Non-spatial, motor-specific activation in posterior parietal cortex.
A localized cluster of neurons in macaque posterior parietal cortex, termed the parietal reach region (PRR), is activated when a reach is planned to a visible or remembered target. To explore the role of PRR in sensorimotor transformations, we tested whether cells would be activated when a reach is planned to an as-yet unspecified goal. Over one-third of PRR cells increased their firing after an instruction to prepare a reach, but not after an instruction to prepare a saccade, when the target of the movement remained unknown. A partially overlapping population (two-thirds of cells) was activated when the monkey was informed of the target location but not the type of movement to be made. Thus a subset of PRR neurons separately code spatial and effector-specific information, consistent with a role in specifying potential motor responses to particular targets.
Calton
Jeffrey L
JL
Department of Anatomy and Neurobiology, Box 8108, Washington University School of Medicine, 660 S Euclid Ave., St. Louis, Missouri 63110, USA.
Dickinson
Anthony R
AR
Snyder
Lawrence H
LH
D000818:Animals; D002755:Choice Behavior; D003116:Color; D003118:Color Perception / Q000502:physiology; D004594:Electrophysiology; D008253:Macaca mulatta; D008568:Memory / Q000502:physiology; D009043:Motor Activity / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D010296:Parietal Lobe / Q000166:cytology / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time; D012438:Saccades / Q000502:physiology; D013997:Time Factors