Mental state decoding in past major depression: Effect of sad versus happy mood induction

Individuals with mild depression show an enhanced ability to read or “decode” others' mental states. The goal of the present study was to investigate whether this pattern of performance is related specifically to the pathology of depression or whether it is simply a feature of the transient dysphoric state. Forty-one undergraduates with a previous episode of major depression and 52 undergraduates with no depression history participated in a mental state decoding task following a sad versus happy mood induction. Previously depressed participants were significantly more accurate in their mental state judgements than were the never-depressed participants, suggesting that enhanced mental state decoding may be a specific feature of depression in remission. Furthermore, previously depressed participants whose positive mood increased in response to the happy mood induction showed a poorer level of performance on the task, similar to that observed in the never-depressed group. Thus, a happy mood may have induced a somewhat less accurate, but perhaps more adaptive, approach to processing social information. These findings were robust after controlling for current level of depression and anxiety symptoms, intensity of response to the mood induction, response times, and performance on a control task.