and card-guessing task yielded increased activation for reward outcome regions such as the bilateral ventral striatum and orbitofrontal gyrus (p<0.05, FWE). This result serves a solid basis for an investigation of neural substrates for personality traits. Hyper-, or hypo-activation in reward-related brain regions is not clearly assignable for most of the mental disorders. The “impulsivity hypothesis” (excessive sensitivity to reward and failure of inhibition) or the “reward deficiency hypothesis” (reduced response to non-drug rewards and drug seeking) explain reward-related neuronal changes in mental disorders equally well. By additionally assessing personality traits we hope to characterize the missing link to dissociate these two hypotheses more precisely.

これは，報酬に関わる研究でした．様々なゲームにおいて勝ち負けで脳の活性部位がどのように変化するか検討していました．勝つことで被験者は快に感じることで脳の活性部位が変化すると考えていました．結果としては，個人によりその活性する脳部位が異なることが分かっていました．ゲームの勝ち負けでの脳の活性部位の変化を調査している研究は面白そうだと思いました．また，様々なゲームを行っていたのも楽しそうだなと感じました．
 

発表タイトル       ：　Test date expectancy affects memory performance著者                  ： R. E. LOIOTILE, R. A. ADCOCK, S. M. COURTNEYセッション名       ： ++F.01.g. Human long-term memory: EncodingAbstract            ：Though several studies have examined the role of test expectations– e.g. expectations of test type and test consequences– on subsequent performance, surprisingly little is known on the role of test date expectations, specifically. Knowledge of test dates certainly affects how students distribute their study time, a learning factor that has been investigated since the birth of memory research. But, irrespective of study-time distribution, does knowledge of the expected test date affect one’s encoding of the material? Our study, therefore, seeks to determine the effects of expected test date on memory performance. We hypothesized (1) that individuals would alter their learning strategies, perhaps even unbeknownst to themselves, to benefit expectations of longer retrieval delays or (2) that certain test dates– e.g., those closer to the present– would induce differential pre-learning motivation or preparedness to learn. Our experiment tested recognition on a set of 120 emotionally neutral scene stimuli in twenty subjects. Subjects were informed that half of the stimuli would be tested today (i.e., 30 minutes after encoding), half would be tested tomorrow (i.e., 23-25 hours after encoding), and that they would be informed of each scene’s test date by a pre- (and during-) scene cue reading “today” or “tomorrow.” Critically, subsequent recognition tests ignored the advertised test dates. Subjects were tested on half of the stimuli from each test-date cue on each test date. For example, 30 today-cued scenes were tested at “today,” and the remaining 30 today-cued scenes were tested at “tomorrow.” Analysis revealed a significant main effect of cue date on memory performance. On average, subjects remembered today-cued stimuli better than tomorrow-cued stimuli on both “today” and “tomorrow” tests, with the latter showing a significant difference. Our results indicate that despite monetary incentives to perform as well as possible on both “today” and “tomorrow” tests, independently, subjects were more motivated– some admittedly, others unknowingly– to memorize the stimuli they thought would be appearing on “today’s” test. Future fMRI work will attempt to ascertain the neural mechanisms of this differential memory performance. In particular we would like to examine whether today-cued stimuli, independent of memory performance, are correlated with differential increases in midbrain activation, similar to cuing effects of expected monetary rewards. Overall, our study demonstrates a strong effect of test date expectations on learning, independent of study time and distribution.

この研究は，記憶タスクを使用したものでした．しかし，私の英語の理解力が不足しているためタスクの細かい内容を聞くことが出来ませんでした．ワーキングメモリーを検討するタスクで有ると思いましたが，他の人のタスクでは見たことない内容だったので興味深かったです．もう少し英語を勉強して分からない所があれば自分から質問することができるようにしたいです．
 

発表タイトル       ： Facilitatory role of playing music during exercise in executive function: A neuroimaging study with functional near-infrared spectroscopy著者                  ： K. SUWABE, I. DAN, K. HYODO, K. BYUN, G. OCHIセッション名       ： ++F.01.l. Executive functionAbstract            ： The benefits of acute and chronic exercise on human cognitive functions have been given a great deal of attention. One of our recent studies has shown for the first time that acute moderate exercise (at 50% VO2peak) elicits increased brain activation in the left-dorsolateral prefrontal cortex (DLPFC), which results in improved Stroop task performance (Yanagisawa et al., NeuroImage, 2010). The DLPFC plays a role in the modulation of mood as well as executive function: activation in the left DLPFC enhances positive emotional affects (Ueda et al., 2003; Herrington et al., 2005). Hence, it is postulated that listening to one’s favorite music while exercising may elicit greater activation in the DLPFC, leading to enhanced executive functions. To address this issue, twenty-six subjects (mean age 21.6 ± 2.4 years, 8 females) participated in two experimental conditions (exercise with music or with a beep at a steady tempo). Subjects performed a color-word matching Stroop task (CWST) and two-dimensional mood scale (TDMS) before and after 10 minutes of moderate intensity exercise (50% of VO2peak). Using multichannel functional near-infrared spectroscopy (fNIRS), cortical-activation-related changes in the CWST were examined. Results demonstrated that the music condition evoked a more positive valence compared to the tempo condition. However, no significant differences were observed between the two conditions in CWST performance or Stroop-interference-related activation in any prefrontal regions. Interestingly, there were positive correlations between valence changes and CWST performance changes, and valence changes and cortical activation changes in the left DLPFC. These results suggest a facilitatory role of playing music during moderate exercise in the development of enhanced executive functions induced by exercise.

この発表では，fNIRSを使用していたため興味を持ちました．また，我々はfNIRSで脳血流変化を計測していますが，この研究では，局所脳血流を計測していました．fNIRSで局所脳血流を計測するということが新しいなと感じました．研究内容としては，fNIRSを使用して，運動が認知機能とどのように関係しているかを神経活動より検討していました．体力レベルの向上など健康維持に役立つ研究であるとおっしゃっていました．また，運動を行っている際には音楽をかけることで被験者の気分が良くなることで脳の活性が向上するのではないかを検討していました．
 

発表タイトル       ： Consolidation of newly learned words: Does the presence of pictures at encoding make a difference?著者                  ：A.TAKASHIMA, I.BAKKER, J. G. VAN HELL, G. JANZEN, J. M. MCQUEENセッション名       ： ++F.01.f. Human long-term memory: RetrievalAbstract            ：From lesion and imaging studies, we know that memory is not a unitary system. Declarative memory is considered to entail episodic memory (memory for episodes that are confined to specific spatial and temporal contexts) and semantic memory (memory for generic knowledge or concepts). Although these two types of memories are not independent and highly interactive, they seem to involve different brain structures at retrieval, with the hippocampus often regarded to be important for retrieving arbitrary associative information encoded in a specific episodic context, whereas widely distributed neocortical areas, especially higher order associative areas, seem to be important in retrieving semantic or conceptual information. In this study, we were interested in the neural correlates of newly learned words when retrieved at different time points. We asked if there is more involvement of the episodic memory network when retrieval occurs directly after learning, and if there is a shift towards more involvement of the semantic network as the word becomes more de-contextualized with time. Furthermore, we were interested to see the effect of having extra information at encoding, namely, visual information associated with the phonological form of the novel word. Previously we have reported that picture-associated novel words retrieved immediately after encoding involve hippocampal structures more than phonological form-only words. When retrieval took place 24 hours later, the involvement of the hippocampal system was still present for the picture-associated words, but involvement of distributed neocortical areas also increased with time. In the present study, we extended the delay from 24 hours to 1 week. Participants learned phonological novel word forms with/without corresponding pictures and their memory for the words was tested in an fMRI scanner. Retrieval success was greater for picture-associated words compared to phonological form-only words on both recent and remote test. When memory for the associated picture of the word was tested, exactly the same pictures were recognized faster than similar pictures at both time points, but at remote test we also observed an interaction. Specifically, although recognition of the same pictures slowed down as a function of delay, this was not the case for similar pictures, indicating decay of the episodic memory trace and some de-contextualization of the word memory. On the neural level, the memory benefit of having pictures at encoding was observed as more involvement of the hippocampus during recent retrieval, and increased activity in the fusiform gyrus and the left angular gyrus during delayed retrieval.

この発表では，訓練をした後の学習について検討しているものでした．私がこの研究に興味をもったのは，自分と似たような所にポイントがあったためです．私は訓練に伴う習熟度を検討しているため，学習などのテーマに興味を持っていました．また，この研究の実験結果は，私の研究の結果と似たような結果となっていたため興味深かったです．研究内容は，fMRIを使用して，学習のシステム，ネットワークを検討していました．文字だけで覚えるのと絵も加えて覚えるのとではどのような変化が生まれるか検討していました．
この発表者の方には私の実験結果について少しお話することがあり，後日私の発表の際にポスターにお越し頂きました．
 

発表タイトル       ：　The impact of sensorimotor experience on affective evaluation of movement著者                  ： L. KIRSCH, K.A. DROMMELSCHMIDT, K. DAWSON, E.S. CROSSセッション名       ： ++F.01.a. Perception and imageryAbstract            ：Prior research on aesthetics demonstrates that people are more likely to judge a stimulus as pleasing if they are familiar with. While general familiarity and liking appear to be related, it is less clear how motor familiarity, or embodiment, is related to a viewer’s aesthetic appraisal of a stimulus. Previously, we demonstrated that people derive greater pleasure from watching movements they are not able to embody compared to those they felt they could. To more closely investigate this finding, we subsequently conducted two dance training experiment to clarify the relationship between sensorimotor experience and affective evaluation of a movement. The first experiment used a between-subjects design wherein 62 participants were assigned to one of three groups and took part in four days of training. One group received physical training on simple dance sequences with the Xbox KinectTM system, another visual and auditory training, and a third group received auditory experience only. Participants’ aesthetic preferences for different dance stimuli were measured with a rating task before and after the training sessions. Results demonstrate that participants from the physical training condition not only improved their performance of the dance sequences, but they also reported higher enjoyment and interest in the sequences after training. These results suggest that learning to embody particular movements can indeed lead to greater enjoyment while watching those movements in the future. The second experiment is an fMRI version of Experiment 1 that directly compared how learning to embody an action impacts the neural response when watching and aesthetically evaluating that action. Using a within-subjects design, 24 participants trained for four consecutive days on dance sequences set to music videos. Each day they physically rehearsed one set of dance sequences, passively watched a second set of sequences, and listened to the music of a third set. Functional MRI was obtained prior to and immediately following the four days of training, as well as affective and physical ability ratings. This approach enables us to examine the brain basis of how action embodiment is related to the pleasure a viewer derives from watching an action. Moreover this study enables a precise comparison of self-report methods of embodiment with non-biased, empirical measures (e.g., scores given by the participant vs. the Kinect system). Together, these two studies are the first to use intensive training procedures coupled with fMRI to investigate affective judgment in relation to embodiment, and will inform both affective and motor research areas.

この研究も日を追うごとに訓練を行い，そのスコアについて，またfMRIで学習に関する脳部位を検討していました．課題は，kinectを使用したダンスパフォーマンスでした．
 
参考文献
1)    Neuroscience2013, http://www.sfn.org/annual-meeting/neuroscience-2013
 

 
 
 
1. 講演会の詳細
2013/11/09-2013/11/13にかけて，San Diego Convention Centerにて開催されましたNeuroScience2013（http://www.sfn.org/annual-meeting/neuroscience-2013）に参加いたしました．このNeuroScience2013は，The Society for Neuroscienceによって主催された集会で，“脳と神経系の理解を進め，種々の背景の科学者，研究の統合の促進”というメインテーマをもとに，脳と神経系の理解をすることを目的に開催されています．
私は，9-12日は公聴，13日に発表いたしました．本研究室からは他に山本先生，杉田，大西，真島，井上，早川，將積が参加しました．
 
2. 研究発表
2.1. 発表概要
私は13日の午前のセッション「Mechanisms of Attention」に参加いたしました．発表の形式はポスター発表で，ポスターの掲示可能時間が4時間となっておりました．
今回の発表は，ポスター発表です．以下に抄録を記載致します．

[Purpose]In the field of functional mapping of the brain, several experiments were performed by observing the effects of the provided stimuli on subjects.　 However, the same reactions could be related to different stimuli leading to different processes of higher brain functions and different activity states.  Therefore, to associate cerebral function with a particular activity state of the brain, it is necessary to take into consideration the difference in the activity state induced by different stimuli.  In this study, we used visual or auditory stimuli during the psychomotor vigilance task (PVT) and the go/no-go task, which are commonly used for measuring the same sustained attention. In addition, we examined the effect of these different stimuli on cerebral blood flow changes or reaction time (RT).[Methods]This experiment measures the inferior frontal gyrus of 34 healthy men performing four types of tasks using functional near-infrared spectroscopy.It has been observed that focused regions are activated when a subject performed these tasks.  The change in total hemoglobin concentration between the rest and task periods was calculated for every subject and compared using Student’s t test (p < 0.05).  The regions which had a significant difference in both visual and auditory stimuli were regarded as active regions.[Results]Subjects were classified into two groups on the basis of the changes in concentration at audio and visual stimulus.  In V group, changes in concentration at visual stimulus were larger than that at auditory stimulus. In A group, the changes in concentration at auditory stimulus were larger than that at visual stimulus.　 In PVT, no difference was observed in RT between V and A group.  In contrast, ingo/no-go task, the A group was approximately 20 ms later than V group.[Conclusions]It has generally been recognized that more the information input in the brain, more activated the brain is.  It is believed that visual stimuli contain more information and induce more load on the brain than auditory stimuli.  However, the A group was activated while performing audio stimulus.  These results suggest that the A group was unable to pay attention to the visual stimulus, which had more information.  Moreover, the amount of information of the go/no-go task is bigger than that in PVT.  Therefore, difference in the activity state of the brain in visual and auditory stimuli was more evident in the go/no-go task.

