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Time perception has long been known to be impaired in schizophrenia. Moreover, recent neuropsychological theories have postulated abnormalities of cognitive motor control in schizophrenia. However, the intersection of these two topics has rarely been studied, and it is unclear what role subjects' own actions may play in the construction of subjective time representation. The present experiment compared the performance of 19 patients with schizophrenia and 24 normal controls in a timing judgment task. The results show that patients bind two consecutive movements more strongly than controls. This anomaly could play a role in the subjective pathological experiences of patients.

An abnormal sense of agency is among the most characteristic yet perplexing positive symptoms of schizophrenia. Schizophrenics may either attribute the consequences of their own actions to the intentions of others (delusions of influence), or may perceive themselves as causing events which they do not in fact control (megalomania). Previous reports have often described inaccurate agency judgements in schizophrenia, but have not identified the disordered neural mechanisms or psychological processes underlying these judgements. We report the perceived time of a voluntary action and its consequence in eight schizophrenic patients and matched controls. The patients showed an unusually strong binding effect between actions and consequences. Specifically, the temporal interval between action and consequence appeared shorter for patients than for controls. Patients may overassociate their actions with subsequent events, experiencing their actions as having unusual causal efficacy. Disorders of agency may reflect an underlying abnormality in the experience of voluntary action.