Neural and gaze pattern responses to happy faces in autism: Predictors of adaptive difficulties and re-evaluation of the social motivation hypothesis.

BACKGROUND

The "Social Motivation" hypothesis posits that social deficits in autism spectrum disorder (ASD) arise from altered reward perception. However, few studies have examined neural and behavioral responses to social reward-related cues in low functioning ASD children with limited cognitive or language abilities.

OBJECTIVE

This study investigated if young children with ASD show atypical gaze towards happy faces and its association with altered brain reward responses.

METHODS

Eye-tracking was performed in 36 ASD and 36 typically developing (TD) children (2.5-6 years) viewing happy faces of children or emoticons. Functional near infrared spectroscopy was used to record group differences in orbitofrontal cortex (OFC) activation simultaneously.

RESULTS

Children with ASD showed increased pupil diameter and OFC activation compared to TD children when viewing all happy faces and gazed less at the eyes of actual faces and the mouths of emoticons. These atypical responses was associated with lower adaptive behavior scores and greater symptom severity.

CONCLUSION

Our research reveals distinct neural hyperactivity and viewing patterns in young children with ASD when presented with reward-related facial stimuli. These results contradict the Social Motivation Hypothesis. Children with ASD exhibit heightened levels of arousal and employ less efficient facial processing strategies. This heightened demand for cognitive resources could have long-term effects on children's well-being and may hinder their ability to develop adaptive skills effectively.