A ticking clock for the production of sequential actions: Where does the problem lie in schizophrenia?

Schizophrenia has been associated to a distorted time clock. By subtracting contact duration from Inter Response Interval, we report evidence for preserved internal clock in schizophrenia, with normal spontaneous tapping tempo. Contact durations were however increased in patients suggesting a specific problem in the fast integration of incoming haptic feedback with outgoing motor efferences. This integration deficit would emerge at an early phase, since Ultra High Risk patients also revealed abnormal tapping stability. Tactile screens revealed to be a simple and low cost apparatus that may constitute a suitable measuring kit for the characterisation of sensory motor deficits in clinical settings.