ナカムラ　カエ   NAKAMURA KAE   中村　加枝    所属   関西医科大学  生理学講座    職種   教授
言語種別	日本語
発表タイトル	サル視床下部外側野における報酬情報表現は部位により異なる Rward-coding by the primate lateral hypothalamus is spatially distinct.
会議名	第33回　日本神経科学大会
学会区分	全国規模の学会
発表形式	ポスター掲示
講演区分	一般
発表者・共同発表者	◎Noritake,A., Nakamura, K.
発表年月日	2010/09
開催地 （都市, 国名）	神戸
概要	The lateral hypothalamus (LH) has connections with areas involved in reward processing such as ventral tegmental area, nucleus accumbens, amygdala, septum, and dorsal raphe nucleus.To study the nature of reward information encoded in primate LH, we recorded single LH neurons while a monkey performing asymmetrically rewarded visually-guided saccade tasks. In a given block, one of two target cue positions was associated with a large reward and the other with a small reward. The cue position - reward size association was switched every 16-20 trials. Among neurons which showed significant modulation by events such as fixation onset, target onset, saccade, and/or reward delivery(n=130), many neurons showed significant modulation in activity by the expected reward size with either large or small reward preference after cue onset only (n=26), after reward only (n =33), or after both cue and reward (n= 21). Within neurons which showed reward-dependent modulation after both cue and reward, more than half of them (n = 15/21) showed stronger response to small-reward indicating cue and small-reward delivery, while the rest 6 neurons showed stronger response to large-reward indicating cue and large-reward delivery. Such biased distribution was not evident for the cue-only or the reward-only related neurons (large vs small preference, n=13 vs 13, and n=18 vs 15, respectively). We also found that the representation of reward effects during the post-reward period was spatially specific. Neurons in the rostral part of the LH tended to show stronger response for the small-reward than large-reward delivery while neurons in the caudal part tended to show stronger response for the large-reward than the small-reward delivery. We conclude that the primate LH neurons code reward size and that reward information is computed in a spatially specific manner, which may be partly due to the anatomical connection with different brain areas.