Allocation of attention to the eye and mouth region of faces in schizophrenia patients

Abstract

Introduction. The present study examined whether reduced attentiveness to facial features and biased weighting of attention to the eye and mouth region might explain deficits in face processing in schizophrenia. Methods. Healthy controls (n=21) and schizophrenia patients (n=28) from an African Xhosa population were asked to detect target stimuli (dots) superimposed on pictures of faces. General attentiveness to facial features was assessed by measuring overall reaction times to targets superimposed on feature areas of faces and attentiveness to the eye versus mouth region by comparing reaction times to targets on the upper and lower parts of faces. Results. Patients exhibited generally slower target detection speed than comparison subjects but the strength of the attentional bias towards the eyes did not differ between groups (i.e., the reaction time gain for targets in the eye region). A regression analysis indicated, however, that generally slower target detection speed and an attentional bias away from the mouth predicted a deficit in the recognition of open-mouth angry facial expressions in schizophrenia patients. Conclusions. The results give partial support for hypothesis that reduced overall attentiveness to faces and a failure to utilise visual information in salient facial features may underlie affect processing deficits in schizophrenia.