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he internal action plan while responding to the exigencies of the local stimulusnvironment, we trained a monkey to perform a memory-guided sequential motorask that included planned interruptions. Experimental sessions were sectioned offccording to the temporal order of the motor sequence the animal had to repeatedlyerform (main-task). While the main-task was interrupted, the animal had to executemovement instructed by a visual cue, independently from the main task. Thereafter,

he animal resumed the main-task and was required to recall a motor sequence itreviously performed. We recorded neuronal activity from the prefrontal cortexhile the animal was interrupted during the sequential motor task. We studied the

ctivity of neurons related to this interruption.

oi:10.1016/j.neures.2009.09.1327

3-i11 Categorical coding of stimulus-outcome association in theorsolateral prefrontal cortexunekazu Yamada, Yuta Sato, Maria del Carmen Romero Pita,

oshio Iijima, Ken-Ichiro TsutsuiDiv. of Sys. Neurosci., Grad. Sch. of Life Sci., Tohoku Univ., Sendai, Japan

onkeys were trained to perform a repeated group-reversal task, which requiredearning and reversals of the associations between visual cues and their outcomesappetitive or aversive liquid). We recorded single-unit activity in the dorsolateralrefrontal cortex (DLFPC) during the task performance. Most of the visually respon-ive neurons in the DLPFC showed the same level of response to all cues associatedith the same outcome. The selectivity of these neurons for appetitive or aversiveutcomes was constant over the reversal of stimulus-outcome associations, whichppeared as a drastic reversal of visual selectivity at each reversal. Such activityay suggest that the DLPFC is involved in the coding of stimulus-reward outcome

ased on stimulus category, but may not be involved in the storage of the memoryf stimulus category.

oi:10.1016/j.neures.2009.09.1328

3-i12 Neural basis for associative memory of faces in the monkeynterior inferior temporal cortexatoshi Eifuku, Yoshio Daimon, Ryuzaburo Nakata, Michiyaugimori, Taketoshi Ono, Ryoi Tamura

Univ. Toyama, Japan

o investigate the neural basis for memory of facial identities, we recorded neuronalctivities from the area AITv of monkeys during the performance of an asymmet-ical paired association task between facial identities and pictorial patterns. Theesults showed that some AITv neurons responded selectively to a particular pairassociative pair–selective neurons) and indicated a tuning to facial views, implyingview-specific representation of facial identity. Meanwhile, the population of theITv neurons with significant selectivity for faces well represented facial identity,hich was view-invariant. Some AITv neurons showed sustained activities during

he inter-stimulus delays that were selective for a particular facial identity. Furthernvestigation of these sustained delay activities suggested that they occurred onlyhen a view-invariant facial identity had to be recalled, which supported the notionf a view-invariant representation of facial identity during retrieval. These resultsuggest a functional neural organization in the AITv.

oi:10.1016/j.neures.2009.09.1329

3-i13 Neural basis of episode context: an fMRI studyotoaki Sugiura1, Yukihito Yomogida1,2, Toshimune Kambara1,

oko Mano1, Atsushi Sekiguchi1, Takashi Tsukiura1, Ryutaawashima1,3

IDAC, Tohoku Univ., Japan; 2 JSPS, Tokyo, Japan; 3 JST/RISTEX, Tokyo,apan

eural correlates of episodic context where multiple items are associated werexamined. In an encoding session, subjects played a role of detective in 24 episodes.n each episode, six items (faces or objects) were involved. During an fMRI ses-ion, subjects performed item recognition test in a block where all the items wererom the same episode (Same), or in a block where all the items were from differ-nt episodes (Diff). We assumed that the neural representation of episodic contextxhibits diminished response in the Same blocks due to the repeated processingf the same episodic context (i.e., neural adaptation). Decreased activation in the

ame relative to the Diff blocks was observed in the left hippocampus and ante-ior inferior temporal gyrus, suggesting a role of these regions in representation ofpisodic context.

