Anhedonia and emotional word memory in patients with depression

Anhedonia is a key diagnostic criterion for major depression. Investigating the relation between the specific symptoms and emotional processing may help to understand the underlying cognitive mechanism of anhedonia in depression. In this study, we explored the potential association between memory for emotional words and anhedonia in 71 patients with depression and 61 healthy individuals. An emotional word-rating task was administered to assess self-reported emotional experience to words on both valence and arousal dimensions, and subsequent recall and recognition memory for these words. Depressed patients demonstrated a reduction in pleasure and arousal experience to positive words, but an increase in arousal experience to negative words. Depressed patients also displayed a lower overall memory performance in recall measure and a bias to memory of more negative words. Moreover, state anhedonia and trait anhedonia were associated with attenuated positive experience and enhanced negative experience in patients with depression only. Higher levels of anhedonia and depression severity were also associated with fewer positive words and more negative words memory. Patients with depression displayed a flat pattern of emotional experience to positive stimuli and a tendency towards rating negative stimuli more intensely.