Dissociation in awareness of memory and language decline in Alzheimer's disease

OBJECTIVES: The aim of this study was to examine awareness of decline in memory and in language in individuals with Alzheimer's disease (AD), by comparing participant and informant ratings, as well as these ratings and actual test performance. METHODS: We analyzed data from 149 individuals with AD enrolled in the Alzheimer's Disease Neuroimaging Initiative (ADNI) who filled the Everyday Cognition questionnaire and performed memory and language tasks. RESULTS: Participants provided significantly lower assessments of decline than did informants for both memory and language. There was a negative association between informant ratings and memory test scores but no association between participant ratings and memory test scores. Both participant and informant ratings correlated negatively with performance on the language tests. Informant, but not participant, ratings contributed to the prediction of one memory variable beyond demographic factors. Participant ratings contributed to the prediction of language scores beyond demographic factors more than did informant ratings. CONCLUSIONS: The findings reflect better awareness of decline in language than of decline in memory in individuals with AD.