Schizotypal personality traits influence idiosyncratic initiation of saccadic face exploration

Visual face exploration is usually biased to the left half of a presented face. Recent findings now indicate that the first saccade in face exploration has a strong idiosyncratic component with around 30% of healthy individuals showing a consistent rightward bias. We investigated in a random sample of 64 right-handed healthy participants whether this rightward bias might relate to individual differences, i.e. a psychotic-like thinking style (schizotypy). Elevated positive (magical ideation) but not negative (physical anhedonia) schizotypy scores accounted for a pronounced left-face preference for first saccades. Furthermore, when using magical ideation and physical anheonia to group individuals according to their median scale scores into four groups (either both scores elevated or low, or mixed with one score elevated, one low), participants with both scores elevated exhibited the most pronounced left-face preference and participants with both scores low the least. The same participant groups did not differ with respect to their side preference in exploring fractals nor for other exploration parameters such as first fixation duration, number of saccades or scanpath length. These findings indicate pronounced right-hemispheric dominance for face exploration in healthy individuals with elevated positive schizotypal thought. These findings contrast with expectations from studies with schizophrenic patients, and point to the relevance of individual differences in lateralized face processing.