Neuronal activity in the ventral part of premotor cortex during target-reach movement is modulated by direction of gaze

J Neurophysiol. 1997 Jul;78(1):567-71. doi: 10.1152/jn.1997.78.1.567.


We recorded 200 neurons from the ventral part of the premotor cortex (PMv) and 110 neurons from the primary motor cortex (MI) of a monkey performing a visually cued arm-reaching task with a delay. We compared neuronal activity in the premovement period while the monkey reached the target with the eyes fixating on either a left or right fixation target. Our data demonstrate that about half of the movement-related activity in the PMv was modulated by the direction of gaze. In contrast, a vast majority of the activity of MI neurons and about half of PMv neurons were not influenced by the direction of gaze. We further analyzed the movement-related activity during the reaching movement to targets at the top, bottom, left, and right of each fixation point. The magnitude of activity of neurons showing the gaze-direction selectivity was primarily determined by the position of the reaching target relative to the eye-fixation target, and not by the position of the target relative to the animal's body. These data suggest that a part of the coordinate transformation of the motor command signals concerning the direction of reaching from the retinotopic to body-centered frame of reference may occur at the level of premotor cortex but not in MI.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arm
  • Cues
  • Fixation, Ocular / physiology*
  • Macaca
  • Motor Cortex / cytology
  • Motor Cortex / physiology*
  • Movement / physiology*
  • Neurons / physiology*
  • Psychomotor Performance / physiology*