Scopolamine affects short-term memory but not inferior temporal neurons.

Effects of scopolamine on performance of a delayed matching-to-sample task and on the properties of neurons in anterior-ventral inferior temporal (IT) cortex were examined in two monkeys. Both monkeys were impaired on the task after systemic administration of scopolamine, suggesting that scopolamine disrupts recency memory. Despite the behavioral deficit, neurons in IT cortex, a region having an important role in visual memory and neuronal properties consistent with that role, were largely unaffected by scopolamine. This dissociation between the behavioral and neuronal effects of scopolamine indicates that the drug either acts at a different site or disrupts unobserved mechanisms at the IT site.