Activating memories of depression alters the experience of voluntary action.

The sense of agency is a profoundly important human experience and is strongly linked to volitional action. The importance of this experience is underscored by the fact that many neurological and psychiatric disorders are partially characterized by an abnormal sense of agency (e.g., schizophrenia, anxiety disorders, depression). Healthy participants perceive the temporal interval between a voluntary action and its effect to be shorter than it actually is, and this illusion has been suggested as an implicit index of agency. Here, we investigated whether activating memories of depression alters perception of this action-effect interval, compared to activating memories of the previous day, or a baseline condition in which specific memories were not activated. Results showed that action-effect interval estimates were significantly longer after remembering a depressing episode than after remembering the previous day, or in the baseline condition. Thus, activating memories of depression alters the experience of voluntary actions and effects. We suggest that interval estimation measures could be useful in clinical settings, to implicitly assess the sense of agency in patients with disorders affecting their sense of control. In this way, obtaining action-effect interval estimates, pre-, during, and post-treatment, could aid in tracking treatment-induced changes in the sense of agency.