The Relationship between Rumination and Autobiographical Memory Specificity in People with Depression

Rumination and autobiographical memory specificity are neurocognitive factors associated with the course of a major depressive disorder (MDD). Yet, their relationships have not been fully understood. In this study, we explored whether a rumination of different valences had varying effects on autobiographical memory specificity in participants with major depressive disorder. We used a 2 (group: MDD, control) x 2 (rumination: positive, negative) x 2 (time: pre, post) mixed design. Fifty-two currently depressed people and 52 non-psychiatric controls completed this experiment. They completed the Autobiographical Memory Test and the mood ratings before and after completing either the positive or the negative rumination task. In the rumination task, they were requested to focus their attention on some specific thoughts about themselves. Results showed a significant group (depressed, control) x time (pre, post) interaction effect for the number of specific memories. This was a result of a significant decrease in specific memories retrieved after negative rumination in the depressed group but not after positive rumination. No significant differences among the non-psychiatric controls were observed. Our findings suggest that possible inhibitory deficit in people with depression may have compromised the ability to shunt task-irrelevant negative materials from working memory. The overloading of the working memory may be associated with reduced retrieval of specific memories.