The integration of facial gestures and vocal signals is an essential process in communication and relies on an interconnected circuit of brain regions. The neural basis of face and vocal integration is a topic of great importance since sensory integration is essential to speech perception and object recognition and is impaired in autism spectrum disorders (ASD) and other intellectual disabilities. Our previous investigations have shown that primate VLPFC, a proposed homologue of human IFG, has neurons that are responsive to species-specific faces and that it integrates these stimuli. Furthermore, VLPFC neurons are active during a crossmodal working memory task with neurons demonstrating increased delay activity, match suppression & enhancement, and activity that is tied to both task and stimulus factors. Importantly, VLPFC neuronal activity is also critical for audiovisual working memory since temporary inactivation results in a decrease in working memory performance. In this proposal we will focus on the role of two additional cortical areas that are connected to VLPFC. Both the dorsolateral prefrontal cortex (DLPFC) and the medial prefrontal cortex (MPFC) are connected to VLPFC and have been shown to support cognitive functions that are a part of audiovisual working memory. Furthermore, we will address the lingering question of which features of face and vocal stimuli are integrated by VLPFC neurons during audiovisual processing and we will expand our focus to ensembles of VLPFC neurons in order to appropriately address this in Aim 3. We hypothesize that the connected cortical areas VLPFC, DLPFC and MPFC play different but contributing roles in the processing, integration and remembering of face and vocal information during social communication.
The ventrolateral prefrontal cortex is part of brain network involved in social communication. It is important for the processing, integration and remembering of face and vocal information. This proposal is aimed at expanding our understanding of the cortical network that underlies audiovisual memory to include investigations of dorsolateral and medial prefrontal regions in addition to the ventrolateral prefrontal cortex. Our questions are aimed at understanding how neurons in these areas process and integrate communication stimuli. These questions are important since individuals with Autism Spectrum Disorder show deficits in audiovisual speech perception which may originate from disruption of the integration of auditory and visual information which would have a deleterious effect on speech perception and social communication.
Showing the most recent 10 out of 15 publications
