Bilateral ECT and autobiographical memory of subjective experiences related to melancholia: a pilot study

The aim of this pilot study was to systematically assess the influence of bilateral, sine wave ECT on autobiographical memory of past subjective experiences related to melancholia. Twenty-one inpatients who met DSM-III-R criteria for a Major Depressive Episode, Melancholic Type, were included in the study. Twelve patients were treated by ECT (12 treatments), antidepressants and benzodiazepines; the comparison group comprised 9 patients treated by antidepressants and benzodiazepines. The Structured Interview Guide for the HDRS (SIGH-D) was used at admission and after the ECT treatment to standardize data collection about subjective experiences related to the depressive episode. Memory of subjective experiences related to melancholia was assessed with free-recall, cued-recall and recognition tasks. In addition, a free recall of events of the day on which the patients came to the hospital for their treatment was administered. These tasks were administered 1 week after the last treatment in the ECT-treated group and 4 to 6 weeks after the beginning of the treatment in the comparison group. Free-recall, cued-recall and recognition performances were significantly lower in the ECT-treated group than in the comparison group. No significant correlation was found between memory of events related to hospital admission and memory of subjective experiences related to depression. In conclusion, bilateral, sine wave ECT impairs autobiographical memory of subjective experiences related to melancholia in subjects tested 1 week after completion of a course of ECT.