演題詳細
Poster
運動課題遂行中のラットにおける運動野細胞の同期的活動の集団特性
Population characteristics of spike synchrony in rat motor cortices during movement task
- P1-150
- 木村 梨絵 / Rie Kimura:1,2,4 酒井 裕 / Yutaka Sakai:1 齊木 愛希子 / Akiko Saiki:1,2 塚元 葉子 / Yoko Fujiwara-Tsukamoto:1,2,3 礒村 宜和 / Yoshikazu Isomura:1,2
- 1:玉川大・脳研 / Brain Sci Inst, Tamagawa Univ, Tokyo, Japan 2:科学技術振興機構・CREST / JST-CREST, Tokyo, Japan 3:同志社大・脳科学 / Grad Sch Brain Sci, Doshisha Univ, Kyoto, Japan 4:生理研・生体情報・視覚情報処理 / Division of Visual Information Processing, NIPS, Okazaki, Japan
Our previous study reported that many neurons of motor cortex of rats, which may be responsible for various motor phases, often discharge synchronously within several milliseconds. The spike synchrony has been considered to be functionally important. However, little is known about what characteristic features synchronous activities have in populations, depending on motor functions and situations. It is also known that in primates an external and internal signal activates premotor cortex and supplementary motor cortex, respectively. However, it remains unknown whether in rodents different motor cortices control externally- and internally-initiated movements and how cortical local circuits control those movements. Here, we examined neuronal activities and their spike synchrony from deep layer in primary (M1) and secondary motor cortex (M2) of rats performing an operant behavioral task under a head-fixed condition. The operant behavioral task required the rats to pull a lever using their forelimb in response to a cue tone (external trials) or pull it spontaneously without the cue (internal trials) after waiting for at least one second. We found that synchronous activities are stable and little dependent on motor functions, and that different types of motor initiation are represented not as synchronous activities but as difference of firing rate in M2. Both M1 and M2 basically show comparatively similar neuronal activities, however M2 seems to carry more modifiable functions. The changeability in synchronous activities was almost stochastic in population, suggesting the stability may enable a reliable motor execution.