Altered automatic face processing in individuals with high-functioning autism spectrum disorders: Evidence from visual evoked potentials Takako Fujita a,b , Yoko Kamio c , Takao Yamasaki a, *, Sawa Yasumoto b , Shinichi Hirose b , Shozo Tobimatsu a a Department of Clinical Neurophysiology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan b Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan c Department of Child and Adolescent Mental Health, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan Social dysfunction is a fundamental problem in autism spectrum disorders (ASDs). Consequently, face processing in individuals with ASD has been intensively studied on both the behavioral and neurological level. A range of face processing abnormalities has been described in individuals with ASD (Behrmann et al., 2006; Berger, 2006; Dawson, Webb, & McPartland, 2005; Grelotti, Gauthier, & Schultz, 2002; Sasson, 2006; Schultz, 2005), and their relatives (Baron-Cohen & Hammer, 1997; Bo ¨ lte & Poustka, 2003; Wallace, Sebastian, Pellicano, Parr, & Bailey, 2010). Some researchers have proposed face processing as a candidate for a cognitive ASD endophenotype (Dawson et al., 2002; Wallace et al., 2010; Wilson, Brock, & Palermo, 2010). Face processing relies on a distributed, patchy network of cortical regions and subcortical structures (Atkinson & Adolphs, 2011). The core cortical regions include the inferior occipital gyri (early perception of facial features), the lateral fusiform Research in Autism Spectrum Disorders 7 (2013) 710–720 A R T I C L E I N F O Article history: Received 26 October 2012 Received in revised form 7 March 2013 Accepted 7 March 2013 Keywords: Autism spectrum disorder (ASD) Visual evoked potentials (VEPs) Automatic face processing Subliminal perception Fearful face A B S T R A C T Individuals with autism spectrum disorders (ASDs) have different automatic responses to faces than typically developing (TD) individuals. We recorded visual evoked potentials (VEPs) in 10 individuals with high-functioning ASD (HFASD) and 10 TD individuals. Visual stimuli consisted of upright and inverted faces (fearful and neutral) and objects presented subliminally in a backward-masking paradigm. In all participants, the occipital N1 (about 100 ms) and P1 (about 120 ms) peaks were major components of the evoked response. We calculated ‘‘subliminal face effect (SFE)’’ scores by subtracting the N1/P1 amplitudes and latencies of the object stimuli from those of the face stimuli. In the TD group, the SFE score for the N1 amplitude was significantly higher for upright fearful faces but not neutral faces, and this score was insignificant when the stimuli were inverted. In contrast, the N1 amplitude of the HFASD subjects did not show this SFE in the upright orientation. There were no significant group differences in SFE scores for P1 amplitude, latency, or N1 latency. Our findings suggest that individuals with HFASD have altered automatic visual processing for emotional faces within the lower level of the visual cortex. This impairment could be a neural component of the disrupted social cognition observed in individuals with HFASD. ß 2013 Elsevier Ltd. All rights reserved. * Corresponding author at: Department of Clinical Neurophysiology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. Tel.: +81 92 642 5542; fax: +81 92 642 5545. E-mail address: yamasa@neurophy.med.kyushu-u.ac.jp (T. Yamasaki). Contents lists available at SciVerse ScienceDirect Research in Autism Spectrum Disorders Jo u rn al h om ep ag e: h ttp ://ees .elsevier .co m /RASD/d efau lt.as p 1750-9467/$ – see front matter ß 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.rasd.2013.03.001