oi:10.1016/j.neures.2009.09.1330

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3-i14 Neural correlates of long-term associative memory in humanemporal cortexeiki Konishi1, Ken-ichiro Yamashita1, Satoshi Hirose1, Akiraunimatsu2, Shigeki Aoki2, Junichi Chikazoe1, Koji Jimura1,oshitaka Masutani2, Osamu Abe2, Kuni Ohtomo2, Yasushiiyashita1

Dept. Physiol, Univ. of Tokyo, Tokyo, Japan; 2 Dept. Radiol, Univ. of Tokyo,okyo, Japan

n this fMRI study, we detected the brain activity in the temporal neocortex thatas developed about 8 weeks after study of unfamiliar pictorial paired associates.

wo sets of paired Fourier figures were studied, one about 8 weeks before testRemote memory) and the other immediately before test (Recent memory), keepinghe correct performance during the tests balanced across the two sets of stimuli.ecent memory elicited significantly greater signal in the hippocampus, whereas

emote memory elicited significant greater signal in the anterior temporal cortex.he greater activity during retrieval of older memory developed in the temporal neo-ortex provides direct evidence of formation of temporal neocortical representationor stable long-term memory.

oi:10.1016/j.neures.2009.09.1331

3-i16 Reinforcement learning strategies for sequential actionearninglan Fermin1,2, Yoshida Takehiko1,2, Saori Tanaka3,4, Makoto

to1, Junichiro Yoshimoto1,2, Kenji Doya1,2,3

OIST, Japan; 2 NAIST, Japan; 3 ATR, Japan; 4 ISER Osaka University, Japan

o investigate whether and how humans utilize Model-Free (MF) and Model-BasedMB) action selection strategies, we performed an fMRI experiment using a gridailing task. Subjects moved a cursor to a goal in a 5 × 5 grid sequentially press-ng three keys. Start position color (green/red) specified immediate or delayed4–6 s) start and the cursor shape a key-map rule. Behavior analysis under threeonditions, (1) learned key-map and start-goal pairs, (2) learned key-map for newtart-goal pairs, (3) new key-map for new start-goal pairs, showed subjects uti-ized MB strategy in condition (2) with delayed start. Imaging analysis revealedistinct delay-period activity in each condition: (1) left putamen, dorsal premotornd somatosensory cortices, right cerebellum; (2) left dorsolateral prefrontal areasBA46,47), ventral premotor areas, posterior cerebellum, visual cortex (BA18), rightentral premotor area; (3) parietal areas related to somatosensory/visuo-spatial pro-essing (BA2,7,23,40,19) bilaterally. Areas activated in condition (2) are candidateetworks for MB action planning.

oi:10.1016/j.neures.2009.09.1332

3-i17 Implementing temporal-difference learning throughopamine-modulated plasticityiebke Potjans1,2, Abigail Morrison2, Markus Diesmann2,3,4

Research Center Juelich, Germany; 2 RIKEN Brain Science Institute, Wako-hi, Japan; 3 RIKEN Computational Science Research Program, Wako-shi,apan; 4 Bernstein Center for Computational Neuroscience, Freiburg, Ger-any

ynaptic plasticity is thought to underlie learning, however, the exact relationetween changes in synaptic efficacy and system-level learning remains unclear.e address actor-critic temporal-difference (TD) learning in a spiking neural net-ork. Our network model generates dopaminergic activity representing the TD error

ignal. This dopamine signal modulates the corticostriatal plasticity as a third factor.lthough the synaptic plasticity rules were postulated using a top-down approach,

here is excellent agreement between the predictions of our synapse model andxperimental findings. We show that the network can solve a non-trivial grid-worldask with sparse rewards. The learning performance is similar to that of a discrete-ime TD learning algorithm.

oi:10.1016/j.neures.2009.09.1333

3-i18 The evolving recurrent network of oscillatory neurons orga-ized through the synaptic plasticityakaaki Aoki, Toshio Aoyagi

Grad. Sch. of Informatics, Kyoto Univ., Kyoto, Japan

eural network is adaptively modulated by synaptic plasticity, depending on theeural activity. To investigate the fundamental properties possessed by such andaptive network, we present a simple mathematical model of the evolving recur-ent network of oscillatory neurons. The plasticity is incorporated by allowing the