 
2.2. 質疑応答
今回の講演発表では，以下のような質疑を受けました．
・質問内容1

質問者の氏名を控え損ねてしまいました．こちらの質問は，注意によって総Hbが増加するかは未明，部位によっては減少するかもしれないよね？というものでした．この質問に対し私は，その通りです．今回は使用装置の特性で総Hbしか見ることができなかった．今後Oxy-HbやDeoxy-Hbも一緒に脳全体で見ていきますと回答しました．

 
・質問内容2

質問者の氏名を控え損ねてしまいました．こちらの質問は，sustained attentionを計測するには課題時間は短いのではないか？というものでした．この質問に対し私は，その通りです．Sustainedというよりはalertingの計測になってしまったかもしれない．被験者が眠らないようにするために短い課題にした．と回答しました．すると，僕は課題の合間に被験者に「課題を始めますよ」などこまめに声をかけて眠らないようにしているよとアドバイスを頂きました．

 
・質問内容3

質問者の氏名を控え損ねてしまいました．こちらの質問は，マルチモーダルな刺激ではやっていないの？というものでした．この質問に対し私は，やっていません．今後やっていきたいですと回答しました．すると，僕も同じように視聴覚を今後比べようと思うのだけれど難しい，何を計測するか考えることが重要だとアドバイスを頂きました．

・質問内容4

質問者の氏名を控え損ねてしまいました．こちらの質問は，視覚刺激と聴覚刺激の難易度はそろっているのか？比較していいものなのか？というものでした．この質問に対し私は，課題の平均反応時間が聴覚＜視覚となっているので課題の難易度的にいいと判断したと回答しました．しかし，GO/NOGOの視覚刺激と聴覚刺激の平均反応時間にあまり差はなかったので，今後課題設計を行う際には視覚刺激と聴覚刺激の平均反応時間に差のあるような課題設計にしなければならない

と感じました．

 
・質問内容5
質問者の氏名を控え損ねてしまいました．脳血流変化は信号として一番最後の信号，本当に視覚と　聴覚の影響・干渉を比較できるのか？
細かい信号を見るのではなく全体の大きな活動を探る
2.3. 感想
「注意」のセッション，「注意」の発表が驚くほど多くあり，同じテーマを研究している多くの研究者の中で発表し，意見やアドバイスを頂けたことは本当に為になりました．ただ，やはり言語の壁を感じ，つい日本人研究者には日本語で説明してしまい，海外の人との交流時間が減ってしまったことは後ですごく後悔しました．
他の研究については，視覚刺激と聴覚刺激の課題間の差を考慮せず左右半球の活動特性を研究などもあり，私の研究の大切さも分かったように思います．また，「注意」以外で，注意や全ての脳機能に関係のあるresting stateやdefault mode networkなどの研究などもたくさんあり，すごく勉強になりました．
そして，何百枚何万枚とあるポスターを見ているうちに，伝え方によってどんなに素晴らしいだろう研究も意味がわからなくなり，それほど進んでいない研究でもすごく見えました．今まで，自分が伝えたいことや書いておかなければいけないと思い込んでいたもの等を，自分目線でポスターやパワーポイントを作っていましたが，いかに聴衆のために客観的な視点から作れるかが重要であると気づきました．
 
 
3. 聴講
今回の講演会では，複数の発表を聴講しました．
 

発表タイトル       ：　Immediate effects of anterior thalamic stimulation on human cognition and emotion

著者                  ： L. SUN¹, M. POLVIVAARA¹, M. BRAUSE¹, K. LEHTIMAKI², J. PELTOLA², *K. H. OGAWA³, J. OHMAN², K. M. HARTIKAINEN¹;
セッション名       ： Executive function
Abstract            ： Deep brain stimulation (DBS) of anterior thalamic nuclei (ANT) is a novel promising therapeutic method for treating refractory epilepsy with CE approval in Europe since 2010. Despite reports of subjective memory impairments and mood disturbances in patients with ANT-DBS, little is known of the effects on cognitive and affective processes. We assessed the effects of ANT-DBS on cognitive performance and emotional reactivity in 12 patients with ANT-DBS for intractable epilepsy.  Patients performed a computer based executive-reaction time (RT) test with threat-related emotional distractors. Executive RT-test is a visual Go-NoGo attention task requiring multiple cognitive control functions to be engaged simultaneously, e.g. inhibition of prepotent responses and emotional distraction, switching rules and working memory. In addition to assessing executive performance the test taps into emotional reactivity. The DBS stimulation was switched ON (180 Hz) and OFF every few minutes with patients blind to stimulator settings. For half of the experiment the active electrode was the one closest to the ANT in postoperative CT-MRI fusion images, while for the other half the most distant electrode from the ANT was selected as an active electrode (OA). Order of active electrode contact was balanced within the group. Repeated measures analysis of variance was conducted separately for RTs and different error types with Emotional value of the distractor (neutral, unpleasant), Stimulation (ON, OFF) and active electrode Location (ANT, OA) as factors. There was a significant interaction effect of Emotion and Stimulation (p=0.004) in RT analysis. Emotional distractors significantly slowed RTs when the active electrode was in ANT (p=0.044) and when the stimulator was on (p=0.002). Commission errors, reflecting failure in withholding from responding, showed significant main effect of Stimulation (p=0.030). Stimulating ANT increased the amount of commission errors (p=0.027). In conclusion we found immediate objective effects of ANT-DBS on human cognition and emotion. ANT-DBS impaired cognitive control and altered emotional reactivity. The results bear clinical relevance in highlighting the need to consider affective and cognitive side-effects along with the therapeutic effect when choosing the optimal stimulation parameters. The Executive RT-test might be used as a tool to objectively assess subtle alterations in affective and cognitive processes due to DBS. Also, this study introduces a novel window into affective processes by modulating the limbic system with direct stimulation of a key node in the thalamus.
この発表は，GO/NOGO taskを施行する際に，先行刺激に感情を発生させるような刺激を提示すると，注意がemotionalの処理に働き反応時間が遅くなるという研究発表でした．私の研究にもGO/NOGO taskを用いて課題刺激の違いを明らかにしようとしているので，非常に面白いと感じました．注意機能や反応抑制以外の課題要素が含まれれば含まれるほど反応時間が遅くなる可能性があり，私の研究でも今後注意力や反応時間を意図的にバラつかせる必要があるので，emotionalを課題設計に取り入れるか入れないかも検討したいと思います．
 

発表タイトル       ： Longer reaction time is associated with increased task-specific cognitive control and decreased default mode activity

著者                  ：*A. D. BARBER^1,2, B. S. CAFFO³, J. J. PEKAR^1,2, S. H. MOSTOFSKY^1,2;
セッション名       ： Executive function
Abstract            ： Within-subject, trial-to-trial fluctuations in reaction time (RT) may reflect fluctuations in attention, integration of information across regions that implement different aspects of the task, or state changes in global network efficiency. Previous studies have found that specific regions are influenced by RT independent of task demands, which may reflect the particular function of the region (e.g. response selection demand). The current study examined RT effects on brain activity in two Go/No-go tasks: a Simple task with an intuitive stimulus-response mapping (green=go, red=no-go) and a Repeat task, with an inconsistent stimulus-response mapping (color change=go, color repeat=no-go), which required working memory for task performance.
22 healthy adults were scanned for two blocks on each task. Image preprocessing and analysis occurred in SPM5. First-level general linear models included up to seven condition trial onset regressors (Post-Rest Go, Go, Go RT, No-go, Commission Error, Omission Error, and Anticipatory trials on which the RT<200 msec), which were convolved with the canonical HRF, temporal and dispersion derivatives. In addition, nuisance regressors (six motion parameters, mean white matter, mean cerebrospinal fluid, and mean whole brain time-courses) and a block regressor for each functional run were included. First-level contrasts of Go RT revealed those regions that increased or decreased activity linearly with RT for the Simple and Repeat Tasks separately. Second-level group effects were examined across subjects.
In the Simple Task, slower RT was associated with increased activation in visual (BA 19), inferior and superior temporal (BA 37/39/22), inferior and superior parietal (BA 7/40), and postcentral gyrus (BA 5/2). In the Repeat Task, activation increases with RT occurred within a right frontal region spanning dorso- and ventrolateral cortices (BA 9/44/45/46), anterior insula (BA 13), pre-supplementary motor area and anterior cingulate (BA 6/8/32) and bilateral parietal regions mainly confined to inferior and superior parietal cortex (BA 7/40) with greater extent into supramarginal and angular gyri on the right side. Examination of regions that showed decreased activity with slower RT revealed the medial prefrontal cortex (MPFC: BA 9/10/32) for both tasks.
RT modulated activity in a unique set of regions for the two tasks, reflecting task-specific cognitive/attention control. Increased recruitment of these regions may reflect greater deliberate control in slow RT trials. Decreased MPFC activation in slow RT trials may reflect default mode network suppression when control increased.
この発表はGO/NOGO taskの難易度を視覚刺激の色変化で設計しているものである．課題の難易度が高くなると前頭部の正中線付近の活動部位が下部になるそうだ．反応時間と脳活動の関係も検討していて，反応時間とデフォルトモード・ネットワークの関係を示唆しています．
なお，簡単な課題において，遅いRTは視覚野(BA19)，下側頭葉，上側頭葉(BA 37/39/22)，中心後回(BA 5/2)を活性化させた．繰り返し課題ではRTの増加とともに右前頭における背側と腹側部(BA 9/44/45/46),前島(BA 13)，前補足運動野と前帯状(BA 6/8/32)，右側の角度変化回や頭頂皮質 (BA 7/40)で活性化された．遅いRTで不活性となった領域は内側前頭前皮質(MPFC: BA 9/10/32)であった．
 

発表タイトル       ： Separating auditory and visual attention networks using eye tracking and fMRI

著者                  ：*R. M. BRAGA, R. FU, R. J. S. WISE, R. LEECH;
セッション名       ： Attentional networks
Abstract            ： The dorsal attention network (DAN) is frequently proposed to be active for top-down attention to all sensory inputs (e.g. vision, audition, touch). However, most of the evidence for the DAN comes from visual studies, and its involvement in auditory attention is inconclusive. Core DAN regions the superior parietal lobe and frontal eye fields have retinotopic organization and are known to be involved in controlling eye movement. We therefore investigated whether activation of the DAN during auditory attention could be due to inadvertent control of eye movement.
We used functional magnetic resonance imaging (fMRI) at 3T with eye tracking in 20 humans who were performing a simple spatial/non-spatial listening task. Subjects were cued to listen to one of two competing melodies and were required to detect a key/pitch change that occurred unpredictably within some of the 8s trials. The competing sounds were played dichotically and diotically, meaning that spatial information was available in a portion of the trials. Eye movements were tracked inside the scanner. Subjects were naïve to the experimental hypothesis and were not told to fixate during the listening trials so that natural viewing and listening conditions could be studied. We covaried the effects of eye movement from an fMRI analysis to probe whether the networks for ocular control are separable from auditory attention.
Our behavioural results show that eye movement control occurs inadvertently but systematically during attentive listening. Subjects fixated significantly more during listening compared to rest trials, regardless of the experimental condition. In addition, during spatial (diotic) trials, subjects’ gaze position was biased towards the visual space ipsilateral to the target sound. The fMRI results showed strong activations related to eye movement that overlapped with the DAN, allowing separation of networks for eye movement control and auditory attention.
Our results suggest that auditory attention elicits systematic eye movements under natural listening conditions. This finding can help explain the controversy regarding the supposedly amodal nature of the DAN. Although the DAN may be recruited during auditory top-down attention, its role may remain a visual one [[unable to display character: &#8211;]] to reduce and bias eye movements in order to facilitate auditory perception. This suggests that top-down attention to a given modality may require the modulation of sensory control networks subserving other modalities. These cross-network interactions between the sensory systems may explain why the DAN, a largely visual network, is frequently implicated in non-visual top-down attention.
この発表は背側注意ネットワーク（DAN）が視覚刺激を用いた実験が多いので，聴覚刺激で実験を行い本当に頭頂部や前頭眼野が注意制御に関連しているかどうかを検討した研究です．空間的/非空間的聴覚注意を用い，fMRIと視線追跡によって注意を計測していて，すごく人気を集めている発表でした．やはり課題によってネットワークが変わること，キーとなる領域が同じ，または異なることを証明する研究は大切なのだなあとモチベーションが上がりました．
 
 
 

発表タイトル       ： Common principles underlying visual, auditory and tactile working memory resources

著者                  ：*S. JOSEPH¹, S. KUMAR^2,3, P. IVERSON⁴, S. TEKI³, S. K. SCOTT*¹, T. D. GRIFFITHS^2,3, M. HUSAIN*^5,6;
セッション名       ： Working memory
Abstract            ： A prevalent view of working memory (WM) considers it to be capacity-limited, fixed to a set number of items. However, recent shared resource models of WM have challenged this ‘quantized’ account using measures of recall precision. Although this conceptual framework can account for several features of visual WM, it remains to be established whether it applies to other sensory modalities.
We tested whether the resource model can be extended to auditory and tactile WM. For the audition, recall precision was measured for pitch and speech sounds. With respect to touch, we measured precision for vibrotactile frequencies. Novel matching tasks were designed to probe participants’ memory for each stimulus feature. In each experiment, after the presentation of a sequence of stimuli, a probe stimulus appeared which had to be adjusted to match a selected target. This continuous, analog response method allowed us to measure recall precision for the respective stimulus feature. Crucially, this provides an index of the variability of a memory representation around its true value, rather than a binary “yes/no” recall measure typically used in change detection paradigms.
Our findings support key predictions made by the resource model: We show a monotonous decline in memory precision with an increase in memory load, suggesting no discrete item limit, for audition and touch. The results show that there is no fixed upper limit to the number of stimuli that can be stored in WM, a principle that obtains across sensory modalities. Instead, the resource model, previously shown to account for visual WM processes, can be extended to auditory and tactile WM. A unified mechanism – the resource model – provides a biologically plausible description for WM mechanisms across the senses.
この発表はワーキングメモリにおいて視覚的な実験が多く行われ，リソース・モデルも視覚的実験をもとに定義されているが，そのモデルを聴覚刺激や触覚刺激に対しても拡張できるかどうかを検討した研究でした．メモリや注意の容量やレベルを検討するならば，やはり課題の変化に対応して変化する指標を探さなければいけないと再認識しました．そしてやはり現在検討されているモデルなどは視覚刺激をもとにしたものが多く，その結果が課題に因るものではないかどうかが見直され始めていると感じました．
 
 

発表タイトル       ： Visual rhythm perception improves through multisensory (but not unisensory) training

著者                  ：*B. BARAKAT¹, A. R. SEITZ², L. SHAMS¹;
セッション名       ： Human learning: Perceptual and spatial learning
Abstract            ： Research has shown that multisensory training can facilitate unisensory perceptual learning (Seitz et al., 2006,Current Biology; Kim et al., 2008, PLoS ONE). This facilitation has been demonstrated in visual motion perception, but it is unclear whether this phenomenon generalizes to other types of perceptual learning. Furthermore, previous studies have shown that, compared to the auditory modality, the visual modality is significantly less proficient at discriminating the rhythms of temporal sequences. However, no previous study has examined whether rhythm discrimination in the visual modality is a trainable perceptual skill. In light of this, we examined whether multisensory training can facilitate participants’ ability to discriminate visual rhythmic sequences before, during, and after two days of perceptual training. Participants were trained with either visual-only or audio-visual stimuli. Specifically, participants performed a visual rhythm discrimination task in which they judged whether the rhythms of two consecutive visual sequences (as conveyed by a blinking white disc) were the same or different. During training, the audio-visual group was presented with pure tone beeps that were congruent with the onsets/offsets of the blinking white disc, whereas the visual-only group was presented with only the visual stimulus. During pre- and post-tests, both groups were tested with visual stimuli only. We find that visual rhythm discrimination is improved in the audio-visual training group, but not in the visual-only training group. Furthermore, the improvements in the audio-visual group were long-term (>24 hours between tests). Our results suggest that, in certain tasks, performance in one modality can not only be facilitated by engaging another modality during training, but it may be a necessary condition to produce learning when unisensory training alone is insufficient.
この発表は多感覚トレーニングが単一感覚学習を向上させると言われているが，その実験が視覚を用いたものであったため，聴覚でも再現されるかどうかを確認している研究でした．感覚によって学習による成績向上の傾向が違うかどうかは，今後私の研究にも関与する重要な問題です．多感覚刺激と単一刺激ではネットワークが異なると考えられますが，私たちが行っている非侵襲な実験で完全な単一刺激を用いることは難しいし，検討方法は気をつけなければいけないと感じました．

