Enhancement of object representations in primate perirhinal cortex during a visual working-memory task.
We compared single-cell activities in perirhinal cortex (PRh) as well as adjacent visual cortex (area TE) across two tasks. One task required the monkey to identify any stimulus repetition within a sequence of object stimuli. In the other task, the same stimuli were presented, but the monkey didn't have to remember them. PRh responses during the object-memory task were elevated relative to those during the second task. In TE, on the other hand, there were no significant task-related differences in responses. We did not observe task-related differences related to repetition effects in either brain area. The onset of the enhanced signal in PRh during the object-memory task occurred with a latency of 80 ms after the onset of the stimulus response, suggesting that it was the result of top-down feedback.
Lehky
Sidney R
SR
Computational Neuroscience Lab, The Salk Institute, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA. sidney@salk.edu
Tanaka
Keiji
K
D000818:Animals; D001288:Attention / Q000502:physiology; D002540:Cerebral Cortex / Q000502:physiology*; D003463:Cues; D003627:Data Interpretation, Statistical; D004567:Electrodes, Implanted; D004594:Electrophysiology; D005246:Feedback / Q000502:physiology; D005260:Female; D008251:Macaca; D008570:Memory, Short-Term / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D010775:Photic Stimulation; D017397:Prefrontal Cortex / Q000166:cytology / Q000502:physiology; D021641:Recognition, Psychology / Q000502:physiology; D013238:Stereotaxic Techniques; D014793:Visual Cortex / Q000166:cytology / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*