Valentina Silvestri¹, Chiara Dondena¹, Hermann Bulf¹; ¹University of Milano-Bicocca, Department of Psychology

Beyond faces, hands carry significant social information and are among the most expressive components of the human body, providing insight into actions, gestures, emotions, and intentions. The ontogenetic necessity to tune into hands is revealed by evidence showing infants’ notable sensitivity to hands, reflecting their rich visual and tactile experience with this socially meaningful body part (Aslin, 2009; Deák et al., 2014). More recently, it has been shown that infants are sensitive to the structure of hands, preferring scrambled over intact hands (Jubran et al., 2019). However, in the study of Jubran and colleagues (2019), scrambled hands were created by altering the location of one or more fingers within the hand (e.g., the pinky repositioned between the thumb and the index finger), thus breaking the overall gestalt. Here, we explore whether infants’ representation of hands is guided by anatomical coherence when the overall gestalt of the hand is maintained intact and the anatomical plausibility is disrupted (i.e., anatomically implausible but configurally recognizable hands). Six-month-old infants were presented with intact and scrambled hands, where all fingers were relocated to positions inconsistent with their natural anatomical origin (e.g., placing a thumb in the position of the pinky) while preserving the overall hand configuration. Infants’ eye gaze to the right and left hands, presented in both dorsal and palm view, was automatically recorded using an eye tracker within a preferential-looking task where intact and scrambled hands were simultaneously presented. Preliminary results reveal that infants’ preference for scrambled over intact hands depends on hand view (palm vs. dorsal) and laterality (right vs. left hand) (p = .03). Our findings shed light on the nature of the visual information underlying infants’ sensitivity to hands, advancing our understanding of the mechanisms driving perceptual tuning to hands.