Hemispheric lateralization and top-down regulation of the prefrontal cortex on sequential memory of familiar faces.

Abstract

Working memory of familiar faces involves the coordination of multiple brain regions in sensory processing, attention and memory, and relies on robust representations in long-term memory. It is not clear how prior knowledge interacts with bottom-up visual processing at different phases of working memory. In this study, we collected functional magnetic resonance imaging (fMRI) data of 40 right-handed participants during the sequential memory task and recognition task of familiar celebrity faces. We observed strong left-lateralized neural activity in the language-processing areas and right-lateralized activity for visual processing in the dorsal stream. Yet, no obvious hemispheric lateralization was found in either face-selective (fusiform gyrus) or memory-specific (hippocampus) areas. Besides, the left lateralization of prefrontal activity and its task-evoked regulation on visual areas boost face memory performance, i.e., faster reaction and higher accuracy. These findings suggest that the top-down prefrontal regulation plays a critical role in the successful memory of familiar faces. Our study provides neural substrates underlying how familiarity boosts face memory by endorsing prior/common knowledge through left-lateralized language network.