 
1. 講演会の詳細
2013/11/09から2013/11/13にかけて，San Diego Convention Centerにて開催されましたNeuroscience2013 1) に参加いたしました．このNeuroscience2013は，Society for Neuroscienceによって主催された研究会で，生体計測および脳機能イメージング装置を用いてNeuroscienceneにおける議論を行い，あらゆる生物学的組織における研究の促進や新たな科学的知識の応用により，治療方法の開発や脳神経学の理解を深めることを目的に開催されています．
私は8～13日の会期全てに参加いたしました．本研究室からは他に山本先生，木村，杉田，將積，井上，眞島，早川が参加しました．
 
2. 研究発表
2.1. 発表概要
私は13日の午後のセッション「Functional Mechanisms of Attention Ⅱ」に参加いたしました．発表の形式はポスター発表で，60分の講演時間となっておりました．
今回の発表は，心理状態が異なる色温度環境における注意の持続および脳血流変化に与える影響を検討したものです．発表タイトルは「Discussion of brain functional on the effects of
color temperature on sustained attention using functional near-infrared spectroscopy」
です．以下に抄録を記載致します．
 

[Purpose]We investigated the effect of color temperature on sustained attention from the point of view of brain function using functional near-infrared spectroscopy (fNIRS). This study aims to derive appropriate light environments for operating efficiency. This study describes that high color temperature improved the performance and the superiority of right hemisphere of the brain.[Methods]To investigate brain activity during sustained attention, subjects performed go/no-go task. Thirty-four healthy young men (age, 21.5 ± 0.5 years) participated in this study. We measured cerebral blood flow changes in the inferior frontal cortex (IFC) under sustained attention using fNIRS. During the go/no-go task, subjects were exposed to two different lights (high color temperature at 7966 ± 65 K and low color temperature at 3226 ± 28 K). We investigated the go/no-go task performance and hemispheric dominance during sustained attention. The performance was evaluated based on an error rate and reaction time (RT) of the go/no-go task. Reaction of the subject was counted as error when the reaction time of go trials was >500 ms. Laterality index (LI) was used to evaluate the hemispheric dominance of sustained attention. We investigated the hemispheric dominance using the median of the total hemoglobin change (L: left IFC, R: right IFC) during the go/no-go task.[Results]Approximately 68% subjects demonstrated fast reaction on high color temperature, whereas they exhibited significantly shorter RT on high color temperature (p < 0.05). LI analysis demonstrated that IFC activity was higher in the right hemisphere when exposed to high color temperature.  We suggest that high color temperature affects the right hemisphere superiority and improves performances.  When we considered error rates, we observed that the group of low error rate was significantly smaller at high color temperature (p < 0.05). These results suggest that the group of subjects with low error rates demonstrated a greater IFC activation when exposed to high color temperature than subjects with high error rates. [Conclusions] This study demonstrates that high color temperature affects the right IFC and is associated with improved cognitive performances. The results reveal that when exposed to high color temperature, almost all subjects performed fast responses.

 
2.2. 質疑応答
今回の講演発表では，以下のような質疑を受けました．
・fNIRSとはどのような装置なのか．
九州工業大学の水野雅晴先生から頂いた質問です．
生体を透過しやすい近赤外光を用いて脳の神経活動に伴い変化するOxy-HbとDeoxy-Hbの相対変化量を計測できる装置，と回答致しました．
 
・GO/NOGO Taskで音刺激以外を用いたものはあるのか．
　九州工業大学の水野雅晴先生から頂いた質問です．
ランプを点灯させる刺激や顔の表情を用いた視覚刺激，指に電気刺激を与える体性感覚刺激などが先行研究で用いられている，と回答しました．他の刺激を用いることにより，違った面白い結果が得られるのではないか，というアドバイスを頂きました．
 
・Blueライトが効果的な作業は他に何があるのか．また，Redライトが効果的な作業はあるのか．
早稲田大学大学院文学研究科の中島悠介さんから頂いた質問です．
Blueライトが適している作業は計算や短期集中で作業を行いたい時，Redライトが適している作業は読書や会議の時，と回答致しました．BlueやRed以外の色温度でも実験を行ったらよいのでは，というアドバイスを頂きました．
 
・fNIRS実験における被験者の負担は大きいのか．
早稲田大学大学院文学研究科の中島悠介さんから頂いた質問です．
fNIRSは非侵襲で，被験者は座位や運動など自由な体制で計測できるため，負担は少ないと考えられる，と回答致しました．
 
・被験者の群分けはどのように行ったのか．
早稲田大学大学院文学研究科の中島悠介さんから頂いた質問です．
実験開始前にPOMSのアンケートに回答してもらい，6つの尺度それぞれに対して被験者の平均得点と20代男子の年齢階級別得点と比較した．すると，「活気」の項目のみ正常値を逸脱していたので，「活気」の得点が正常値を「活気群」，それ以外を「不活気群」として群分けを行った，と回答致しました．
 
・Task Performanceに関して群間で有意な差が見られなかったのか．
Swartz Center for Computational Neuroscience, Institute for Neural Computation, University of California San Diegoの宮腰誠先生から頂いた質問です．
群内ではBlueとRedで有意な差が見られたが，群間では有意な差が見られなかった，と回答致しました．ブートストラップ法など色々な検定方法を検討したら有意な差が見られるかもしれない，とアドバイスを頂きました．
・BlueとRedで実験を行っているが，Greenの色温度で実験は行わないのか．
OHAIPAT CHUNHARASさんから頂いた質問です．
色度図を見て頂き，色温度で明確に緑色を表すようなものは存在しない，と回答致しました．
 
・POMSのアンケートはどのように回答するのか．
　　Yang YouPingさんから頂いた質問です．
提示された項目ごとに「まったくなかった (0 点)」から「非常に多くあった (4 点)」までの 5 段階 (0～4 点) のいずれか一つを選択する方式である，と回答致しました．
 
・GO/NOGO Taskとはどんなタスクか．
　京都大学大学院の杉本光さんから頂いた質問です．
GO信号とNOGO信号の二種類の刺激に対して，GO信号の時には素早く反応し，NOGO信号の時には反応しない課題である．脳機能的には，NOGO信号には反応しないという反応を抑制する機能働いている，と回答致しました．
 
2.3. 感想
初めての国際学会で緊張しましたが，多くの方と研究についてディスカッションすることができ，とてもよい経験になりました．聴講の際には積極的に質問をすることが出来ましたが，英語がなかなか伝わらなかったり，専門用語が理解できなかったりしてので，もっと英語の勉強を頑張らないといけないと思いました．つたない英語でも理解して頂けたは嬉しかったです．多方向の視点からの意見を頂き，とても貴重な経験をすることができました．英語の勉強と共に研究もより一層頑張りたいと思いました．
 
3. 聴講
今回の講演会では，下記の5件の発表を聴講しました．
 

発表タイトル      ：　Parahippocampal and retrosplenial cortex are more active during remembering than during episodic future thinking著者                  ： A. W. GILMORE, S. M. NELSON, K. B. MCDERMOTTセッション名       ： Human Cognition and BehaviorAbstruct            ：Recent neuroimaging studies have demonstrated that both remembering events from the past and imagining events in the future activate a common set of regions within the human brain’s default network (Schacter et al., 2012). While researchers have often found regions exhibiting greater activity for imagined future events relative to remembered past events (e.g., Szpunar et al, 2007), the reverse pattern (i.e., Remember > Imagine) has not been consistently observed. A number of hypotheses (Addis et al., 2007; Szpunar et al., 2007) suggest that this is due to the increased processing demands present during future simulation when combining details into a novel, coherent narrative. A reasonable alternative is that studies have simply failed to isolate regions showing greater activity for remembered past events. This subfield of cognitive neuroscience is still in its relative infancy, having come to the fore a little over half a decade ago, and thus the number of studies that have been conducted so far is relatively small. In this study we used functional magnetic resonance imaging (fMRI) to attempt to locate regions that show sensitivity to remembered past events by asking participants to remember events from their past, imagine events that might occur in their future, or imagine events involving a familiar other. Across 3 separate experiments we found regions in paraphippocampal and retrosplenial cortex that show greater activity when remembering past events than in other experimental conditions. By using both standard rapid event-related and catch trial fMRI designs (Ollinger et al., 2001), we found that this sensitivity persists when examining task trials as a whole, or when controlling for possible differences in trial-by-trial task orientation signals in the BOLD response. These regions have previously been implicated in mental simulation, and sit adjacent to, but outside of, the default network. They correspond to locations that are thought to be involved in processing contextual information (Bar, 2009). We hypothesize from these results that a signature of past experience is, at least in part, based on the amount of contextual information associated with a given event during episodic simulation.

この発表は，単純記憶よりも文脈に基づく記憶の時にPHCとRSCで強い応答が見られる，という報告でした．過去の経験に基づいて未来を予想する際と同じ部位での血流増加が確認された．
 

発表タイトル      ：Neural basis of object-based shifting of attention in working memory著者                  ：B. PETERS, B. RAHM, J. KAISER, C. BLEDOWSKI,セッション名       ：Human Cognition and BehaviorAbstruct            ： Working memory (WM) enables the retention of a limited number of items for a short period of time. In addition, many situations require that a subset of WM contents be transiently prioritized for processing by focusing attention on them. Current models of WM suggest that the same attentional mechanisms that are known from perception also operate in WM. In vision, shifts of attention between spatial positions within the boundaries of one object are performed faster than shifts between positions located on different objects. This within-object benefit can be explained by an automatic spread of attention within perceived object boundaries in visual cortex. Hypothesizing the same attentional mechanisms in WM as in perception, we tested whether the within-object benefit can be observed, both on the behavioral and neural level, when subjects focus attention on spatial positions that are no longer physically present but represented in WM. 20 healthy subjects were presented two objects each containing two highlighted spatial positions. They had to memorize all four spatial positions. Attentional shifts in WM were faster for spatial positions located on the same object compared with equidistant positions on separate objects. Shifting attention in WM thus showed a within-object benefit comparable to the effect observed in a perceptual version of the same task. This behavioral benefit was associated with increased BOLD activity in posterior parietal cortex that could not be explained by differences in eye movements between conditions. Moreover, analysis of retinotopic visual cortex revealed that the automatic spread of attention within object boundaries was present also for information held in WM. Specifically, when attention was shifted to a memorized position, activity in early visual areas was enhanced at the retinotopic location corresponding to the second position co-located on the same object compared to equidistant positions located on the other object. These results extend the previous suggestion of shared mechanisms of spatial attention in perception and WM by demonstrating that this notion also holds for object-based attention. Attentional selection of a memorized position leads to a neural co-activation of another memorized position within the same object. This suggests that when object-like representations are held in WM, attentional selection includes activation of the complete object, thus accounting for the within-object benefit.

この発表は，物体の空間認知におけるワーキングメモリの働きを調査したものでした．物体を移動させた後に，被験者の視野探索を行ったところ，物体が以前存在していたところに最も注意が向けられていたことが証明された．空間認知の際に，注意の変化がワーキングメモリにおける血流増加と後頭部における血流変化が関連していることが報告されています．
 

発表タイトル      ：　The song in your head: identifying tonal frequency patterns in auditory cortex著者                  ： J. M. THOMAS, I. FINE, G. M. BOYNTON,セッション名       ： Auditory SystemAbstruct            ： Purpose:Recent fMRI (Formisano et al. 2008) and EEG studies (Schaefer et al. 2011) have shown that it is possible to identify an auditory stimulus based on the spatial pattern of activity within human auditory cortex (AC). Here we describe a decoding method using the quantitative population receptive-field model (Dumoulin and Wandell 2008) to estimate what auditory stimulus was presented based on BOLD responses in AC (Kay et al. 2004). Using this model we were able to not only successfully classify novel stimuli, but also to accurately estimate the frequencies presented in the stimulus over time. For simple pure tone stimuli, it is possible to reconstruct a reasonable representation of a person’s auditory experience from measurements of brain activity. Methods: Data were collected from 4 subjects (age: 26‐ 45 years) on a 3T Philips Achieva using an 8-channel head coil. Pure tone stimuli were presented at an equal perceived volume (65-85 dB) as a random sequence of 240 unique frequency blocks (88-8000 Hz). Our pRF analysis assumes that the sensitivity of a voxel is a 1D Gaussian of log frequency and finds the centers and widths that best-predict the fMRI time-courses to the random stimulus. These pRFs were then used to estimate the frequencies presented over time from the time series generated by novel pure-tone sequences. This was done with a fitting algorithm that identified the series of frequencies for which the (previously estimated) pRFs generated a predicted time series that best matched the measured BOLD responses to the novel stimulus over time. Results: pRF centers were tonotopically arranged in mirror-symmetric gradients running perpendicular to Heschl’s gyrus, likely corresponding to hA1 and hR subdivisions of primary auditory cortex (PAC) (Da Costa et al. 2011, Humphries et al. 2010, Striem-Amit et al. 2011). Performance classifying different tone sequences was near perfect. When identifying individual tones over time, the correlation for individual TRs between the actual frequency presented and the predicted frequency was .7632. Averaging across all trials (subjects, scans, and TRs) the correlation was .9631. Tone identification errors were limited to tones similar in frequency likely due to the relatively broad pRF bandwidths of most voxels, evoking similar levels of activation for nearby tones. Conclusions: The pRF model can be used in auditory cortex to identify individual pure tones presented over time. A natural extension will be to apply these methods to more natural and behaviorally relevant stimuli, such as music (Schaefer et al. 2011) and speech (Formisano et al. 2008).

この発表は，pRFモデルは，経時変的に呈示され，個々の純音を識別するために聴覚野でしようすることが可能であり，音楽や音声などより自然な方法と行動の関連刺激を適用できることを報告したものです．
 

発表タイトル      ：　Memory for nonspatial context in parahippocampal cortex著者                  ： R. A. DIANA, R. W. STRONG, A. M. A. FEHRセッション名       ： Human Medial Temporal Lobe:NeurophysiologyAbstruct            ： Episodic memory is defined by the association between an event and its context. The context of an event is the collection of details that characterize the event’s placement in time and space as well as its associations with other events. Such context details may even include information in the background of an event that is ostensibly irrelevant to the task at hand (as discussed by Elward & Rugg). Parahippocampal cortex (PHc) is known to be preferentially active during scene perception and therefore has been implicated in processing of spatial context. Recent theories, however, propose that PHc may process other types of contextual information, including nonspatial details such as an individual’s cognitive state or “train of thought” at the time of encoding (e.g. Diana et al, 2012). Evidence for the role of PHc in general contextual encoding comes from source memory studies in which encoding questions are specifically manipulated as the context of an event. These studies have consistently demonstrated a correlation between PHc activation and successful context retrieval, both when encoding questions were designed to be spatial and nonspatial in nature (see Diana et al., 2007 for a review). However, Epstein & Ward (2010) have questioned whether these previous experiments provide clear evidence for nonspatial processing in PHc, pointing out that even those source manipulations that were not intended to be spatial in nature may have included contrasts of recollection that could be based on spatial distinctions (e.g., Ranganath et al., 2004). The current study was designed to investigate medial temporal lobe activation associated memory for context information that lacks spatial components. Participants studied a series of words using encoding questions that were intended to limit the relevance of spatial information in context retrieval (e.g., judging a word’s part of speech). fMRI images were collected during both encoding and retrieval of context information. Subsequent memory analyses revealed that trials with successful context encoding (i.e., correct recollection on a later test trial) produced more activation in left PHc than did trials with unsuccessful source encoding (i.e., the decision to “skip” the source memory judgment for lack of information during a later test trial.) Our finding suggests that encoding of nonspatial context information is reflected in PHc activation and converges with findings by Aminoff & Tarr. We will discuss the implications of this result for processing of episodic context including the contributions of other brain regions to construction of this context, as discussed by Burwell, et al.

