Word recognition memory before and after successful treatment of depression.

One of the most frequent and neuropsychologically well investigated symptoms in depression is reduced memory capacity. In this study, we investigated the course of disease in 16 patients with moderate depression and Borna disease virus (BDV) infection. Recently, it could be shown that BDV infection might play an important role in the etiology of subtypes of depression. Amantadine treatment was used as an antidepressant and antiviral compound. In order to assess memory capacity, event-related potentials (ERPs) were evaluated in ten of sixteen patients in a continuous word recognition experiment using a series of emotionally neutral, positive or negative words. During the treatment period the patients' clinical condition improved significantly. ERPs showed a reduced old/new effect before and after treatment independent of the words' emotional content. These findings suggest a reduced memory capacity being relatively independent of clinical outcome and ability to use emotional connotations for memory mechanisms. However, a significant positive shift over frontal electrodes did occur, which was concomitant with the improvement of depression, suggesting evidence for changed frontal cortical activity.