Anterior limbic unit activity during delayed response in cats

The extracellular activity of 328 units was recorded from the anterior limbic cortex of cats performing a spatial delayed response task (DR). The DR task required the cat to make a lever-press response after a delay period of a few seconds to a previously cued location. Of the cells recorded, 139 (42%) showed some relation to DR performance. Task-related units were assigned to one of eight class and type categories consistent with the cell's active phase during the trial periods. Class B units, 23% of the total number of cells recorded, responded during the cue and choice lights. Class C units, 9% of the total recorded, were responsive to the cue and throughout the delay until the lever-press response. Class D units, 4% of the total, were related to the delay phase of DR only. Class E units, 6% of the cells, were active during the cue and displayed activity opposite in sign during the delay. Differential reactivity of units for left and right trials were observed for some units in the B,C, and E response categories, including some cells displaying differential activity during the delay period. It is concluded that visually driven sensory units typically responded to the cue and choice lights, whereas delay related units appeared to represent an intrinsic process, without postural or other external concomitants.