この発表は，関連情報と無関連情報を呈示した際に，無関連情報であっても，脳内で文脈を構成するネットワークができている可能性を報告したものです．エピソード記憶の際に活性する部位とその周囲の領域に関して脳の活性が見られたことが報告されています．

発表タイトル      ：　The behavioral analysis of a Go/NoGo task in school-aged children study in the Buddhist integrated education program著者                  ： J N. PHIANCHANA, K. SAMPOON, S. CHAITHIRAYANON, N.KOTCHABHAKDI, N. CHUTABHAKDIKUL, V. SIRIPORNPANICHセッション名       ： Human Cognition and BehaviorAbstruct            ： Educational system plays a crucial role in learning process of human. It is necessary for the development of young generation of people. Buddhist integrated education program is an alternative educational program in Thailand, which encompasses a variety of traditions, beliefs, and morality integrated with lessons that impact on cognition. Previous studies indicated that various meditative techniques in Buddhism can affect attention, an important component of cognition. In this study, the authors chose a Go/NoGo task which is a test for assessing the ability of sustained attention, stimulus discrimination and response inhibition. The Go/NoGo task requires the preparation and behavioral responses to the certain targets (Go-condition) as well as the inhibition of prepared response to other visual stimuli (NoGo-condition). The aim of present study is to investigate influence of Buddhist integrated education program on attention and inhibitory control in school-aged children by using ERP with a Go/NoGo paradigm. Behavioral parameters included reaction time, accuracy and cue errors were measured. A total of 51 healthy Thai school-aged between 11-12 years old participated in this study. They were separated into 2 groups: Buddhist integrated education group (n=22, 6 males and 16 females) and control group (n=29, 16 males and 13 females). Participants in Buddhist integrated education group were the grade 6 students who have studied in the Buddhist integrated school for more than 5 years since grade 1 while control group were the grade 6 students who have studied in standard school since grade 1. We found that the accuracy rate of Buddhist integrated education group had higher in “Go” condition (94.69%) than the control group (83.97%) (p<0.05). Moreover, Buddhist integrated education group showed less cue errors to warning stimuli (1.20%) compared with controls (3.28%) (p <0.05). Although, the reaction time for “Go” and accuracy rate for “NoGo” were not significantly different between groups. As a result, students in the Buddhist integrated education program revealed a better performance than the control group in attention task which might be explained from long consideration to response stimulus. Further ERP analysis may be essential for a conclusion about the effect of Buddhist integrated education program on attention and inhibitory control in school-aged children.

この発表は，仏教徒統合プログラムに参加した若い世代に視覚刺激のGO/NOGO Taskを行った際の注意の保持および反応抑制に関して調査した報告です．教育過程における注意・抑制課題の訓練は必要不可欠である可能性が報告されています．
 
参考文献
1)    Neuroscience2013，http://www.sfn.org/annual-meeting/neuroscience-2013
 

 
1. 講演会の詳細
2013/11/8から2013/11/13にかけて，San Diegoにて開催されましたNeuroscience2013参加いたしました．この国際学会は約3万人のサイエンティストが集まるという世界でも大きな学会で，内容としては脳科学や健康，病気など幅広い分野の新しい研究が紹介されていました．
私は最終日の11/13日の午後から発表いたしました．本研究室からは他に山本先生，木村さん，杉田さん，早川さん，将積さん，大西さんが参加しました．
 
1.1. 発表概要
私は18日の午後のセッション「Working memory Ⅰ」に参加いたしました．発表の形式はポスター発表で，約4時間の間自分の発表の研究紹介や質問に答えておりました．
 
今回の発表のタイトルは「Analysis of working memory using the reading span test: Basic research of regional brain activity on brain cortex using functional near-infrared spectroscopy」で，以下に抄録を記載致します．

In this paper, The relationship between working memory capacity and cerebral blood flow change was evaluated using the results of a reading span test (RST), which is a language working memory task. Individual differences exist in working memory capacity.  Good methods for evaluating brain functions related to working memory are　unavailable, but it is difficult to understand the state of individual working memory.  In this study, the relation between working memory and cerebral functions was observed using functional near-infrared spectroscopy (fNIRS). The regions of interest in the brain were the dorsolateral prefrontal cortex (DLPFC) and the left inferior frontal gyrus (LIFG). It has been reported that DLPFC is responsible for continuing cautions, while LIFG manages language processing.  First , the functional relation between DLPFC, which has the function of continuous cautions, and RST was observed.  In this respect, cerebral blood flow change in subjects with lower scores was higher than that in subjects with higher scores. Second, subjects were classified into two groups, i.e., high score group and low score group, and features of the two groups were examined. In both groups, LIFG was activated with different active patterns. In LIFG, brain activity was constant for the high score group, while it declined for the low score group. Simultaneously, the brain activity in the DLPFC region for the low score group increased.

1.2. 質疑応答
今回の講演発表では，以下のような質疑を受けました．
 
・質問内容1
質問者の氏名を控え損ねてしまいましたが，中国のかたからの質問です．こちらの質問は脳機能を測定しているのになぜMRIをつかわないのかということでした．この質問に対する私の回答は，ＭＲＩのようにただ賦活部位のみを検討するだけではなく，fNIRSのように時系列データを用いることで，時間差によるネットワークや関連部位についても検討できるのではないかと考えたからです．
 
・質問内容2
質問者の氏名を控え損ねてしまいました．関西学院大学の方からの質問です．もともとは苧坂先生の研究室にいらっしゃったそうです．低成績者にみられる脳血流の時間差は言語処理が上手くできなかったから中央実行系がはたらいたのか？そうでなくて低成績者はもともと言語処理が上手くできにくいので後から血流の活性は見られるが最初から中央実行系は働いていたのではないか？私はそのような考え方はなかったので今後、検討していくと答えました．
 
1.3. 感想
発表は日本人の方とはデスカッションも細かいところまで行うことができたり，アドバイスも実践できそうな細かいところまで教えて頂いたのでよかったと思います．外個人のかたとはやはり，ポスターに書いてあることを説明したうえで軽い質問にしか答えることができませんでした．その理由として考えられるのは，私の英語の説明が上手く伝わっておらずあまり質問をいただくことができなったことがあげられます．しかし，研究の内容に関してはとても面白いとたくさんの方に言って頂き、またマスター１年ということに驚きとお褒めの言葉をたくさんいただいたのが嬉しかったです．全体の感想としては本当に楽しくて4時間もあっという間でした．やはり英語は伝えようとすれば伝わる気はしますが，もっと奥深くまでデスカッションをしたなと思ったので英語能力を鍛えようと思います．
 
 
2. 聴講
今回の講演会では，下記の5件の発表を聴講しました．
 

発表タイトル       ：　Individual differences of cognitive ability differentiates neural 　and behavioral strategy during concurrent working memory and oculomotor task著者                  ： G. KWONセッション名       ： .Individual Differences: Cognition.Abstruct            ： Previously, we have shown that individuals with high K-CVLT (Korean Version of California-Verbal Learning Test) score recalled more words than individuals with low K-CVLT score under specific eye movement (EM), i.e. periodic smooth pursuit eye movement (SPEM). As the periodic SPEM is highly relied upon the cerebellar network, we hypothesized individuals with high innate cognitive abilities may better allocate their cognitive resources during periodic SPEM and therefore decrease the load to the fronto-parietal neural network. To investigate this hypothesis, we designed EEG and NIRS (near-infrared spectroscopy) neural imaging experiments. Our particular interest is to study neural correlates of individual differences in their network resource allocation strategy. During concurrent working memory and EM tasks, we collected EEG data using 32 channel EEG acquisition system (Biosemi, Netherlands) and hemodynamic changes by using 12 channel NIRS system (Korea University, Korea). The tests were done in group of college students (Sungkyunkwan University). From EEG and NIRS data, we found different electrical and hemodynamic activation patterns in the frontal areas between high and low working memory capacity group differentiated by K-CVLT score. Our data suggests that individual differences may drive different neural activation pattern, particularly in cortico-cerebellar tract which connects the frontal lobe and cerebellum. This study, combined with behavioral performance, may help us better understand the mechanism of neural network allocation during dual task.

この発表はK- CVLTというワーキングメモリ容量を測定する課題を用いて，そのスコアによって低成績と高成績のワーキングメモリ容量群との間で，前頭領域において異なる電気的および血行動態活性化パターンを見つけている．個人差が特に前頭葉および小脳を接続する小脳皮質管において、異なる神経活動パターンがあることを示唆していた．同じワーキングメモリ課題でDLPFCにおける結果が私と同じ結果であったことで印象に残りました．

発表タイトル       ：Disrupting human prefrontal cortex prevents performance gains from sensory-motor training著者                  ： H. L. FILMERセッション名       ： Cognitive Enhancing Effects of Exercise and PracticeAbstruct            ： Humans show large and reliable performance costs when required to make more than one simple decision simultaneously. Such multitasking costs are thought to reflect capacity limits in response selection (RS), the information processing stage where sensory input is mapped to an appropriate motor response. Neuroimaging has implicated the left posterior lateral prefrontal cortex (pLPFC) as a key neural substrate of RS. For example, activity in left pLPFC tracks improvements in RS efficiency typically observed following training. To date, however, there has been no causal evidence for the involvement of pLPFC in RS or training effects, and the left hemisphere lateralisation of this operation remains controversial. Here we employed excitatory, inhibitory and sham transcranial direct current stimulation (tDCS) and measured participants’ performance on high and low RS-load tasks after different amounts of practice. Both excitatory and inhibitory stimulation of the left pLPFC disrupted training effects for the high load condition relative to sham. No disruption was found for the low load and right pLPFC stimulation conditions. The findings support a causal role for the left pLPFC in both RS and training effects. It also suggests training improves RS efficiency by sharpening the neural ensemble in prefrontal cortex that performs sensory-motor translations.

同時に複数の単純な決定を行うため信頼性の高い性能を示している。このようなマルチタスクコストが応答選択における容量限界（RS），感覚入力が適切な運動応答に反映すると考えられている.
RSの重要な神経基盤として、左後側方前頭前野（pLPFC）が関与しているが因果関係は証明されていなかった．偽経頭蓋直流電流刺激（TDC）を用いて，ハイとローのRS-負荷の作業で測定参加者のパフォーマンスを測定した結果，RSとトレーニング効果の両方で左pLPFCための因果的役割を示唆した．LPFCを左右で測定していたが，左のみに差異が現れていたが，なぜ左だけに現れるのか不思議である．質問したが答えはよくわからなかった．
 

発表タイトル       ：Development and assessment of a cognitive training program based on problem solving in order to improve capabilities著者                  ： M.-H. FERRERセッション名       ： Cognitive Enhancing Effectsof Exercise and PracticeAbstruct            ：Cognitive or physical disabilities induced by illness or trauma can change a life. Indeed, patients have to deal with a double challenge: coping with deficits-induced novelty and successfully adapt. In this context, head trauma which result in major memory, attention and executive deficits, as well as in adaptive difficulties are of particular interest since they affect the ability to cope, rehabilitation and quality of life of patients. Here, we performed two studies. The first one aimed at identifying the cognitive processes on which to rely to promote adaptation. The second one aimed at developing a training program based on these processes and at assessing its effectiveness. In the first study, participants (n=137) completed subjective scales in order to assess their coping strategies and quality of life. Some cognitive components involved in problem solving were also tested. Our data show that when a person is efficient and fast to solve problems, it is also more resilient and uses functional coping strategies more easily when compared to others. We also showed that this kind of persons has a better quality of life. Among processes tested in problem solving and involved in adaptation, the particularly important ones are hypothetical and deductive reasoning, divergent thinking, mental rotation, identification embedded forms and ability to change viewpoint. Based on these results, we performed a second study, in which participants (n=30) took part to a 15-session cognitive training. Subjects were divided into a trained group (n=19) which performed the developed problem solving training program including closed problems (insight, hypothetical-deductive), open problems (divergent thinking) and pure visuo-spatial problems (Tangrams); and a control group (n=11) which performed cognitive activities consisting of arrow words and crosswords. Effects of training and cognitive activities were assessed by comparing neuropsychological data from pre and post-training evaluations. We also performed functional magnetic resonance imaging during resting state at pre and post-training times (data currently analyzed). Our hypothesis is that our training program may have induced modifications in brain connectivity at rest, which could be seen as a neurofunctional substrate of cognitive and psychological modifications induced by our training program. Preliminary cognitive data show that training problem solving abilities improves self-evaluation of problem solving capabilities as well as real performances. We also observed an improvement of visuo-spatial performances.

ワーキングメモリのトレーニングプログラムの開発とその有効性の効果を検討し，認知訓練を行ったワーキングメモリのトレーニング後の結果を示していた．トレーニング後の方が活性は大きくなることが示唆されている．また，今回は視空間課題を用いてたことから空間認知力も向上していることが示されていた．

発表タイトル       ：Brain activation patterns during semantic verbal fluency in active and educated healthy seniors: A covert fMRI study著者                  ： C. RODRIGUEZ-ARANDAセッション名       ： Human Cognition : Cognitive Aging ⅠAbstruct            ：Background. Word finding difficulties are usually reported among cognitively disease-free elderly. However, these language declines are not seen among highly educated seniors. The purpose of the study was to measure brain activity during mental retrieval of words in active, educated healthy elderly. We employed a semantic verbal fluency task (SVFT) for evaluation of word finding in an fMRI covert paradigm. A young group was recruited for cross-sectional comparisons. Methods. 15 younger adults (M = 26.8 years) and 17 healthy, highly active (leisurely and physically) elderly individuals (M = 70.6 years) participated in the study. Previous to fMRI scanning cognitive functioning was established for all subjects including performance on standard SVFT. To depict the neural substrates of word finding in SVFT we used BOLD fMRI at 1.5 T. We presented 6 categories in the semantic condition alternating with two baseline conditions: finger movements and passive resting condition. Each of the three conditions had a duration of 24 sec and was repeated six times in an alternating fashion. Subjects were instructed to mentally produce words related to each category, move their fingers following a trigger stimulus or do nothing during the rest condition. Results. Behavioral results showed that elderly performed cognitively similar to younger adults in most of the tasks including VFTs. For the fMRI results brain activity during SVFT was related to frontal and temporal regions in both groups. Though, activation was lateralized to left hemisphere for the young and more bilateral for the elderly. Elderly showed significantly higher activation than younger adults during SVFT as compared to resting condition on the somatosensory cortex, superior parietal, inferior temporal and cerebellum. Also, when SVFT was compared to the motor task older adults showed higher activation than younger subjects in frontal motor areas, somatosensory cortex, inferior temporal and various cerebellar regions. Conclusion. In spite of optimal cognitive function and no word finding difficulties, elderly displayed different brain activation from that of younger adults during performance of covert SVFT. Of interest is the increased activation in motor areas and especially in the cerebellum, which has been attributed a role in motor programming of speech generation. We conclude that the multifocal brain circuitry observed in highly active and well educated elderly is a compensatory mechanism for physiological changes in aging. Further research should focus on the possible compensatory role of cerebellar activity in language tasks among high-performing seniors.

