Mood as input and rumination

Rumination has been recognised as an important maintaining factor in depression. Adapting the mood-as-input theory to rumination, we hypothesised that high ruminators have a default “as many as can” stop rule for determining when to stop analysing the causes and consequences of any problem, such that negative mood signals insufficient problem solving, leading to recurrent analysis and self-focus (i.e. rumination). To explore this hypothesis, 60 participants were randomly instructed to continue generating reasons for a recent depressed mood under three conditions: an “as many as you can” stop-rule, an “as long as you feel like continuing” stop-rule, and a “no stop-rule” condition. Participants were split into high and low ruminators on a median split on Ruminative Response Scale scores. As predicted, the high ruminators in the “as many as you can” and “no stop rule” conditions produced significantly more reasons for their depressed mood (without significantly differing from each other), than either the high ruminators in the “feel like continuing” condition or the low ruminators in all conditions. These results suggest that high ruminators adopt a default “as many as can” stop rule and that teaching high ruminators to use a “feel like continuing” rule may reduce rumination.