Project Grant F31MH146175

FUNCTIONALLY SPECIALIZED TEMPORAL AND FRONTAL LOBE REGIONS FOR IDENTITY RECOGNITION AND UPDATING - PROJECT SUMMARY A CENTRAL QUESTION IN SOCIAL BEHAVIOR RESEARCH IS HOW INDIVIDUAL IDENTITIES ARE RECOGNIZED AND UPDATED AS FEATURES CHANGE OVER TIME. DIFFICULTIES WITH IDENTITY RECOGNITION AND THEIR SOCIAL CONSEQUENCES CAN LEAD TO SOCIAL WITHDRAWAL, WHICH MAY WORSEN OTHER CONDITIONS. IDENTITY RECOGNITION IS IMPAIRED IN INDIVIDUALS WITH NEUROPSYCHIATRIC AND NEURODEGENERATIVE DISORDERS LIKE ALZHEIMER'S DISEASE (AD) AND AUTISM SPECTRUM DISORDER (ASD), CAUSING SIGNIFICANT DISRUPTIONS IN DAILY LIFE. THE DORSOLATERAL PREFRONTAL CORTEX (DLPFC) IS KNOWN TO SUPPORT HIGH-LEVEL COGNITIVE TASKS, INCLUDING PROCESSING TARGET IDENTITY, UNCERTAINTY, AND SOCIAL PREDICTION. CONVERSELY, THE SUPERIOR TEMPORAL SULCUS (STS) PROCESSES CONSPECIFIC IDENTITY AND FEATURES. IN THIS PROPOSAL, WE WILL INVESTIGATE HOW NEURONAL ACTIVITY IN DLPFC AND STS SHIFTS TO ADAPT TO IDENTITY UPDATING AND HOW THE PROJECTION FROM STS TO DLPFC (STSDLPFC) FACILITATES THIS PROCESS. FACES AND VOICES ARE THE MOST CRUCIAL ASPECTS OF CONSPECIFIC IDENTITY, WITH HUMANS AND NONHUMAN PRIMATES EVOLVING HIGH VARIABILITY IN THESE FEATURES TO AID RECOGNITION. IN AIM 1, TO STUDY IDENTITY RECOGNITION AND UPDATING BEHAVIOR, I WILL TRAIN MARMOSET MONKEYS ON A NOVEL FACE-VOICE MATCHING TASK THAT TEACHES THEM TO RECOGNIZE SEVERAL CONSPECIFIC IDENTITIES FROM VIDEOS OF VOCALIZING INDIVIDUALS. AFTER LEARNING AN IDENTITY, WE WILL ALTER A FACIAL FEATURE'S COLOR OR SHAPE WHILE KEEPING THE VOICE UNCHANGED, ANCHORING IDENTITY THROUGH VOICE RECOGNITION AND REQUIRING SUBJECTS TO "UPDATE" THEIR FACIAL REPRESENTATION. I WILL FUNCTIONALLY LOCALIZE THE ACTIVE DLPFC AND STS DURING THE UPDATING PROCESS USING FDG-PET SCANS, AND IMPLANT MULTIELECTRODE ARRAYS INTO DLPFC AND STS TO RECORD NEURAL ACTIVITY DURING IDENTITY RECOGNITION AND UPDATING. I PREDICT THAT POPULATION ACTIVITY PATTERNS IN DLPFC WILL INITIALLY DIFFER FOR THE ALTERED FEATURES BUT WILL EVENTUALLY CONVERGE TO THE LEARNED IDENTITY AFTER UPDATING, PARALLELING BEHAVIORAL PERFORMANCE. ADDITIONALLY, I EXPECT STS ACTIVITY TO PREDICT DLPFC ACTIVITY, ESTABLISHING A CAUSAL RELATIONSHIP, ALTHOUGH ACTIVITY IN STS RELATED TO ALTERED FEATURES WILL REMAIN DISTINCT FROM THE LEARNED IDENTITY AFTER UPDATING. IN AIM 2, I WILL EXAMINE THE NECESSITY OF THE STSDLPFC PROJECTION FOR IDENTITY UPDATING. USING CHEMOGENETIC APPROACHES WITH NOVEL VIRAL VECTORS, I WILL ASSESS HOW INHIBITION OF STSDLPFC AFFECTS BEHAVIORAL UPDATING PERFORMANCE. I PREDICT THAT INACTIVATING STSDLPFC DURING UPDATING, BUT NOT RECOGNITION, WILL DECREASE PERFORMANCE ACCURACY AND INCREASE RESPONSE LATENCY. THE INSIGHTS FROM THESE EXPERIMENTS WILL PROVIDE A NEW FRAMEWORK FOR UNDERSTANDING NEURAL CIRCUITS INVOLVED IN IDENTITY PROCESSING, WHICH COULD INFORM HOW THESE CIRCUITS BREAK DOWN IN NEURODEGENERATIVE AND NEUROPSYCHIATRIC DISORDERS SUCH AS AD AND ASD. THIS WORK WILL BE CONDUCTED AT THE UNIVERSITY OF PITTSBURGH, WHERE I WILL BE SUPPORTED BY MENTORS WHO WILL TRAIN ME IN SCIENTIFIC CONCEPTS, TECHNIQUES, AND PROFESSIONALISM. MY TRAINING WILL ENCOMPASS BEHAVIORAL, NEUROIMAGING, CHEMOGENETIC, NEUROPHYSIOLOGICAL, AND COMPUTATIONAL METHODS TO ADVANCE OUR UNDERSTANDING OF IDENTITY PROCESSING. DEVELOPING THESE SKILLS IS ESSENTIAL FOR MY GOAL OF BECOMING AN INDEPENDENT NEUROSCIENTIST SPECIALIZING IN IDENTITY PROCESSING AND MULTISENSORY INTEGRATION.