NEURONAL ACTIVITY IN THE PREFRONTAL CORTEX IN RELATION TO SEQUENTIAL PERFORMANCE OF CATEGORIZED MULTIPLE MOVEMENTS

本研究的目的是研究前额叶皮质的神经元活动如何参与分类的多重运动的执行。我们训练一只猴子按顺序做四个动作，中间有短暂的等待期。在一种情况下，视觉信号(三种不同颜色的LED)指示要执行什么动作。在另一种情况下，必须记住正确的前向动作顺序。肌电分析表明，在两种情况下，肌肉活动的大小相同。在等待期间，前肢肌肉的活动变化不明显。动物进行了11种多动作，分为三种类型；单系列型(Push-Push、Pull-Pull、Turn-Turn)、交替系列型(Push-Turn-Push-Turn、Pull-Turn-Turn-Turn、Turn-Push-Turn-Push、Turn-Pull-Turn-Pull)和配对系列型(Push-Push-Turn、Pull-Pull-Turn-Turn、Tunr-Turn-Push-Push、Turn-Turn-Pull-Pull)。其中77个神经元在第一个等待期活动增加。其中单系型11个，交替系列型23个，配对系列型19个。额叶视野中未记录到这种活动。这些结果表明，前额叶皮质参与了多个动作顺序表现的分类。

The purpose of the present study was to examine how neuronal activity in the prefrontal cortex is involved in performance of categorized multiple movements. We trained a monkey to perform four movements sequentially, separated by brief waiting periods. In one condition, a visual signal (LED of three different colors) indicated what movement to be performed. In the other condition, correct sequences of fore movements had to be remembered. EMG analyses showed that magnitude of muscle activities were equal in the two conditions. Activity change in forelimb muscle were not detectable during waiting periods. Animal was performed 11 kinds of multiple movements, which are categorized in three patterns; mono-series type (push-push-push-push, pull-pull-pull-pull, turn-turn-turn-turn), alternate series type (push-turn-push-turn, pull-turn-pull-turn, turn-push-turn-push, turn-pull-turn-pull), and paired series type (push-push-turn-turn, pull-pull-turn-turn, tunr-turn-push-push, turn-turn-pull-pull).241 task-related neurons were recorded in the prefrontal cortex. Among them 77 neurons shdwed increased activity in first waiting period. 53 of 77 neurons were belonged to the one of three patterns; mono-series type 11; alternate series type 23; paired series type 19. Many neurons were recorded in and around the principal sulcus, especially in the upper part of principal snlcus. Such activities were not recorded in frontal eye field. These results indicate prefrontal cortex participate in categorization of sequential performance of multiple movements