Task-dependent selectivity of movement-related neuronal activity in the primate prefrontal cortex

We studied movement-related neuronal activity in the dorsolateral prefronta l cortex from the perspective of a general role for the prefrontal cortex i n controlling motor behavior to achieve a specific goal according to the re quirements of a given task. Monkeys were trained to perform two delayed mot or tasks. The first task involved reaching for a target that matched the sh ape of a cue. The second task involved reaching for a target that matched t he location of the cue. A majority (54%) of 175 movement-related prefrontal neurons exhibited preference for either the target shape or the type of ta sk requirements. Sixty-four neurons (34%) were selectively active while rea ching for a circle or a triangle. On the other hand, the activity of 59 neu rons (34%) depended on whether the task required matching the shape or the location. These properties, characterizing the movement-related neuronal ac tivity in the prefrontal cortex, rarely were found in the arm area of the p rimary motor cortex. Only 1 of 130 movement-related neurons (0.8%) showed t ask selectivity, and none showed target-shape selectivity.