Delay-related activity in the primate prefrontal cortex during sequential reaching tasks with delay

Neurosci Res. 1993 Nov;18(2):171-5. doi: 10.1016/0168-0102(93)90019-m.

Abstract

To investigate how prefrontal neurons store multiple spatial locations simultaneously, neuronal activity during delay was analyzed while a monkey performed a delayed sequential reaching (DSR) task, in which the monkey was required to store both locations and the order of two sequentially presented targets during delay, and a delayed reaching (DR) task with single target. 38 out of 61 task-related neurons showed delay-related activity and were classified into three types. Type 1 (58%) showed delay-related activity depending upon the direction of the first reaching movement. Type 2 (21%) showed delay-related activity depending upon whether the reaching cue was presented at either left or right. Type 3 (21%) showed delay-related activity nonspecifically during all trials of both DSR and DR. Neurons with delay-related activity only in DSR trials were not observed. These results suggest that each prefrontal neuron may not hold information for the whole sequence of a complex movement during delay, but may hold partial information of that movement, such as one target location or one movement direction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cues
  • Electrophysiology
  • Hand / physiology
  • Macaca mulatta
  • Male
  • Memory, Short-Term / physiology
  • Microelectrodes
  • Movement / physiology*
  • Neurons / physiology
  • Prefrontal Cortex / cytology
  • Prefrontal Cortex / physiology*
  • Space Perception / physiology*