A possible negative influence of depression on the ability to overcome memory interference.

Pattern separation is a mechanism for encoding memories, whereby distinct memory representations are created for very similar stimuli and events. It has been proposed that depression negatively impacts pattern separation abilities. However, a link between depression and performance in memory tasks requiring pattern separation is still unclear even though it is well established that depression is associated with reduced declarative memory performance and decreased hippocampal volume. Accordingly, we designed a study to investigate the relationship between pattern separation performance and the severity of depression symptoms in an otherwise healthy population. Participants completed a pattern separation memory test and a set of questionnaires to gauge their level of depression. We found a negative relationship between depression scores and pattern separation scores. These results provide support for the idea that depression is negatively related to pattern separation performance.