Reaching in the dark: enhanced responses in posterior parietal cortex.
In order to assess the relative importance of visual input to area 7 reach-related neuronal activity, a monkey was trained to reach to visual targets displayed on a video-monitor, both with and without visual feedback. Visual feedback was removed by having the monkey reach in darkness to a previously illuminated target. Of 19 reach-related cells recorded in area 7 both in the light and the dark, ten showed an enhancement of discharge in the dark. These included area 7b cells sensitive to screen contact and area 7a cells active during reach. Dark enhancement of active somatic responsiveness may partially compensate for the loss of visual guidance.
MacKay
W A
WA
Department of Physiology, University of Toronto, Canada.
Mendonça
A J
AJ
Blum
B
B
D000818:Animals; D003624:Darkness; D005246:Feedback; D008252:Macaca fascicularis; D008839:Microelectrodes; D009068:Movement / Q000502:physiology*; D010296:Parietal Lobe / Q000502:physiology*; D014796:Visual Perception