RELATING INDIVIDUAL DIFFERENCES IN FUNCTIONAL CONNECTIVITY TO LEARNING IN RESPONSE TO CENTRAL VISION LOSS - PROJECT SUMMARY EXPECTED TO AFFECT 288 MILLION PEOPLE WORLDWIDE BY 2040, CENTRAL VISION LOSS CAUSED BY MACULAR DEGENERATION IS AN INCREASINGLY PREVALENT VISUAL HEALTH PROBLEM AS THE GLOBAL POPULATION AGES. BECAUSE THESE PATIENTS HAVE LOST THEIR CENTRAL VISION, THEY MUST LEARN TO USE PERIPHERAL VISION TO PERFORM THEIR DAILY ACTIVITIES. THIS ABILITY TO COMPENSATE VARIES FROM PATIENT TO PATIENT, SUCH THAT TWO PATIENTS WITH SIMILAR RETINAL DAMAGE MAY SHOW WIDELY DIFFERENT PERFORMANCE ON COMPLEX VISUAL TASKS. WHILE THIS DIFFERENCE IN COMPENSATION HAS BEEN DIFFICULT TO QUANTIFY, QUANTIFICATION IS A NECESSARY STEP TO UNDERSTANDING THE NEURAL MECHANISMS UNDERLYING COMPENSATORY VISUAL STRATEGIES. TO VALIDATE A MEASURE TO QUANTIFY VISUAL COMPENSATION FOLLOWING CENTRAL VISION LOSS, WE PERFORMED A FACTOR ANALYSIS ON LOW-LEVEL VISION ASSESSMENTS (MEASURING VISUAL ACUITY AND CONTRAST SENSITIVITY) AND HIGH-LEVEL VISION ASSESSMENTS (MEASURING ATTENTION, EPISODIC MEMORY, EMOTION RECOGNITION, AND GENERAL VISUAL FUNCTION) TO IDENTIFY HIGH-LEVEL VISION ASSESSMENTS THAT WERE STATISTICALLY MORE SEPARABLE FROM THE LOW- LEVEL ASSESSMENTS. A LINEAR REGRESSION COMPARED COMPOSITE SCORES OF THE LOW-LEVEL ASSESSMENTS TO THE HIGH- LEVEL ASSESSMENTS. AN INDIVIDUAL PATIENT'S DISTANCE FROM THE REGRESSION LINE REPRESENTS HOW MUCH BETTER (OR WORSE) THEY PERFORMED ON HIGH LEVEL VISION TASKS THAN WAS EXPECTED BASED ON THEIR LOW LEVEL VISION PERFORMANCE. WE REFER TO THIS CONCEPT AS THAT PATIENT'S COMPENSATION. BECAUSE OUR HYPOTHESIS IS THAT THE MECHANISM OF COMPENSATION IS THROUGH CHANGES IN NEURAL CONNECTIONS, INDIVIDUAL DIFFERENCES IN THESE COMPENSATION SCORES WERE COMPARED TO INDIVIDUAL DIFFERENCES IN CORTICAL CONNECTIONS HYPOTHESIZED TO BE IMPORTANT FOR USING PERIPHERAL VISION. USING FMRI RESTING-STATE FUNCTIONAL CONNECTIVITY, WE EXAMINED FUNCTIONAL CONNECTIONS BETWEEN THE FRONTAL EYE FIELDS (FEF), A REGION INVOLVED IN DIRECTING SPATIAL ATTENTION AND SACCADIC EYE MOVEMENTS, TO PARTS OF PRIMARY VISUAL CORTEX REPRESENTING PREFERENTIALLY USED PORTIONS OF THE PERIPHERAL RETINA, NON-PREFERENTIALLY USED PORTIONS OF THE PERIPHERAL RETINA, AND PORTIONS OF THE RETINA AFFECTED BY THE LESION. WE FOUND THAT FEF HAD A RETINOTOPICALLY SPECIFIC RELATIONSHIP TO V1 THAT DEPENDED ON THE LEVEL OF COMPENSATION. THESE RESULTS SUGGEST THAT WE CAN QUANTIFY THE LEVEL OF COMPENSATION IN RESPONSE TO CENTRAL VISION LOSS, AND THAT THESE COMPENSATION SCORES RELATE MEANINGFULLY TO FUNCTIONAL CONNECTIONS. APPLYING THESE SAME APPROACHES TO FUTURE WORK WILL ALLOW INVESTIGATION OF OTHER BEHAVIORAL AND NEURAL MECHANISMS OF COMPENSATION IN RESPONSE TO POOR VISION CAUSED BY CENTRAL VISION LOSS.