Maladaptive Processing of Maladaptive Content: Rumination as a Mechanism Linking Cognitive Biases to Depressive Symptoms.

Cognitive theories propose that negatively biased thinking is an important factor in the development and maintenance of depression. The mechanisms by which cognitive biases lead to depression, however, have not been thoroughly researched. One potential mechanism is that negatively biased thoughts trigger rumination, or the process of focusing passively and repetitively on the causes and consequences of one's mood, a well-established risk factor for depression. In a series of three studies, we examined rumination and other cognitive emotion regulatory strategies as mechanisms of the relationship between cognitive biases and depressive symptoms. We found consistent evidence that rumination mediates the relationship between interpretation and memory biases and depressive symptoms. The indirect effects through rumination were stronger than indirect effects through other cognitive emotion regulation strategies (dampening and worry). These findings indicate that negatively biased thinking may increase risk for depression by increasing rumination, supporting the notion that rumination is a useful target for intervention with depressed clients.