Subjective memory complaints in patients with epilepsy: The role of depression, psychological distress, and attentional functions

While objective memory dysfunctions have been thoroughly investigated in patients with epilepsy, assessment of subjective memory complaints (SMC) remains challenging. Former studies have demonstrated an impact of patients' depressive mood on SMC. However, the impact of more general psychological distress and cognitive functioning in non-memory domains on SMC has only received little attention so far. We therefore sought to determine the factors which may particularly predict SMC in a sample of patients with focal epilepsy (n=99) who accomplished (1) a comprehensive neuropsychological assessment, (2) a subjective memory questionnaire, and (3) scales of self-rated depressive mood and psychological distress. General psychological distress (as measured by the Symptom Checklist- 90-Revised) accounted for a high proportion of SMC and, critically, explained more variance than depressive mood as a single factor (as measured by the Beck Depression Inventory II). Furthermore, SMC were predicted by recall measures of a verbal serial learning task, but also by measures of attention, importantly. Hence, our data firstly indicate that beyond the impact of depressive mood, SMC may be more accurately explained by psychological distress in a more general sense. Secondly, our study provides evidence that patients' estimation of subjective memory is not solely based on functioning in memory domains. Attentional resources may also be critical for patients' perception of everyday memory functioning.