通常は高齢者で認知機能に作業を及ぼすと言われている．しかし，高学歴の高齢者はそのような結果は見られないからそのような高齢者の脳活動を測定していた．行動の結果は若年層あまり違いはなかったが，脳機能には違いがみられた．高齢者の方が，体性感覚野や小脳などで大きな活性がみられた．音声生成におけるモータの役割にかかわっているのが，小脳と考えられている．
言語タスクにおける小脳の活動を調べる必要があるそうで，言語は前頭野やブローカやウェルニッケ野に関わっているだけだとおもっていたので，小脳の働きは意外でした．
 
 

発表タイトル       ：Activation related to training process for recognizing the noise-vocoded speech sounds: An fMRI study著者                  ： S. MURAIセッション名       ： Auditory System : Cortical Processing and Human Studies of Natural SoundAbstruct            ： Amplitude envelope information has been reported to be important for speech perception. The noise-vocoded speech sounds (NVS) are used as sound stimuli to reveal amplitude envelope-based speech recognition because frequency-specific cues are greatly reduced. NVS is synthesized from original speech by replacing original speech signal with noise bands with preserving their temporal amplitude envelopes. In this study, we focused on a process for learning NVS to investigate perceptual learning for spectrally degraded speech. For several days, we presented NVS and original speech with participants and measured brain activities. The original speech was a sentence consisted of 13-16 morae Japanese sentence (2-3 s) which was recorded at 16 bits and 8 kHz sampling rate and reduced noise below 60 Hz using high-pass filter. NVS was created by dividing the original speech into 3 bands (60-600, 600-1500, 1500-4000 Hz). The amplitude envelope from each band was extracted by half-wave rectification and low-pass filtering at 16 Hz. In addition, the amplitude envelope in each frequency band was multiplied with a band noise in the same bandwidth. This process made a speech signal severely distorted spectrally and unintelligible. The experiment was composed of training and test sessions. In training sessions, after participants perceived NVS sentence several times, they read the sentence in written text while listening to NVS sentence for them to confirm that auditory and visual stimuli were the same sentences. They were also presented a noise burst as a control condition. Their brain activities corresponding to perception of NVS, the original speech and the noise burst were recorded as whole brain echo-planar imaging data by functional Magnetic Resonance Imaging (fMRI) with the sparse temporal imaging technique, in which scanning was periodically sampled to avoid acoustic and electromagnetic interference generated scans. In test sessions, comprehension of NVS was objectively evaluated before the first training session and after each training session. Participants listened to NVS and reported how they perceived NVS without a feedback in soundproof chamber. Data showed that NVS could be greatly ｓintelligible for participants after several sessions of training regardless of severe spectral degradation. We observed patterns of activation changed in several brain regions through training. Our findings suggest that cortical neural networks develop to make NVS intelligible.

力丸先生ところの研究室のかたの発表を聞いてきました．劣化雑音を聞かせて訓練することにより，劣化雑音から音声が認識できるようになる時の脳活動の変化を研究していらっしゃいました．
言語音声を認識するのはウェルニッケ領域部位なのかと思うと，ウェルニッケの活性はあまり見られずブローカのみの活性でした．私は音声情報を理解するウェルニッケ野の方が，上位機能だと考えていました．音声を理解するまでもなくブローカ領域のみで活性が得られていたので，また検討する必要があるなと思いました．
 
 
参考文献
1)    NeuroScience2013, http://www.sfn.org/annual-meeting/neuroscience-2013
 

 
1. 講演会の詳細
2013年11月9日から　13日にかけてサンディエゴコンベンションセンターにて開催されました，Neuroscience2013に参加致しました．この学会は，神経科学分野で最大とされている学会であり，最新の神経科学分野の情報を得られる場とされている．近年，機能的磁気共鳴画像(fMRI)や脳磁図(MEG)などを用い，脳機能を理解する試みを促進することを目的に開催されています．本研究室からは他に山本先生，木村，杉田，井上，大西，真島，早川が参加しました．
 
2. 研究発表
2.1. 発表概要
私は11/12の午前のセッション”Perception: Auditory, Tactile, and Multisensory”に参加致しました．発表の形式はポスター発表で，4時間のうち，決められた1時間は必ずポスターの前に立って来た人に説明するというものでした．
今回の発表は，”Gender Differences in Influence of Sound Environments on Performance of the Memorizing Numerical String Task and Cerebral Blood Flow Changes”というタイトルで行いました．以下に抄録を記載致します．

[Purpose]In the former studies, it was demonstrated that sound environments affect the results of intellectual work and cerebral blood flow changes using functional near-infrared spectroscopy (fNIRS), i.Furthermore, psychology studies have reported that gender-specificity exists in the influence of pleasant and unpleasant sounds on the work environment. In this study, we investigated gender difference in the influence of sound environments by scoring a memorizing numerical string task and observing cerebral blood flow changes.[Methods] This study examined 24 subjects, among which 12 were males and 12 females. In this study, we selected three sound environments, namely, silence; “the sonata for two pianos in D major, K.448” by Mozart; and white noise. Subjects were exposed to sounds while working. The effect on intellectual work was analyzed by measuring the number of correct answers to 30 questions.　 Subjects had to memorize eight numbers in 3 sec and input them in the correct order in <7 sec. We examined the influence of different sound environments on the task by measuring cerebral blood flow changes using fNIRS. [Results] The results revealed that males showed the best performance when exposed to silence, whereas females showed the best performance in the presence of white noise. The influence of sound environments on the score was significant at 5% level in both males and females as calculated using the two-way factorial ANOVA without replications. Simultaneously, the results of the t-test at 5% level showed significant differences between males and females only in the presence of white noise. In addition, the same significant difference was observed in the average cerebral blood flow change. Cerebral blood flow change in males decreased and that in females increased. Moreover, it was observed that cerebral blood flow change decreases under pleasant sound conditions and increases under unpleasant conditions. Also in this experiment, in the white noise, cerebral blood flow change in males was tended to decrease and that in females tended to increase.　Therefore, we suggest that males may feel that the white noise is unpleasant as opposed to females. In conclusion, females showed the best performance in the presence of white noise, under which their cerebral blood flow change increased. Based on these results, we found that there is a gender-specific difference in the performances of intellectual work and cerebral blood flow changes in the presence of white noise.

 
2.2. 質疑応答
今回の講演発表では，以下のような質疑を受けました．
・質問内容1
こちらの質問は，ホワイトノイズは女性にとって本当に良いものなのか，というものでした．聞いてくださったほとんどの方にこの質問を頂きました．ホワイトノイズは男性にとって不快，女性にとって快であるという参考文献がある．実際に，アンケート調査も行ったが，被験者の心理状態にもそのような傾向が見られた，という内容で答えました．明治大学，認知脳科学研究室所属の土田江一郎さんには，「女性と男性の声の周波数帯域が異なり，ノイズの周波数帯域と似ているとしたら，普段よく聞いている声の周波数帯域などの要因も影響してくるのではないか」 というアドバイスを頂きました．
 
・質問内容2
明治大学，認知脳科学研究室所属の大橋洋平さん，何名か外国人の方から頂いた質問です．こちらの質問は，ピンクノイズとホワイトノイズはどのように違うのか，というものでした．ピンクノイズは音のパワースペクトルが周波数に反比例する音で，ホワイトノイズはパワースペクトルが全ての周波数に対して等しい音である，と答えました．実際に音も聞いていただきましたが，違いはほとんど分からない，という感想を頂きました．
 
・質問内容3
同志社大学，知覚・認知脳神経機構研究室所属の村井さん，外国人の方から頂いた質問です．こちらの質問は他の部位の脳血流変化はどうなっているのかというものでした．今回左側頭部の脳血流変化を用いて検討したのは，検定，積分値により活性部位を抽出した結果によるものであること，また，この左側頭部の下前頭回付近は，記憶や認知を司るとされていることを説明しました．
 
・質問内容4
同志社大学の村井さんから頂いた質問です．こちらの質問は各被験者によって活性量は大幅に異なるものなのか，というものでした．被験者内では全ての計測部位において，活性の幅は同程度である．しかし，被験者間では光路長が異なり，活性量も大きく異なる傾向がある．被験者間で比較するためには，正規化などの処理をしなければならない，という内容で答えました．
 
・質問内容5
京都大学，人間・科学研究科所属の宣本花凜さんから頂いた質問です．左側頭部が活性していたのはなぜなのか，というものでした．数字記憶課題が数字を記憶するものであること，入力するという動作を含むこと，数字を唱えて記憶したため言語領域と関係したことが考えられ，左側頭部の下前頭回付近が活性したと考察した，と答えました．このことについて，下前頭回には注意や制御の機能があるため，音を聞かないように注意や制御して活性した可能性もある，というアドバイスを頂きました．
 
2.3. 感想

私の発表は朝のセッション，また，会場の隅の方だったこともあり，まず通る人がほとんどいませんでした．前回発表した学会では，話しかけることがあまりできなかったことが反省点でしたが，今回は自分から話しかけることで，聞いて頂き，質問やアドバイスを頂くことができました．全ての方に分かったと言って頂くことができ，また，受けた質問にもきちんと英語で答えることができて良かったです．やはり，男性としては女性がホワイトノイズで成績が良くなるのは理解できない，という感想が多かったのですが，多くの方におもしろい結果だと言って頂くことができたので良かったです．一方で，被験者数がまだまだ足りないなと実感し，また，音の周波数解析など課題はたくさん見つかりました．

3. 聴講
今回の講演会では，下記の5件の発表を聴講しました．

発表タイトル       ：　Combined cognitive and physical training vs. single cognitive training in healthy eldery: Differences in long-term effects

著者                  ： J. Rahe
セッション名       ： Human Cognition: Cognitive Aging I
Abstract            ： Only a few studies report stronger cognitive effects of combined cognitive and physical training (CPT) compared to single cognitive training (CT) in healthy elderly and even less have examined long-term effects of cognitive interventions.
Methods: Healthy elderly (N=42) were trained with a CPT named NEUROvitalis Plus or a CT named NEUROvitalis. Both trainings were conducted in a period of six weeks with two 90-minutes-sessions per week. Neuropsychological performance was assessed directly before and after the training as well as one (FU1) and two (FU2) years after the posttest. Eleven subjects of each group completed all requirements.
Results: From pre- to posttest, both groups showed significant improvements in short- [CT (p≤0.00); CPT (p≤0.00)] and intermediate-term memory [CT (p≤0.05); CPT (p≤0.01)]. Additionally, the CPT group improved in verbal fluency (p≤0.00), the CT group in attention (p≤0.01) and processing-speed (p≤0.05). At posttest, both groups showed significantly better performance in intermediate-term memory [CT (p≤0.00); CPT (p≤0.01)] and attention [CT (p≤0.01); CPT (p≤0.05)]. At FU1, the CT group also showed improved verbal fluency (p≤0.05). The effects on verbal fluency could be preserved until FU2 in both groups [CT (p≤0.01); CPT (p≤0.05)]. The short- (p≤0.00) and intermediate-term memory (p≤0.01) could be stabilized at FU2 only in the CT group, but non-significant tendencies are recognizable in the CPT group as well.
Discussion: Significant pre-post effects in cognitive performance were found in either training. The participants of CPT did not outperform the CT group in the cognitive assessments. At follow-ups, in both groups some of the effects could be preserved, but there were differences concerning the stabilized domains in CPT and CT. In the future, CT and CPT for healthy elderly should be compared in larger sample sizes and researchers should investigate which cognitive domains could be improved by different training forms.
認知課題のトレーニングを行う際，課題によっては認知トレーニングだけでなく，身体的トレーニングと認知トレーニングを組み合わせた方がパフォーマンスが向上する，というものでした．注意課題は，柔軟運動と組み合わせた時にパフォーマンスが良くなる傾向がありました．私が用いている数字記憶課題のような短期記憶では，そのような傾向は見られないそうで，残念でした．
 

発表タイトル       ： Variations in working memory capacity: Suppression of distractors or enhancement of the targets?

著者                  ： R. Gulbinaite
セッション名       ： Individual Differences: Cognition
Abstract            ：　Visual-spatial attention allows filtering out distracting information and selectively processing only what is important. The ability to filter out irrelevant information has been suggested to be the primary factor determining an individual’s working memory capacity (WMC), a measure that strongly correlates with cognitive abilities, including intelligence. However, although WMC is predicted by filtering efficiency, it is unclear whether superior filtering abilities result from better suppression of the irrelevant information, enhancement of the relevant information, or both. Here we used the steady-state visual evoked potential (SSVEP) technique to dissociate processing of distractors and targets in the Eriksen flankers task, by tagging targets and distractors with different frequencies. We show that while preparing for the upcoming stimulus, high-WMC individuals suppressed distractors stronger than low-WMC individuals, whereas low-WMC individuals enhanced targets more than high-WMC individuals. These strategic differences between high- and low-WMC participants appear to reflect stable trait-like mechanisms, because they were not significantly predictive of trial-to-trial fluctuations in reaction times. In contrast, single trial behavioral performance was better predicted by attention to the targets. This finding suggests that whereas filtering abilities are important for WMC, it does not necessarily generalize to other tasks that put high demands on attentional control.
ワーキングメモリの容量に関する研究で，高成績であれば容量が大きく，低成績であれば容量が小さいとして，それぞれの活性を比較した研究でした．成績によって活性部位は異なり，また，刺激（課題）の強さによっても傾向が異なる，というものでした．私は，活性部位を決めてから，その部位で群によって活性を比較していたため，群分けしてから活性部位を比較してみようと思いました．
 

発表タイトル       ：Multidimensional affective ratings inventory (MARI): Standardized non-verbal, human vocalizations of emotion

著者                  ： M. D. Mullane
セッション名       ： Social Cognition: Behavior and Pharmacology
Abstract            ：　Emotional content in the world guides our behavior, influencing memory, decision-making, and learning. The scientific literature demonstrates the impact of visual emotional information on cognition, however the question of the influence of emotional information in the auditory world has remained largely unexplored. In order to investigate the effect of auditory emotional information on human cognition and behavior, we developed an inventory of 651 spontaneous, non-verbal vocalizations of emotion. These emotional human sounds were extracted from YouTube videos and recordings of actors simulating dramatic events, standardized for their length and amplitude and then rated by human subjects on 3 parameters: emotional valence, level of arousal, and dominance or autonomy.
Subjects rated the sounds based on the perceived impact the vocalizations had on them by selecting from among 9 figures on each of these 3 scales. The result is the Multidimensional Affective Ratings Inventory (MARI), a standardized inventory of human emotional vocalizations for use as an experimental instrument to examine the influence that auditory perception of non-verbal human vocalizations of emotion have on neural processes underlying cognition and behavior.
男性，女性の声を聴いた時に，男性，女性はどのように感じるのか，という研究でした．男性の声に対して感じる快の度合い，女性の声に対する快の度合い，どちらにも男女差が見られた，という結果でした．私の発表の際にもアドバイスを頂いたように，それは声の周波数帯域などが関係した結果かもしれない，と感じました．また，被験者数が651人ということで，やはり被験者数が多い方が説得力があるように感じました．
 

