Top-down signal of retrieved information from prefrontal to inferior temporal cortices

We compared neuronal activities in the ventrolateral prefrontal cortex (VLPFC) and the inferior temporal cortex (IT) during the retrieval of an object from the working memory. About one third of IT neurons showed color- and target-selective (CT) or target-selective (T) response during the color cue period of the serial probe reproduction (SPR) task. These object-selective (CT and T) responses in IT could be correlated with the retrieval process of an object from the memorized multiple objects because no objects were presented during this period. However, proportion of CT and T responses was smaller in IT than in VLPFC, where two thirds of neurons showed object-selective response. In addition, object-selective response started earlier in VLPFC than in IT. These results suggest that VLPFC retrieves particular object information from the working memory and sends the retrieved object information to IT. The fact that the responses in the error trials did not decrease in IT suggests that IT is not a critical area for the retrieval process from the working memory.