Attentional effects of gaze shifts are influenced by emotion and spatial frequency, but not in autism

OBJECTIVE: Impaired gaze following is an important hallmark of autism spectrum disorders (ASDs) in clinical settings. Yet, ASD subjects perform normally on laboratory tasks involving gaze shifts. We investigated this contradiction, hypothesizing that impaired gaze following in ASDs is not related to basic impairments in attention orienting but to impaired emotion perception and abnormal processing of spatial frequencies (i.e., local and global information). METHOD: We tested 30 high-functioning, school-age children with ASDs and 30 age- and IQ-matched controls on a task involving gaze shifts that cue the location of targets. The cueing faces differed in emotionality and were filtered for different spatial frequencies. We recorded behavioral responses (reaction times) and brain responses (event-related potentials). RESULTS: ASD subjects performed normally when neutral faces were used. However, emotional faces elicited modified face and gaze cue processing in control subjects, but not in the ASD subjects. Furthermore, the control group was biased toward the use of low spatial frequencies (global information) to process gaze cues, whereas the ASD group was biased toward the use of high spatial frequencies (local information). CONCLUSIONS: We conclude that impaired gaze following in ASDs is related to impaired emotion processing. Moreover, ASD subjects show an abnormal reliance on local information to process gaze cues