Effect of expressional chimeric faces on the attentional bias in neglect patients

Abstract

Objective To investigate the effect of expressional chimeric faces on the attentional bias in unilateral spatial neglect (USN) patients. Methods 12 USN patients and 30 matched healthy controls (HC) were involved in this study. All of them were performed with happy-neutral and sad-neutral expressional chimeric faces (ECF) and the attentional deviation scores were compared between and within groups. Results There were statistically significant differences of attentional deviation scores (happy-neutral ECF: t=15.550, P<0.01; sad-neutral ECF: t=12.192, P<0.01) between the USN group (happy-neutral ECF: 0.78±0.22; sad-neutral ECF: 0.50±0.20) and the HC group (happy-neutral ECF: -0.31±0.20; sad-neutral ECF: -0.25±0.17), with rightward bias in the USN group and small leftward bias in the HC group. For the USN group, the magnitude of rightward bias in the sad-neutral ECF condition was reduced than in the happy-neutral ECF condition (t=3.954, P=0.002). There were no statistically differences under happy-and sad-neutral ECF conditions within the HC group (t=-1.302, P=0.203). Conclusions USN patients show rightward attentional bias under both happy-and sad-neutral ECF conditions. However, the magnitude of rightward bias under the sad-neutral ECF condition are reduced significantly. This might be attributed to the unconscious processing of stimuli in the neglected side and emotion cognition of the brain hemispheres. Key words: Emotions; Attention; Cognition disorder; Neuropsychology