発表タイトル       ： Syntactic priming effect during second language sentence production by Japanese learners of English: An fMRI study

著者                  ： E. Nakagawa
セッション名       ： Language III
Abstract            ：　Syntactic priming is the tendency to repeatedly use the same syntactic structures across sentences (Bock, 1986). Previous behavioral studies on Japanese learners of English as a foreign language (EFL) have shown that syntactic priming rate depends on the learners’ proficiency (Morishita, 2011). This implies different mechanisms of syntactic priming for learners of different proficiency. However, it was unknown whether the neuronal activity would show a proficiency dependency.
The present study measured the extent of fMRI adaptation to repetition of uttering ditransitive sentences in a second language (L2). Twenty-five Japanese EFL learners participated in the study. They were asked to describe a series of pictures by completing the sentence fragment presented above them (e.g., The man gives⋯ ). We used pictures which could be described by using the following four verbs; give, hand, sell, and show. Two objects in the pictures were colored in green and red. These colors controlled the participants’ utterances and made them produce either a prepositional object (PO) construction, or a double object (DO) construction, by naming the green object before the red object (stoplight paradigm: Menenti et al., 2011). The same color-coded pictures also served as fillers when the fragment of the sentence above the pictures was in an ungrammatical order (e.g., gives The man⋯ ). In such case, participants were required only to name the two objects by referring to the green one first, and not to form a syntactic structure.
Within the areas showing the main effect of syntax (the effect of PO and DO trials versus filler trials) syntactic priming effect was observed in the lateral occipital (LO) areas and superior parietal lobule (SPL), and the left middle temporal gyrus (MTG), supplementary motor area, ventral premotor cortex extending to the inferior frontal gyrus (IFG). While a previous study on L2 have found syntactic priming effects in the left IFG, MTG, and precentral gyrus (Weber and Indefrey, 2009), we found syntactic priming effect in the LO and SPL. We assume that this reflects the fixation of the relationship between objects, which is prerequisite for syntactic processing, and the attention for L2 processing.
The present study has shown repetition suppression effect among Japanese EFL learners, when producing syntactic structures repeatedly. This result indicates that Japanese EFL learners are syntactically primed by their own speech, which implies the effectiveness of repetitive practice when learning L2 syntax.
文の構造が異なる言語を学習しようとする，統語的プライミングに関する研究でした．英語が得意な日本人，不得意な日本人とで，英語を話す際の活性部位が異なるそうです．やはり，様々な課題において，得意な被験者と不得意な被験者の活性部位は異なるものなのだと感じました．自身の結果についても，活性部位の考え方を考え直したいと改めて思いました．

発表タイトル       ： Imaging speech comprehension in quiet with high density diffuse optical tomography

著者                  ： M. Hassanpour
セッション名       ： Language IV
Abstract            ：　Although numerous studies have studied the neural basis of speech processing using fMRI, these studies all face challenges of acoustic contamination and/or relatively poor temporal resolution due to the constraints of echoplanar imaging. Here we measured brain activity in human listeners using high-density diffuse optical tomography (HD-DOT), an optical imaging method that permits presenting speech in a quiet acoustic environment and with excellent temporal resolution relative to the hemodynamic response. We presented listeners with spoken sentences that contained either a subject-relative or object-relative center embedded clause in order to identify networks supporting increased processing demands for syntactically complex sentences (i.e. object-relative clause), along with a control condition consisting of speech-shaped noise. Behavioral accuracy was high (mean = 97 % correct) across all conditions. Both the noise and the sentences activated regions of bilateral temporal cortex. In addition, the simple sentences activated the core language processing areas on the left hemisphere along left temporal and inferior frontal cortex. Finally, the increased processing demand for the syntactically complex sentences resulted in significantly increased activation in lateral temporal and frontal cortex. These results are in agreement with the previous fMRI studies and indicate the feasibility of imaging higher order cognitive processes with HD-DOT. These findings also indicate that HD-DOT is capable of detecting subtle changes in the networks recruited during processing of more demanding language tasks.
HD-DOT（拡散光トモグラフィ）という装置を使用し，言語の理解度を測る際の脳機能を調査した研究でした．課題の難易度も成績に影響してくるようで，被験者が課題に感じる難易度の調査も大事な検討項目だと感じました．
 
参考文献
1)    Neuroscience2013　ホームページ
http://www.sfn.org/annual-meeting/neuroscience-2013/abstracts-and-sessions
 

 
1. 講演会の詳細
2013/11/09から2013/11/13にかけて，サンディエゴにて開催されましたNeuroscience2013^１）に参加いたしました．この学会は，SOCIETY for NEUROSCIENCEによって主催された研究会で脳機能に関して情報共有することを目的に開催されています．
私は全日参加いたしました．本研究室からは他に山本先生，木村，将積，井上，真島，大西，早川が参加しました．
・その講演会が，どういう主旨，研究領域の研究会なのかについて説明
・講演会のWebサイトがあるなら，講演会名の点で参照する
・自分の参加日程と，他の参加者について説明
 
2. 研究発表
2.1. 発表概要
私は13日の午前のセッション「Mechanisms of Attention」に参加いたしました．発表の形式はポスター発表で，3時間ポスター前に立っていて，見にこられた方に説明するという流れでした．
今回の発表は，「Effect on brain function in inhibitory control during go/no-go tasks caused by changes in difficulty」という題目で行いました．以下に抄録を記載致します．

[Purpose]In recent years, brain functions have been observed using functional brain imaging techniques. However, effects of changes in the task parameters are hardly detected. In this study, we investigated cerebral blood flow (CBF) under task difficulty changes. The aim of this study is to investigate the influence of varying task difficulty, via manipulation of sound frequency within the auditory go/no-go tasks, on measured inhibitory response.[Methods] We used functional near-infrared spectroscopy (fNIRS) on both sides oflateral and prefrontal cortex to observe brain function activities. Thirteen adults completed the auditory go/no-go tasks. The tasks had a go signal at 1000 Hz and no-go signals at 1020, 1030, 1040, 1050, 1060 or 1100 Hz. [Results] According to the results, the reaction time and error rate tended to increase with decreasing difference in frequency between the go and no-go signals. It is suggested that the difficulty of the test depends on the frequency difference between the go and no-go signals. Thirteen subjects were given auditory go/no-go tasks with different difficulty conditions, namely high, medium, low, with a go signal at 1000 Hz and no-go signals at 1020, 1060, or 1100 Hz. Subsequently, CBF changes were measured using fNIRS. It has been reported that when CBF becomes active in a certain area, oxygenated hemoglobin increases near the area. Our results revealed that CBF of the right inferior frontal gyrus, whose function is to process inhibitory responses, was most active under medium difficulty. CBF of transverse temporal gyrus, whose function is to process sounds, was active under low and medium difficulties at the same level. In contrast, the CBF activation level was lowest under highest difficulty. Moreover, according to the results of the questionnaire survey on subjective difficulty, seven subjects of the thirteenth could not properly differentiate between go and no-go signals under high difficulty. We concluded that CBF of inhibition responses depends on task difficulty in the go/no-go tasks. We observed that when the subject could differentiate between go and no-go signals, CBF response was more active on the right inferior frontal gyrus, and this activation was correlated with the difficulty. However, when the subject could not differentiate between go and the no-go signals, the activation was smaller.

 
・自分の講演日程，セッション名，発表形式
・今回の発表内容について簡単に説明
2.2. 質疑応答
今回の講演発表では，以下のような質疑を受けました．
 
・質問内容1
関西学院大学所属の片山淳一先生からの質問です．こちらの質問は12人中8人の値を抜粋してきたのはなぜかというものでした．この質問に対して私は，同じ傾向があったからと答えました．しかしこの解析方法には問題があるということを教えていただきました．多人数のデータを解析する場合，同じ傾向を示すデータだけを持ってくるのは，意図的な処理になるから，全体のデータの値から，統計などを用いて傾向を示す処理をするのが良いというアドバイスをいただきました．
 
・質問内容2
同志社大学の卒業生である藤本恭子さんには，MRIやEEGで同時計測をしたほうが，脳部位の正確な位置を把握できるのではないか，とアドバイスをいただきました．この学会の傾向としても、NIRSよりもMRIやEEGのほうが多かったので，それに対抗出来るだけのNIRSの長所を押し出して行く必要があると思いました．
 
・質問内容3
平田先生GO信号が2000Hzのときは同じ結果が得られるのかという質問をいただきました．月例発表会でも横内先生から同じようなご質問をいただいたため，NOGO信号だけでなく，GO信号も変化させて，検討する必要があると考えられます．
 
質問内容4
スタンフォード大学のHADI HOSSEINIさんには，前頭部の結果がイマイチである．ワーキングメモリ課題では前頭部がよく活性するはずというご指摘をいただきました．また計測プローブに関しては，5プローブのものを使用すると見たい部分(下前頭回周辺)が見れないから，3×11のプローブを用いることを進めるというアドバイスをいただきました．
・質問を簡潔に書く
・質問者の所属と名前を控えていれば書く
・質問に対する回答を書く
 
2.3. 感想
ほかにも多くの質問をいただき、とてもいい機会になりました。英語の能力は予想通り，課題点として挙げられますが，英語力がないとしても，それに屈せず積極的に立ち向かう姿勢が大切だと痛感しました．何事においても挑戦することが大切です．
 
3. 聴講
今回の講演会では，下記の5件の発表を聴講しました．
 

発表タイトル       ：　Differential control of task switching at the local and sequence level in the frontal cortex著者                  ：T. M. DESROCHERS1, D. BADRE1,2; 1Dept. of Cognitive, Linguistic, and Psychological Sci., 2Brown Inst. for Brain Sci., Brown Univ., Providence, RIセッション名       ： Executive function Abstruct            ： Every day we perform tasks that could be characterized by having a superordinate goal that is achieved through multiple sub-goals. Such sequential tasks require multiple transitions, both locally between individual sub-tasks and also at higher levels as sequences are selected based on higher order goals. Behavioral evidence has suggested that local task switching demands can be separated from higher order, sequence level demands. However, it remains unknown whether management of local versus sequence level task transitions is managed by separable systems in the brain. Prior evidence suggests that hierarchical control demands are supported by separate, more rostral, regions of prefrontal cortex relative to lower order control. But this hypothesis has not been tested in the context of hierarchical control over sequences. To address this gap, we scanned participants while they performed short, memorized sequences of simple categorization tasks. For example, a task sequence might be AABB, where task A is a color categorization (e.g., red or blue) and task B a shape categorization (e.g., circle or square). Within this task, we independently manipulated demands on control over local task transitions versus sequence transitions. Specifically, local task control was manipulated by contrasting task switches (e.g., A to B) to task repeats (e.g., A to A) among consecutive tasks regardless of their position in a sequence. Sequence level control was manipulated by contrasting complex sequences, defined as those with more local switches (e.g., ABBA), to simpler sequences (e.g., AABB). The contribution of a hierarchical control process was evident in greater reaction time (RT) at the beginnings of sequences, that was separable from effects due to individual task transitions. Local switching (Task Switch > Task Repeat) was associated with activation in right ventrolateral prefrontal cortex and preSMA. Sequence level control (Complex > Simple sequence) was associated with activation in left inferior frontal sulcus (IFS). Moreover, a parametric analysis revealed that sustained activation in this IFS region over the course of entire 4-element task sequences was associated with a lower initiation cost for that sequence, directly tying activation in this region to efficient establishment of the sequence. Collectively, these results support the hypothesis that control of task sequences is governed by separable areas, and that this control occurs on multiple time scales both at the execution of each task and across the sequence of tasks. These results are considered within the context of current models fronto-striatal systems supporting hierarchical cognitive control.

この発表は課題内容を変化させた時に活性量が変化する部位の検討についての発表でした．課題内容は反応と刺激が単純な場合と，複雑な組み合わせの2パターンであり，私の研究に似た内容でした．刺激と反応の組み合わせを変えるということから，ストループ課題とよく似た課題だという印象を受けました．またこの発表者は英語もままならない私に，丁寧に簡単な言葉でゆっくり話して下さり，とても印象深く残っております．
 

発表タイトル       ：Increased human hippocampal theta oscillations are associated with the maintenance of temporal order information in working memory著者                  ： *L.-T. HSIEH1,2, A. D. EKSTROM2,1, K. SHAHLAIE3, S. T. FARIAS4, M. SEYAL4, C. RANGANATH1,2; 1Ctr. for Neurosci., 2Psychology, 3Neurolog. Surgery, 4Dept. of Neurol., UC Davis, Davis, CAセッション名       ：Working memory Abstruct            ： Several electroencephalography (EEG) studies have suggested that neural oscillations might play a role in working memory (WM) processes. In particular, scalp EEG studies suggest that oscillatory activity in the theta band (4-8 Hz) increases during tasks that require the active maintenance of temporal order information, relative to equally difficult tasks that require maintenance of item features. Little is known about the brain regions that are critical for scalp-recorded theta oscillations, although there is reason to believe that regions in the hippocampus or prefrontal cortex might contribute. Here, we used invasive intracranial EEG recordings from epilepsy patients undergoing presurgical evaluation in order to identify brain regions where oscillatory activity was related to maintenance of temporal order information in WM. Intracranial EEG was recorded while patients completed two types of WM trials: ITEM trials and ORDER trials. On each trial, an instruction word (either “ITEM” or “ORDER”) was shown, followed by four sequentially presented visual objects, and then after a 4 sec retention interval, a test display was shown. On ORDER trials, the test display consisted of two visual objects from the previous sequence, and patients were asked to identify which visual object came earlier in the sequence. On ITEM trials, the test display consisted of one previously presented visual object along with another foil object that was not in the sequence. Patients had to identify which of the two objects was presented in the sequence. Preliminary results from three patients show that hippocampal theta was modulated by maintenance of item and order information. Specifically, two out of the three patients showed that the successful maintenance of temporal order information was associated with enhanced hippocampal theta oscillations as compared to the successful maintenance of item information in WM. These results provide preliminary evidence for the importance of hippocampal theta in maintaining the order of recent events. Further analyses will be performed in order to characterize activity in other regions, including the prefrontal cortex.

