Self-awareness of cognitive efficiency: Differences between healthy elderly and patients with mild cognitive impairment (MCI)

Introduction: Self-estimation of performance implies the ability to understand one's own performance with relatively objective terms. Up to date, few studies have addressed this topic in mild cognitive impairment (MCI) patients. The aim of the present study was to compare objective measures of performance with subjective perception of specific performance on cognitive tests and investigate differences in assessment between MCI patients and healthy elderly. Method: Thirty-five participants diagnosed with MCI (women = 16, men = 19, mean age = 65.09 years +/- SD = 7.81, mean education = 12.83 years +/- SD = 4.32) and 35 control subjects similar in terms of age and education (women = 20, men = 15, mean age = 62.46 years +/- SD = 9.35, mean education = 14.26 +/- SD = 2.84) were examined with an extended battery of neuropsychological tests. After every test they were asked to self-evaluate their performance by comparing it to what they considered as average for people of their age and educational level. This self-evaluation was reported on a scale ranging from -100 to +100. Results: Significant differences were found in the self-assessment patterns of the two groups in memory measures of verbal and visual delayed recall, visuospatial perception, and tests of attention. MCI patients overestimated their performance on every cognitive domain while control participants underestimated their performance on measures of verbal memory. Conclusions: The present results indicate that accuracy of self-report is not uniform across groups and functional areas. The discrepancies in the MCI patients indicate unawareness of their memory deficits, which is contradictory to subjective memory complaints as being an important component for clinical diagnosis.