Using Expressive Writing to Test an Evolutionary Hypothesis About Depressive Rumination: Sadness Coincides with Causal Analysis of a Personal Problem, Not Problem-solving Analysis

The analytical rumination hypothesis proposes that depression is an evolved response to complicated life stressors or problems. As part of this response, depressive symptoms promote analytical rumination, a prolonged and distraction-resistant style of thinking that functions to address the triggering problem. Analytical rumination involves analytical thinking about why the problem happened (i.e., causal analysis) and how it can be solved or alleviated (i.e., problem-solving analysis). Previous research analyzing cross-sectional data suggests that causal analysis is directly related to depressive symptoms and precedes problem-solving analysis, but this finding should be supported with experimental methods. We used an expressive writing paradigm to investigate the temporal order of the emotional symptoms of depression, causal analysis, and problem-solving analysis in a non-clinical sample. In two studies, we randomized participants to write about their personal problems or a neutral topic (i.e., control writing). All participants reported on their emotions during writing, and they retrospectively reported on their thoughts after writing. Consistent with our predictions, expressive writing reliably increased self-reported sadness and causal analysis but not problem-solving analysis. Linguistic analyses partially supported our predictions. Relative to control writing, expressive writing contained more words related to causal thoughts and problem-solving. Since causal analysis and sadness increased over the short time frame of the writing intervention, while problem-solving analysis was unaffected, the results support our prediction that causal analysis precedes problem-solving analysis. We discuss the limitations of our studies, as well as EW’s utility for studying the analytical rumination hypothesis.