[Cell activities in primate areas F2 and F4 of the monkey during memorized spatial motor task]

Single-cell activities were recorded in the area F2 of dorsal premotor cortex (PMd) and area F4 of ventral premotor cortex (PMv) while a monkey was performing a memorized spatial motor task of sequence (MSS). For the task of MSS-G, using green light as a cue during the cue period, 78.2% and 41.5% of the task-related neurons exhibited changes in activities in the areas F2 and F4, respectively( (2) 15.2, P<0.005), whereas there were more neurons exhibiting changes in activities in F4 than in F2 during the image and the touch periods. The differences were both statistically significant. Similar results were obtained for the task of MSS-R using red light as a cue. Furthermore, there were more cells responding to the cue signal in F2 than in F4, while the situation was reversed during the image and touch periods. The present findings indicate that neurons in the PMd and PMv examined are differentially involved in the MSS task.