Ambiguous handedness and visuospatial pseudoneglect in schizotypy in physical and computer-generated virtual environments

Virtual reality (VR) technology has increased clinical attention in the health care of schizophrenia spectrum disorders in both diagnoses of the symptoms and assessment of schizotypal traits. However, the exact nature of VR-induced positive treatment effect in schizotypy is still unknown. In this study, VR technology was used as a non-invasive neurocognitive trigger to test the asymmetric visuospatial representational instability found in individuals with high schizotypy. The study aimed to reveal the brain functional hemispheric laterality in physical and virtual realities in individuals with schizotypal traits. Fifty-one healthy, right-handed participants (24 males and 27 females) were enrolled through public advertisements. Hemispheric functional asymmetry was measured by the Line Bisection Task (LBT). The results revealed that (a) LBT bias in the physical reality showed a handedness-related leftward pseudoneglect, however, similar handedness-related pseudoneglect in VR has not been found. (b) Comparing LBT bias in physically real and VR environments showed rightward drift in VR environments independently to the degree of handedness. (c) The schizotypy has no association with handedness, however, the cognitive schizotypy is related to the LBT bias. Higher cognitive schizotypy in VR associated with left hemispatial pseudoneglect. In conclusion, schizotypy is associated with ambiguous behavioral and cognitive functional laterality. In individuals with high cognitive schizotypy, the VR environment enhanced the representational articulation of the left hemispace. This effect may be originated from the enhancement of the right hemisphere overactivation and is followed by a lower mental control of the overt behavior.