Separating component processes of theory of mind in schizophrenia

Objective. It has been argued that in order to take the perspective of another the 'default' self-perspective must first be inhibited. Thus, executive function failures (and specifically, reduced inhibitory control of the self-perspective) may contribute to the theory of mind (ToM) difficulties that have been observed in schizophrenia. Method. Participants with schizophrenia (N = 28) and demographically matched controls (N = 30) were administered a behavioural measure of ToM that directly manipulates inhibitory demands by involving either high- or low-levels of self-perspective inhibition. Results. Relative to controls, participants with schizophrenia demonstrated impaired ToM, but did not have particular difficulty on the task that placed high demands on self-perspective inhibition. Conclusion. Disruption of other-perspective taking, rather than self-perspective inhibition, appears to be the more important determinant of ToM impairment in schizophrenia. This finding is discussed in relation to competing perspectives of ToM.