2つの課題環境下では、活性部位が左右で異なる。1つの課題は、表示される文字自体に意味を持ち、ある文字が出ると反応を示すもの。もう1つの課題は、その文字自体に意味はなく、前の文字との関係性で意味を持つものでした。前の文字を覚えておくという意味で、ワーキングメモリが使われているという検討がされていました。GO/NOGO課題も同じように、ワーキングメモリが使われていると関連付けられたので、視野を広くして、検討する必要があると考えられます。
 
 

発表タイトル       ：　Longer reaction time is associated with increased task-specific cognitive control and decreased default mode activity著者                  ：A. D. BARBER1,2, B. S. CAFFO3, J. J. PEKAR1,2, S. H. MOSTOFSKY1,2; 1Kennedy Krieger Inst., Baltimore, MD; 2Johns Hopkins Sch. of Med., Baltimore, MD; 3Johns Hopkins Sch. of Publ. Hlth., Baltimore, MDセッション名       ： .Cognition, Learning, and Memory: Neural Mechanisms. Abstruct            ： Within-subject, trial-to-trial fluctuations in reaction time (RT) may reflect fluctuations in attention, integration of information across regions that implement different aspects of the task, or state changes in global network efficiency. Previous studies have found that specific regions are influenced by RT independent of task demands, which may reflect the particular function of the region (e.g. response selection demand). The current study examined RT effects on brain activity in two Go/No-go tasks: a Simple task with an intuitive stimulus-response mapping (green=go, red=no-go) and a Repeat task, with an inconsistent stimulus-response mapping (color change=go, color repeat=no-go), which required working memory for task performance. 22 healthy adults were scanned for two blocks on each task. Image preprocessing and analysis occurred in SPM5. First-level general linear models included up to seven condition trial onset regressors (Post-Rest Go, Go, Go RT, No-go, Commission Error, Omission Error, and Anticipatory trials on which the RT<200 msec), which were convolved with the canonical HRF, temporal and dispersion derivatives. In addition, nuisance regressors (six motion parameters, mean white matter, mean cerebrospinal fluid, and mean whole brain time-courses) and a block regressor for each functional run were included. First-level contrasts of Go RT revealed those regions that increased or decreased activity linearly with RT for the Simple and Repeat Tasks separately. Second-level group effects were examined across subjects. In the Simple Task, slower RT was associated with increased activation in visual (BA 19), inferior and superior temporal (BA 37/39/22), inferior and superior parietal (BA 7/40), and postcentral gyrus (BA 5/2). In the Repeat Task, activation increases with RT occurred within a right frontal region spanning dorso- and ventrolateral cortices (BA 9/44/45/46), anterior insula (BA 13), pre-supplementary motor area and anterior cingulate (BA 6/8/32) and bilateral parietal regions mainly confined to inferior and superior parietal cortex (BA 7/40) with greater extent into supramarginal and angular gyri on the right side. Examination of regions that showed decreased activity with slower RT revealed the medial prefrontal cortex (MPFC: BA 9/10/32) for both tasks. RT modulated activity in a unique set of regions for the two tasks, reflecting task-specific cognitive/attention control. Increased recruitment of these regions may reflect greater deliberate control in slow RT trials. Decreased MPFC activation in slow RT trials may reflect default mode network suppression when control increased.

視覚刺激のGO/NOGO課題を用いて，反応時間と脳活動変化の関係を調べていました．反応時間が増加すると視覚野の反応が大きくなるという結果が得られています．このことから，反応時間は脳活動と密接な関係があることが示唆されているので，私の研究でも成績と脳活動変化の関係性を考える必要があると考えられます．
 

発表タイトル       ：　Increasing functional connectivity with cognitive load著者                  ：L. AHONEN1,2, M. HUOTILAINEN2; 1Työterveyslaitos, Helsinki, Finland; 2Cognitive Sci., Helsinki Univ., Helsinki, Finlandセッション名       ： 573.Working Memory and Executive Function III. Abstruct            ： Studying working memory (WM) with computerized classical cognitive tests is an efficient way to investigate functional activation patterns in brain with different cognitive load levels. The present study investigated neural activity using magnetoenchepalography (MEG) in N-back paradigm. N-back is a task that according to previous research activates large number of WM related brain areas. There are also preliminary results in functional magnetic resonance imaging (fMRI) suggesting that lateral and other inter-areal connectivity between WM associated areas increase during higher cognitive loads. N-back provides precise way to control cognitive load and working memory related activation. We conducted connectivity analysis based on Granger causality to test functional relations between brain regions that have been identified to be task related networks. We focused on load-dependent changes in event-related activity originating from key brain areas in frontal and parietal regions and tested the connectivity in different task conditions. We found increased fronto-parietal and lateral connections with more difficult task conditions. The connectivity was increasing in the direction from frontal areas to parietal areas and between the hemispheres. These results are in line with the previous literature as the number the active brain regions goes up, the connectivity between the related areas become more prominent. These results reveal the functional networking between brain regions during updating and maintaining task dependent information. The connections from frontal regions might generalize to other cognitively demanding tasks

この発表はMEGを用いて，抑制機能のネットワークを調査するというものでした．私がNIRSを使って研究していることを話すと，空間分解能の問題点が挙げられました．ネットワークの調査ではMEGやMRIのほうがふさわしいのかなと改めて考えさせられました．
 

発表タイトル       ：　Effect of visual context on the activation of move- and use-related actions during semantic object processing著者                  ：A. D. SHAPIRO1, S. KALÉNINE2, A. FLUMINI3, A. M. BORGHI3,4, L. J. BUXBAUM1; 1Moss Rehabil. Res. Inst., Elkins Park, PA; 2Lille Nord de France Univ., Lille, France; 3Univ. of Bologna, Bologna, Italy; 4ISTC-CNR, Rome, Italyセッション名       ： Perception: Auditory, Tactile, and Multisensory. Abstruct            ： A number of lines of evidence suggest that observation of manipulable objects activates the motor system (e.g., Chao & Martin, 2000; Craighero, Bello, Fadiga, & Rizzolatti, 2002; Martin, 2007; Noppeney, 2008; Tucker & Ellis, 1998). Many manipulable objects, however, are associated with several actions. For example, a tape dispenser may be grasped with a power grip (clench) to move it, whereas the end of the tape may be grasped with a precision grip (pinch) to use it. Recent studies have shown that object processing may recruit both of these action types (Bub, Masson, & Cree, 2008), and that they may compete with each other within single objects (Jax & Buxbaum, 2010; Jax & Buxbaum, 2013). This study explored the hypothesis that evocation of move- or use-related actions is responsive to the congruence of the visual scene in which objects are presented. Twenty-one healthy adults were asked to categorize object pictures presented in different naturalistic visual contexts that evoke either move- or use-related actions (e.g. tape dispenser in drawer vs. on desk top). Categorization judgments (natural vs. artifact) were performed by making a move- or a use-related action (clench vs. a pinch) on a response device. Categorization reaction times were analyzed as a function of Context (use or move) and Gesture (clench or pinch). Although the actions performed were irrelevant to the categorization judgment, responses were significantly faster when actions were compatible (use context-pinch, move context-clench) compared to incompatible (use context-clench, move context-pinch) with the visual context. Prior demonstrations indicate that action evocation during object processing may be modulated by action intentions (e.g, Pavese & Buxbaum, 2002), distance from the viewer (e.g., Costantini, Ambrosini, Scorolli, & Borghi, 2011), relationships to other objects (Borghi, Flumini, Natraj, & Wheaton, 2012) and verbal context (e.g., Lee, Middleton, Mirman, Kalénine, & Buxbaum, 2013). These data extend such findings by demonstrating that activation of move and use-related gestures during semantic object processing may additionally be modulated by the visual scene in which the objects are presented, with clear implications for object processing in naturalistic tasks.

この発表は自然な行動をするときと人工的な行動をするときでは，人工的な行動をするときのほうが時間がかかるというものでした．他の発表でも反応時間と行動の種類に関して調査しているものが多く，反応は課題内容と密接な関係があることがわかります．反応時間には信号の認知以外にも行動の選択に時間を要していると，いつもと違う視点で考えることができました．
 
 

発表タイトル       ：Acute mild exercise improves cognitive performance associated with arousal-related prefrontal activation: An fNIRS study著者                  ：*K. BYUN1, I. DAN2, K. HYODO1, K. SUWABE1, G. OCHI1, H. SOYA1; 1Univ. of Tsukuba, Tsukuba, Ibaraki-Ken, Japan; 2Chuo Univ., Tokyo, Japanセッション名       ： Cognitive Enhancing Effects of Exercise and Practice. Abstruct            ： A growing number of studies have reported the beneficial influences of acute and chronic exercise on cognition. Our previous study (Yanagisawa et al., 2010) revealed that moderate exercise at 50% V[[unable to display character: ̇]]O2peak enhances executive function via exercise-induced activation of the left dorsolateral prefrontal cortex (l-DLPFC). However, little research has been done concerning whether mild exercise would have beneficial role for cognitive function, and if so, which brain regions get activated. To address this issue, the study aims to examine the effect of mild exercise on cognition and the neural substrate by adopting the Stroop interference (incongruent – neutral contrast), a representative index of executive functions. Twenty-five subjects (mean age, 20.6 ± 1 years; 12 females) participated in two counter-balanced sessions: Exercise (Ex) and Control (Con). In the Ex session, subjects performed a color-word matching Stroop task and a two-dimensional mode scale (TDMS) for measuring psychological arousal levels before and after 10 minutes of the exercise on a cycle ergometer at a low intensity (30% V[[unable to display character: ̇]]O2peak). Cortical hemodynamic changes of the prefrontal area were monitored during the Stroop task in both sessions with a non-invasive functional near-infrared spectroscopy (fNIRS). McNemar’s test was conducted to assess correspondence between behavioural and neural substrates. It was found that mild exercise reduced Stroop interference. Enhanced performance was positively related with arousal levels. As for the neural substrates, cortical activations in response to Stroop interference during the pre-session were detected on the bilateral prefrontal cortex. After the acute mild exercise, brain activations on the l-DLPFC and the left frontopolar area (l-FPA) in association with a higher-order control were enhanced and those elevations were positively correlated with arousal levels as well. The result of the McNemar’s test showed that elicited activations of the l-DLPFC and l-FPA significantly corresponded with improved cognitive performance. These results suggest that acute mild exercise improves executive function, and the effect was mediated in part by activations of the arousal-related prefrontal sub-regions.

この発表は運動する前と運動直後では課題の成績と脳活動にどのような影響があるかというものでした．運動に絡めて，覚醒状態にも焦点を当てており，覚醒状態が認知活動に影響を及ぼしているということが言われていました．覚醒状態の指標にはアンケートが用いられており，改めて覚醒状態を検討することの必要性を感じました．
参考文献
1)    Neuroscience2013, http://www.sfn.org/annual-meeting/neuroscience-2013
 
