前頭連合野の運動機能—高次運動野の認知的行動制御

Functional Parcellation of Frontal Higher Order Motor Cortex

前頭葉の運動関連領野は皮質の内側，外側にそれぞれ複数存在する。外側に位置する運動前野群は，感覚の空間的な側面やルールに基づいた運動の制御に関わる。一方で内側，特に補足運動野群は両手協調，運動の順序・時間的制御に関わる。帯状皮質運動野は報酬予測誤差に基づいた動作維持や更新に関わる。さらに運動野は行為主体性の形成，他者理解など高次脳機能に貢献している実態が明らかになりつつある。

Abstract

Motor areas in the frontal cortex are classified into medial and lateral functional groups. The dorsal premotor areas in the lateral groups are involved in motor guidance based on behavioral rules. The ventral premotor cortex contributes to motor guidance relying on spatial aspects of sensory information. The supplementary motor complex in the medial groups is related to the bimanual and temporal organization of multiple motor acts. The cingulate motor area is involved in motor control based on reward-prediction errors. The supplementary eye field is involved in monitoring performance and the adjustment of sequential visual search. The motor areas are coordinated in a context-dependent manner, influenced by top-down signals from the prefrontal cortex and by bottom-up signals from the parietal cortex, which are also organized into the lateral and medial functional groups. Evidence suggests that the medial and lateral functional groups are balanced by the insula cortex and anterior cingulate cortex which serve as salience detectors for changes in bodily states.