ASSESSING SYMPTOMS OF COGNITIVE AND LINGUISTIC DECLINE IN PRODROMAL ALZHEIMER’S DISEASE: A NEW STUDY OF MILD COGNITIVE IMPAIRMENT

Current clinical diagnostics of cognitive impairments potentially leading to AD focus primarily on memory, supplemented by assessments of executive functioning and visuospatial processing. Recent research provides evidence that other cognitive domains, especially language, also may reveal early indicators of prodromal AD. However, the relationship between language and cognitive deficits in this prodromal group has not been explored. Through interdisciplinary, cross-institutional collaboration, we compare results from a new study of an MCI population (N=21) to a matched Healthy Aging (HA) (N=21 and a Healthy Young Adult (HY) (N=10) population on a new series of linguistic tests (complex sentence production) as well as on a clinically established multi-domain cognitive screen (ACE-R). We compare and contrast results across these various neuropsychological cognitive and linguistic results to provide a profile of which deficits do and do not differentiate MCI from HA across this extended cognitive-linguistic testing. Subjects in the three groups differed in total ACE-R score and on our novel linguistic tasks. However, total ACE-R score significantly predicts performance on linguistic tasks only in the HA (T 2.46, df 41, p .02) and not in HY or MCI. Similarly, performance on the ACE-R naming task predicted performance on linguistic measures for HA, not for MCI or HY. Overall cognitive functioning, as measured by screening measures such as the ACE-R does not appear to predict language function in MCI. This suggests that difficulties with language functioning in MCI may be independent of more general cognitive deficits. This in turn suggests that language and cognition may be dissociated in MCI more than in healthy aging or young.