Project Grant F31AG101919

MULTISENSORY INTEGRATION IN AGING AND COGNITIVE DECLINE - ABSTRACT THE AGING PROPORTION OF THE POPULATION IS PROJECTED TO INCREASE DRAMATICALLY IN THE COMING DECADES DUE TO ADVANCES IN MEDICAL CARE. EVEN IN NORMAL HEALTHY AGING THERE IS A DECLINE IN SENSORY FUNCTION; HOWEVER, THIS DECLINE IS MORE PRONOUNCED IN INDIVIDUALS WITH ALZHEIMER'S DISEASE OR OTHER DEMENTIAS. IMPAIRMENTS IN SENSORY FUNCTION ARE IMPORTANT TO IDENTIFY AND TRACK IN THESE CLINICAL POPULATIONS, AS EVIDENCE SUGGESTS THAT THEY MAY BE PREDICTIVE OF AND EVEN CONTRIBUTE CAUSALLY TO THE PROGRESSION OF COGNITIVE DECLINE. HOWEVER, MOST STUDIES HAVE FOCUSED ON THE RELATIONSHIPS BETWEEN COGNITIVE DECLINE AND THE COMPETENCY OF THE INDIVIDUAL SENSES STUDIED IN ISOLATION. THE RELATIONSHIP BETWEEN COGNITIVE DECLINE AND THE ABILITY TO INTEGRATE INFORMATION ACROSS DIFFERENT SENSES ("MULTISENSORY INTEGRATION"), WHICH IS FUNDAMENTAL TO INTERPRETING AND REACTING TO ENVIRONMENTAL EVENTS, IS UNDEREXPLORED. AS A HIGHER-ORDER PROCESS THAT REQUIRES SIGNAL COORDINATION ACROSS LONG NEURAL DISTANCES, MULTISENSORY INTEGRATION IS LIKELY TO BE COMPROMISED IN COGNITIVE DECLINE, AS IT IS IN OTHER CLINICAL CONDITIONS (E.G., AUTISM AND SCHIZOPHRENIA). ONE OF THE REASONS THAT IT HAS NOT BEEN WELL-CHARACTERIZED IN THIS CLINICAL POPULATION IS A LACK OF ACCESSIBLE TOOLS FOR ITS ROBUST ASSESSMENT. THE PRESENT PROPOSAL SEEKS TO FILL THIS GAP BY VALIDATING (AIM I) AND DEPLOYING (AIM II) A SUITE OF PSYCHOMETRIC TOOLS APPROPRIATE TO ASSESS MULTISENSORY INTEGRATION IN INDIVIDUALS WITH MILD/MODERATE COGNITIVE IMPAIRMENT. THE SUITE WILL ROBUSTLY MEASURE MULTISENSORY INTEGRATION IN TWO ECOLOGICALLY VALID CONTEXTS THAT BRACKET A RANGE OF COMPLEXITY, FROM LOW (DETECTION/LOCALIZATION) TO HIGH (SPEECH PERCEPTION). IMPORTANTLY, THE TOOLS FIRST MEASURE AND THEN CONTROL FOR VARIATIONS IN THE SENSITIVITY OF THE INDIVIDUAL SENSES, WHICH OUR PRELIMINARY DATA SHOW IS ESSENTIAL TO THE TARGETED AND ROBUST ASSESSMENT OF MULTISENSORY INTEGRATION. IN AIM I, THE TESTING SUITE WILL BE USED TO COLLECT DATA FROM HEALTHY COGNITIVELY-NORMAL (MOCA > 26) INDIVIDUALS ACROSS THE ADULT AGE RANGE TO ESTABLISH NORMATIVE (CONTROL) PERFORMANCE STANDARDS. WE EXPECT MULTISENSORY PERFORMANCE TO BE SIGNIFICANTLY ELEVATED ABOVE UNISENSORY PERFORMANCE AT ALL AGES. IN AIM II, THE SUITE WILL BE USED TO ASSESS MULTISENSORY INTEGRATION IN A CLINICAL POPULATION WITH DIAGNOSED MILD/MODERATE COGNITIVE IMPAIRMENT (15