Dysfunction of encoding of emotionally negative information in depressive disorders

At the present time, the phenomenon of overgeneral memories in depressive disorders induces considerable research interest and consists in actualization difficulties of specific details of negative events. Theoretical interpretations with regard to this phenomenon concentrate on possible dysfunctions of information retrieval process and suppose a relative safety of encoding and consolidation of information. In order to test this hypothesis the present research was carried out. 19 healthy controls and 20 patients with depression participated in this study. They were presented with video clips of positive, negative and neutral social situations. Immediately after demonstration participants had to recognize visual details of perceived material, which demonstrated among visually and semantically similar “noise” fragments. We analyzed the amount of successful recognition, type of mistakes and eye movements characteristics of participants during perception of video clips and recognition of fragments. There are no significant differences between depressive patients and healthy controls regarding parameters of eye movements in the perception of positive and neutral video clips. Analysis of successfully recognition, committed mistakes and eye movements in recognition of fragments show patients with depressive disorders, in contrast to healthy subjects, demonstrate dysfunctions of formation of specific details representation in short-term memory regarding the negative social situations, but they may understand semantic content of these situations. At the same time, patients don’t differ from healthy individuals in the characteristics of fragments recognition of positive and neutral events. The results need a further verification and elaboration. Nonetheless, the results suggest that dysfunctions of encoding of affectively meaningful information may be a basic of overgeneral memories phenomenon in depressive disorders.