Abstracts

RATIONALE: The nature and significance of self-perception of memory (meta-memory) in epilepsy patients is still a matter of debate. Previous studies which examined the subjective memory complaints and objective memory test performance suggested that memory complaints may be related to depression (Squire L, et al, [italic]Biol Psychiatry[/italic] 1979;14:791-801) or to differences in the degree of self-awareness (Prevey M, et al, [italic]Brain and Cognition[/italic] 1988;7:298-311). The purpose of this study was to systematically explore the differences between self-report versus actual performance on a battery of neuropsychological memory tests in their relation to laterality of seizure focus, depression and anxiety.
METHODS: 22 epilepsy surgical candidates and 10 demographically matched normal controls have been examined. Materials included Visual Analogue Scales as subjective measures of anxiety, depression, verbal and visual memory, a battery of neuropsychological memory tests, Geriatric Depression Inventory and Spielberger Anxiety Scale. ANOVAs were performed on group, anxiety, depression and discrepancy (subjective-objective memory) rescaled z-scores.
RESULTS: Patients with left hemisphere epileptogenic lesions significantly underestimated, while patients with right lesions overestimated their verbal learning and memory abilities as compared to their actual performance on the Rey AVLT, (learning trials 1-5 p=.03; memory after interference trial 7, p=.02; recognition trial p=.05). The same trend has been observed in short-term easy (p=.07) and difficult (p=.04) paired associate learning of WMS. In long-term paired associate learning both patient groups overestimated their abilities. However, the discrepancy score of patients with right lesions was significantly larger than that of patients with left lesions, particularly on the difficult paired associate learning (p=.03). On the visual tests both patient groups overestimated their memory abilities, however, no significant differences were found. Patients with left hemisphere epileptogenic lesions tended to show higher levels of depression and anxiety compared to patients with right hemisphere lesions and normal controls, though, this difference did not reach statistical significance.
CONCLUSIONS: Self-perception of patients with left hemisphere epileptogenic lesions seems to be closer to reality, particularly regarding the adaptively important verbal learning and memory abilities, as compared to self-perception of patients with right hemisphere lesions. This may result in a systematic bias in meta-memory affecting patients[scquote] complaints. In addition, the subjective-objective verbal memory discrepancy score may have a significant predictive value for lateralization of cognitive dysfunction.