Short-Term Memory Trace in Rapidly Adapting Synapses of Inferior Temporal Cortex

Yasuko Sugase-Miyamoto, Zheng Liu, Barry J. Richmond (National Institutes of Health USA), Matthew C. Wiener (Merck Research Laboratories), Lance M. Optican (National Institutes of Health)

To know whether one is looking at an object seen a few seconds ago or not depends on visual short-term memory. The scalar matched filter model used for the data analysis has no parameters. Three noise parameters were fit to the data using the simplex algorithm in modeFRONTIER. Visual short-term memory tasks depend upon both the inferior temporal cortex (ITC) and the prefrontal cortex (PFC). Activity in some neurons persists after the first (sample) stimulus is shown. To study short-term memory, we recorded single neuronal activity from two brain areas of monkeys, the TE and the perirhinal cortex of the temporal lobe, known to be important in visual pattern recognition and memory. This delay-period activity has been proposed as an important mechanism for working memory. In ITC neurons, intervening (non-matching) stimuli wipe out the delay-period activity; hence, the role of ITC in memory must depend upon a different mechanism.