A - 93 How Normal Is Normal? Comparison of “within Normal Limits” Patients in a Memory Clinic with Cognitively Healthy Community Volunteers

Abstract Objective Among patients who present for evaluation at a Memory Disorder Clinic (MDC), a small number are found to have “cognition within normal limits” (WNL). The fact they sought an evaluation suggests WNL may overstate their level of functioning. We compared performance on a brief neurocognitive battery of a recruited sample of healthy older volunteers (HV) to a WNL group from an MDC. Methods 183 HVs with MoCA score ≥ 25 (M age = 75.07, SD = 5.60; 73% female) and 178 (MDC) patients diagnosed WNL (M age = 77.08, SD = 6.62; 53% female) were administered the Shepherd Verbal Learning Test (SVLT; Gifford & Webbe, 2008); the TOMM; a shortened version of the BNT (MACK-SF4); and the Trailmaking Test (TMT-A&B). Results Independent-samples t-tests revealed that HVs had significantly better TMT A & B scores than WNL patients: (M = 33.23, SD = 11.69) vs. (M = 41.19, SD = 15.76), p < 0.001 and (M = 88.98, SD = 35.20) vs. (M = 115.96, SD = 59.61), p < 0.001, respectively. HVs also had significantly better MACK-SF4 scores than WNL (M = 14.31, SD = 1.15) vs. (M = 13.28, SD = 2.27), p < 0.001. No significant group differences were found among SVLT or TOMM scores. WNL was slightly older and less well-educated. Conclusion TOMM scores for both groups were above 47, suggesting good effort. Both HVs and WNL patients performed equally well on all SVLT measures. HVs scored significantly better in Trail-making and confrontational naming, suggesting that in WNL executive function and language might be less than “normal.” These mixed outcomes suggest that WNL performance at a Memory Clinic may still fall short of true normal.