Self-reported awareness of performance in dementia.

The purpose of this study was to test the theory that patients with dementia do not update their self-perceptions based on actual performance. This experiment compared differences between post-task perceptions of performance and actual performance in persons with dementia and normal controls on seven cognitive tasks. Participants included 35 volunteers (12 with dementia and 23 without) from the Houston Veterans Affairs nursing home and geropsychiatric inpatient unit and outpatient clinics and from the Baylor College of Medicine's Alzheimer's Disease Center. Measurements included 7 subtests of the Alzheimer Disease Assessment Scale-Cognitive Subscale and standardized interview questions assessing perceived performance on each of these subtests. Participants with dementia had similar perceptions of performance to normal controls yet evidenced much worse performance on all seven cognitive screening tasks. Thirty-one percent of normal controls over-estimated their performance, compared to 64% of those with mild-moderate dementia and 93% with moderate-severe dementia. Our study supports the theory that demented individuals do not update their self-perceptions of performance. However, a large portion of normal controls was also inaccurate evaluating their own performances. Thus, post-diction measures provide useful insight into the mechanisms of self-awareness but may not be appropriate assessment tools to identify clinically significant impaired self-awareness.