学会参加報告書
報告者氏名
井上楓彩
発表論文タイトル fNIRS実験時における音圧変化の影響の検討
発表論文英タイトル The effect on changing sound pressure during the measurement using functional Near-Infrare Spectroscopy
著者 井上楓彩, 星野雄地, 山本詩子, 廣安知之
主催 Society for Neuroscience
講演会名 Neuroscience 2013
会場 San Diego Convention Centre
開催日程 2013/11/09-2013/11/13
1. 講演会の詳細
2013/11/09から2013/11/13にかけて, San Diego Convention Centreにて開催されましたNeuroscience 2013に参加いたしました. このNeuroscience 2013は, Society for Neuroscienceによって主催された学会で, 学生と研究者が参加して, 神経系や脳についての研究を行っている研究者たちの交流や, 学術文化発展に寄与することを目的としています.
私は12日のみ参加いたしました. 本研究室からは他に山本先生, 木村, 杉田, 大西, 眞島, 早川, 將積が参加しました.
2. 研究発表
2.1. 発表概要
私は12日の午前のセッション「Working Memory and Executive Function III」に参加いたしました. 発表の形式はポスター発表で，4時間の質疑応答を受けました．
今回の発表は，…．以下に抄録を記載致します．
【目的】
音環境を変化させた際の、数字記憶課題作業時の脳機能の変化について検討した。特に、提示する音の音圧を変化させた際に脳機能の変化が見られるかの検討を行った。
【実験方法】
本研究では作業タスクとして数字記憶課題を選択した。数字記憶課題は、ランダムに表示された8桁の数字を記憶する課題である。被験者は、静音静（48dB）、White noise、Mozart作曲の「2台のピアノのためのソナタ」(以下, Mozart)の環境化でタスクを実行する。さらに、65dBと75dBで呈示し, このときの作業成績と脳血流変化に伴う酸素ヘモグロビン濃度(以下, Oxy-Hb濃度)について調査した。脳血流変化の測定は, 機能的近赤外線分光法装置を用いて計測した.
【結果】
実験結果として, 呈示音の音圧の違いによる作業成績と課題中の脳血流変化の差異は, Mozart呈示時で見受けられ, 一方でWhite noise呈示時では見受けられなかった. 課題中のOxy-Hb濃度の増加については, Mozart呈示時, White noise呈示時ともに上昇の傾向をみせた. 以上より, 音環境下における作業成績と脳血流変化について調査する際は, 呈示音の種類によって, 音圧変化の影響を受けやすいものと, そうでないものがあることに留意する必要性があると示唆された.
【Purpose】
I examined about the influence of brain function during engaging a number memory task with changing sound environment.
Especially, I investigated whether brain function change can be found between two kinds of sound environments.
【Experiment Method】
In this research, I chose number memory task as the working task.
The task shows random eight digits and subjects try to memorise these digits.
The subjects engaged the task with srounded by two kinds of sound environments, which are white noise and “Sonata for Two Pianos in D major(Mozart)” composed by Mozart.
I analysed the task score and Oxy-hemoglobin concentration caused by brain blood flow change while the sound environments were presented 65dB and 75dB.
The brain blood flow change was measured by near infrared spectroscopy.
【Result】
As the result, there were significant differences between two kinds of sound pressure level in terms of task score and cerebral blood flow change.
In other words, the difference was shown when Mozart was presented.
On the other hand, the difference was not shown when white noise was presented.
In addition, the increase of Oxy-hemoglobin concentration was found in both of sound environments.
Therefore, there can be grouped into two types of sounds. The one effected on subjects easily, while the other one was shown otherwise.
In conclusion, it should be noted for choosing sound, when investigated task performance and cerebral blood flow changes in the sound environment.
2.2. 質疑応答
今回の講演発表では，以下のような質疑を受けました．
・質問内容1
こちらは、明治大学大学院 認知脳科学研究室の都地裕樹様から頂いた質問です. 「前頭前皮質背外側部(DLPFC)は左右対称に存在するが, なぜ左側だけに着目したのか.　」と質問を頂きました. これに対して, 「課題成績が音圧レベルの変化に影響をされてしまう被験者群とそうでない被験者群との間で, Oxy-Hb濃度変化にどのような差異が生じるかという点について検討したところ, 左側のDLPFCにおいて差異がみられた. 」とお答えしました. しかし, 計測自体は左側のDLPFCだけではなく, 前頭部と両側頭部で行っていますので群分けに囚われず前領域のOxy-Hb濃度変化について検討する必要があると感じました.
・質問内容2
こちらは, 畿央大学 ニューロリハビリティテーション研究センターの宮崎有希様から頂いた質問です. 今回, 私が発表した研究内容は, 課題成績が音圧レベルの変化に影響をされてしまう被験者とそうでない被験者に群分けをし, 両群のOxy-Hb濃度変化について検討するものでした. しかし, 前者の群に一人, 他と比べて傾向の異なる被験者がいるとご指摘を受けました. 宮崎様のご指摘を受け, 今後, 被験者数を増やし, 再度検討を行う必要があると感じました.
2.3. 感想
fNIRSが日本発祥の技術であることは以前から存じておりましたが, 世界的にはまだまだ普及していない現状を知り, 大変驚きました. 普段の研究室内発表では,fNIRSの測定原理について, 皆さん既に熟知されているので特に詳しく説明する必要はないのですが, Neuroscience では私のポスターを見に来てくださった皆さま全員に, fNIRSについて詳しく説明しなければならず, もっと十分な資料を持参すればよかったと後悔しました.
3. 聴講
今回の講演会では，下記の5件の発表を聴講しました．
発表タイトル ： Dynamics based neural coding in the subjectivity context
著者 ： *K. MOGI; Fund Res. Lab., Sony Comp Sci. Lab.,
Shinagawa-Ku, Japan
セッション名 ： Timing and Temporal Processing
Abstruct ： Disclosure Block: Support: Dynamics is an essential element in the coding of information in the brain (Stein et al. 2005). In analyzing neural codes, the conventional approach has been to apply statistical methods such as signal detection theory (Swets 1964) or integrated information theory (Tononi 1998). Such an approach has provided useful insights into the functions of the brain and principles of perception and cognition. A statistical approach can be enhanced further by incorporating the dynamics and structure of the system explicitly. Key to such a treatment is the explicit and dynamic choice of the “ensembles” with which the statistical properties of a system are analyzed.A number of experimental data and theoretical analysis have suggested that perception is an active process, where the hypotheses and internal models based on past experience are “matched” with the incoming sensory data. It is thus likely that the dynamic choice of ensembles by the cortical neural network is implemented in this matching process.Here I present an analysis of the necessary conditions for the construction of a dynamics based neural coding, citing relevant evidence from the measurement of neural firings in the brain. Strategies for the study of neural information processing in the era of big data on brain anatomy and function are presented.A model for dynamics-embedded ensemble formation is presented, with the subjectivity structure explicitly given. In this model, time is an essential element constructed actively, on which a spectrum of neural codes are defined. Psychological time generated from the neural activities is in general different from the physical time. It is proposed that the excitatory, inhibitory, and modulatory connections within the neural network contribute to the construction of subjective time in different manners. Finally, I discuss how the semantics of information can be implemented in a coding system based on dynamics and embedded in the subjectivity context.
脳科学研究の第一人者である, 茂木健一郎先生のポスター発表を間近で聴くことができ, 大変貴重な体験を致しました. 今回, 茂木先生が発表されていた研究は, タスクの難易度によって被験者が定性的に感じる時間の長さと, 実際の定量的な時間の長さには負の相関性があるというものでした. 日頃から私自身も難しい課題に取り組んでいるときは, 長時間それに従事していても, あっと言う間に時間が過ぎ去ったかのような錯覚を覚えることがあります. そのような日常の事柄を改めて実験により証明した, 茂木先生の研究アプローチに, いたく感銘を受けました.
普段, 茂木先生がＴＶ出演をなさるとき, 脳科学に詳しくない人にでも分かりやすいように, 噛み砕いでお話してくださるのですが, 本学会においてはそうではありませんでした. 高度な科学者目線で研究内容を説明されたので, 私はその話についていくのが精一杯でした. この苦い経験を活かし、次に繋げていきたいと思います.
発表タイトル ： Test date expectancy affects memory performance
著者 ： *R. E. LOIOTILE1, R. A. ADCOCK3,4,
S. M. COURTNEY1,2,5;1Psychological and Brain Sci.,
2Neurosci., Johns Hopkins Univ.,
Baltimore, MD; 3Ctr. for Cognitive Neurosci.,
4Dept. of Psychiatry, Duke Univ., Durham, NC; 5F.
M. Kirby Res. Ctr., Kennedy Krieger Inst., Baltimore, MD
セッション名 ： Human Long-Term Memory: Encoding
Abstruct ： Though several studies have examined the role of test expectations– e.g. expectations of test type and test consequences– on subsequent performance, surprisingly little is known on the role of test date expectations, specifically. Knowledge of test dates certainly affects how students distribute their study time, a learning factor that has been investigated since the birth of memory research. But, irrespective of study-time distribution, does knowledge of the expected test date affect one’s encoding of the material?Our study, therefore, seeks to determine the effects of expected test date on memory performance. We hypothesized (1) that individuals would alter their learning strategies, perhaps even unbeknownst to themselves, to benefit expectations of longer retrieval delays or (2) that certain test dates– e.g., those closer to the present– would induce differential pre-learning motivation or preparedness to learn.Our experiment tested recognition on a set of 120 emotionally neutral scene stimuli in twenty subjects. Subjects were informed that half of the stimuli would be tested today (i.e., 30 minutes after encoding), half would be tested tomorrow (i.e., 23-25 hours after encoding), and that they would be informed of each scene’s test date by a pre- (and during-) scene cue reading “today” or “tomorrow.” Critically, subsequent recognition tests ignored the advertised test dates. Subjects were tested on half of the stimuli from each test-date cue on each test date. For example, 30 today-cued scenes were tested at “today,” and the remaining 30 today-cued scenes were tested at “tomorrow.”Analysis revealed a significant main effect of cue date on memory performance. On average, subjects remembered today-cued stimuli better than tomorrow-cued stimuli on both “today” and “tomorrow” tests, with the latter showing a significant difference. Our results indicate that despite monetary incentives to perform as well as possible on both “today” and “tomorrow” tests, independently, subjects were more motivated– some admittedly, others unknowingly– to memorize the stimuli they thought would be appearing on “today’s” test.Future fMRI work will attempt to ascertain the neural mechanisms of this differential memory performance. In particular we would like to examine whether today-cued stimuli, independent of memory performance, are correlated with differential increases in midbrain activation, similar to cuing effects of expected monetary rewards. Overall, our study demonstrates a strong effect of test date expectations on learning, independent of study time and distribution.
本学会では、fNIRSを用いた研究はまだまだ少数派であり、脳計測機器としてfMRIやEEGが使われた研究が盛んであるという印象をうけました. この研究は、試験日とメモリパフォーマンスとの間にどのような脳活性がみられるか, fMRIを用いて計測したものです. この研究結果では, 中脳の活性より, 被験者は試験日が近づくにつれ, メモリーパフォーマンスが増加するというものでした.
発表タイトル ： Facilitatory role of playing music during exercise in executive
function: A neuroimaging study with functional near-infrared
spectroscopy
著者 ： *K. SUWABE1, I. DAN2, K. HYODO1, K. BYUN1, G. OCHI1;
1Univ. of Tsukuba, Tsukuba City, Japan; 2Chuo Univ., Tokyo,
K. Suwabe: None. I. Dan:None. K. Hyodo: None. K. Byun:
None. G. Ochi: None.
セッション名 ： Cognitive Enhancing Effects of Exercise and Practice
Abstruct ： The benefits of acute and chronic exercise on human cognitive functions have been given a great deal of attention. One of our recent studies has shown for the first time that acute moderate exercise (at 50% VO2peak) elicits increased brain activation in the left-dorsolateral prefrontal cortex (DLPFC), which results in improved Stroop task performance (Yanagisawa et al., NeuroImage, 2010). The DLPFC plays a role in the modulation of mood as well as executive function: activation in the left DLPFC enhances positive emotional affects (Ueda et al., 2003; Herrington et al., 2005). Hence, it is postulated that listening to one’s favorite music while exercising may elicit greater activation in the DLPFC, leading to enhanced executive functions. To address this issue, twenty-six subjects (mean age 21.6 ± 2.4 years, 8 females) participated in two experimental conditions (exercise with music or with a beep at a steady tempo). Subjects performed a color-word matching Stroop task (CWST) and two-dimensional mood scale (TDMS) before and after 10 minutes of moderate intensity exercise (50% of VO2peak). Using multichannel functional near-infrared spectroscopy (fNIRS), cortical-activation-related changes in the CWST were examined. Results demonstrated that the music condition evoked a more positive valence compared to the tempo condition. However, no significant differences were observed between the two conditions in CWST performance or Stroop-interference-related activation in any prefrontal regions. Interestingly, there were positive correlations between valence changes and CWST performance changes, and valence changes and cortical activation changes in the left DLPFC. These results suggest a facilitatory role of playing music during moderate exercise in the development of enhanced executive functions induced by exercise.
この方は, 音楽を聞きながら運動したときの脳活動の様子を研究されていました. また, 学会参加者のなかでも珍しい, fNIRSを使った脳血流変化の測定を行っている研究グループでした. 私たちの研究室で日立製のfNIRSを使っていますが、この方の研究室では島津製作所製のものを使っているとのことでしたので, 詳細について教えて頂きました. 今後、私たちMISLでも島津製作所製のfNIRSに触れる機会がありますが, 日立製と島津製を比較するに, 島津製のほうが測定部位に対する応用が効く一方, 操作に関しては日立製より複雑であるという印象を受けました.
また, 研究内容に関してですが, 「運動をしている最中の脳血流変化の測定」と聴いて, 一体どのように測定しているのか大変興味を持ちました. なぜなら, 脳血流変化というのは非常に繊細なデータであり, ほんの少しの体動でも大きな誤差を生じさせてしまうからです. 発表者のお話を聞いたところ, 自転車のペダルのような機械を用い, 被験者には脚だけを動かしてもらったらしいです. この方の研究結果では, 音楽を聴いて運動すると気分が爽快になりやすい傾向にある, とのことでした. 音楽を聞きながらランニングの記録が取れるスマホアプリが開発されているが, 運動中に音楽を聞くということは, 脳科学的にもその有用性が示されたと感じました.
発表タイトル ： Real-time neuro-feedback training of executive functions
in healthy adults: A functional NIRS study
著者 ： *H. HOSSEINI1, S. R. KESLER1,2; 1Dept. of Psychiatry and
Behavioral Sciences, Sch. of Med., Stanford Univ.,
Stanford, CA; 2Stanford Cancer Inst., Palo Alto, CA
セッション名 ： Congnitive Enhancing Effects of Exercise and Practice
Abstruct ： Cognitive training is an emergent approach that has been adopted in recent years as a potential intervention for a number of developmental and neurodegenerative disorders. Cognitive training theoretically promotes several neuroplastic mechanisms in the brain and has been shown to improve cognitive functioning in various healthy and patient populations. The main goal of cognitive training is to boost/restore cognitive skills and brain function by employing a set of adaptive, practice-based paradigms.
In order for the training programs to be effective, individuals are usually asked to perform a distributed set of cognitive training paradigms. This approach has several disadvantages. First, the training time can be lengthy (1 to 6 months), making adherence potentially difficult for patients with cognitive difficulties. Second, there is no guarantee that the training will be helpful for a specific individual. Third, the efficacy of the training is usually tested after the end of the training neglecting potentially interesting learning effects at other time points. In the present study, we developed a real-time neuro-feedback training program that addresses some of the limitations of conventional training methods by providing real-time feedback regarding brain activity in targeted regions. We focused on training executive functions (EFs) given their core involvement in various developmental and neurodegerative diseases. Near-infrared spectroscopy (NIRS), which is a cost-effective and ecologically-valid brain imaging method, was employed for measuring brain activity in the prefrontal cortex.
Our preliminary data on 10 healthy adults (5 female, age range 18 to 40) showed four sessions of EF training (100 min total) with neuro-feedback significantly improved EF. Specifically, subjects’ performance on standardized EF tests including measures of verbal and visual working memory as well as inhibition/switching were significantly improved (p < 0.05). In addition, we compared the neuro-feedback training results with those of a parallel study in which we examined the effect of computerized EF training (24 sessions each lasting 20 min in 6 weeks) on 18 healthy subjects (9 females, age range 18 to 40). Despite the significantly lower duration of the neuro-feedback training (100 min vs. 480 min), the increase in inhibition/switching performance was slightly higher in the neuro-feedback training group compared with the computerized training group. Our data suggest that providing neuro-feedback may improve the efficiency of cognitive training paradigms making it more feasible for certain patient populations.
NIRSが日本発祥の技術であることは以前から知っていましたが, 海外では未だ浸透していない現状に驚きました. そのなかでも, スタンフォード大学では島津製作所製のNIRSを所有し, これを用いた研究が行われていると知って, 大変興味を持ちました. この研究の発表者は, 以前, 東北大学の川島隆太先生のもとで留学をされていたそうです. 川島先生の研究室でもNIRSを使っているらしく, その縁で, アメリカに戻ってからもNIRSを使い続けていると仰っていました. この方は, ニューロフィードバックについて研究されていました. 私は, ニュードフィードバックに関しては今まで無知で, また英語でのポスター発表であったので, 当初, 理解するのに苦労しました. ニューロフィードバックとは, 脳内の計算や記憶などを司る部位を活性させるために, それらと関連した他の部位を活性させる研究のことです. この方の研究では, 認知障害を持つ患者においても, ニューロフィードバックトレーニングが認知訓練のパラダイム向上に有効であるという報告をされていました.
発表タイトル ： On the practice of replicating an electrophysiology study
with the Center for Open Science
著者 ： *M. LEWIS, M. PITTS; Psychology, Reed Col., Portland, OR
セッション名 ： Ethics and Policy
Abstruct ： Replicability is essential to scientific progress. However, in recent years published research findings have been less reproducible. Recently, an initiative called the Reproducibility Project (RP) has been organized by the Center for Open Science (COS), a non-profit organization seeking to establish infrastructure for scientists to make their research process more transparent. The goal of the RP is to test the reproducibility rate of published research findings as well as to develop methods to improve the practice and dissemination of direct replication experiments. Currently, over 100 scientists have joined a single endeavor to replicate experiments published in three prominent psychology journals: Psychological Science, Journal of Experimental Psychology: Learning, Memory, and Cognition, and Journal of Personality and Social Psychology. Participation in the RP entails collaboration with other members of the COS as well as the authors of the original study to develop strategies for adhering as closely as possible to the original experiment. While the RP and COS were originally developed by cognitive scientists and social psychologists, such endeavors are likely to be of interest and utility to the neurosciences as well. Here, we discuss first-hand experience in conducting a replication experiment as part of the RP, from experimental design and data analysis to the submission of a complete report to the COS. Relevant to the neurosciences, this particular replication experiment involved electroencephalographic (EEG) and electromyographic (EMG) recordings associated with motivational aspects of error monitoring. This study not only contributed to the larger RP, but also provided unique training opportunities for students in neuroscientific techniques as well as exposure to the open science approach. The challenges involved in maintaining strict adherence to the methods and analyses of the original study prompted development of practices to efficiently share experimental materials and data. A number of potential solutions to the problems of openly encoding and providing access to neuroscientific and behavioral data will be discussed.
この方はEEGを用いた研究をされている方でした. 被験者にWhite noiseを聴かせたときの脳波を計測されていて, 私もfNIRSで音環境の研究を行っているので, 興味を持ちました. この実験では, 被験者はWhite noiseを一瞬だけ聞かされます. 私の実験では、White noiseを5分近く再生するのですが, White noiseを再生する瞬間は被験者を驚かせてしまうのか, 体動が生じてしまうことが多々あります. EEGはfNIRSよりも体動に敏感な装置なので, 計測中に体動が起きないのか疑問に思いました. これについては, 被験者に聴かせるWhite noiseは一瞬であるため, 体動はなかなか生じにくいというものでした.
参考文献
1) Neuroscience 2013 Daily Books, http://www.sfn.org/annual-meeting/neuroscience-2013/abstracts-and-sessions/program