Degradation of stimulus selectivity of visual cortical cells in senescent rhesus monkeys.
Human visual function declines with age. Much of this decline is probably mediated by changes in the central visual pathways. We compared the stimulus selectivity of cells in primary visual cortex (striate cortex or V1) in young adult and very old macaque monkeys using single-neuron in vivo electrophysiology. Our results provide evidence for a significant degradation of orientation and direction selectivity in senescent animals. The decreased selectivity of cells in old animals was accompanied by increased responsiveness to all orientations and directions as well as an increase in spontaneous activity. The decreased selectivities and increased excitability of cells in old animals are consistent with an age-related degeneration of intracortical inhibition. The neural changes described here could underlie declines in visual function during senescence.
Schmolesky
M T
MT
Department of Neurobiology & Anatomy, University of Utah School of Medicine, Salt Lake City, Utah 84132, USA.
Wang
Y
Y
Pu
M
M
Leventhal
A G
AG
D000375:Aging / Q000502:physiology*; D000818:Animals; D004594:Electrophysiology; D005260:Female; D006735:Horseradish Peroxidase; D008253:Macaca mulatta; D009410:Nerve Degeneration / Q000503:physiopathology; D009474:Neurons / Q000502:physiology; D009949:Orientation / Q000502:physiology; D014793:Visual Cortex / Q000166:cytology* / Q000503:physiopathology*; D014794:Visual Fields / Q000502:physiology; D014795:Visual Pathways
D006735:Horseradish Peroxidase