Rumination alters working memory and effort perception

Background:Objective and subjective cognitive deficits, particularly in working memory (WM), arecommon in psychiatric conditions, yet their mechanisms remain poorly understood.Rumination, a key transdiagnostic factor, has been proposed to contribute to thesedeficits by depleting executive resources. However, the causal impact of ruminativestates on cognitive performance and subjective difficulties remains untested.Methods:In a preregistered online study, 282 participants were randomly assigned to a ruminationor neutral group. Both groups recalled an upsetting event, followed by a ruminationinduction or neutral condition for either group. WM was assessed using an n-back task,while subjective difficulties were assessed through effort rating. These were administeredbefore and after induction. Mixed ANOVAs were employed to assess the induction effects.Results:There was a significant group × time interaction for performance and effort perception(independently from performance). These effects were not moderated by trait ruminationor depressive symptom severity. Performance effects were mediated by increased self-report cognitive interference, while perceived effort was not. Post hoc analyses revealedthat rumination selectively affected performance in non-match trials and did not interactwith cognitive load (n-level).Conclusion:Even brief episodes of ruminative states can alter both cognitive performance and thesubjective experience of it. Cognitive interference mediating performance but not effortsuggests distinct underlying mechanisms. The selective effect on non-match trialswithout an effect of cognitive load points to disrupted inhibitory control. Together,targeting rumination may not only alleviate psychological symptoms but also helppreserve cognitive functioning.