Atypical Cognitive Vergence Responses In Children With Attention Deficit Hyperactivity Disorder But Not With Autism Spectrum Disorder In A Facial Emotion Recognition Task

Background: Facial expression of emotion is fundamental to human social interactions. Attention to relevant cues in ADHD and ASD patients are believed to underlie difficulties in recognizing emotions. Cognitive vergence eye movements during gaze fixation have a role in attention. Here we evaluate a possible role of cognitive vergence in facial emotion recognition. Methods: We recorded eye vergence from children with ADHD (n ​= ​27), ASD (n ​= ​18) or ADHD&ASD (n ​= ​15) and from neurotypical (NT; n ​= ​31) children during a facial emotion recognition task. Results: Vergence responses to relevant stimuli were stronger than those to distractor stimuli. ADHD and ADHD&ASD children showed shorter gaze fixation duration and weaker cognitive vergence responses to the eye regions of the face stimuli compared to neurotypically developing children. In contrast, gaze behavior and vergence responses of ASD children resembled that of neurotypically developing children. Conclusion: These results provide evidence for the idea that impaired recognition of facial expression of emotion is a problem of attending the relevant cues to adequately recognize facial expressions. As ASD patients resembled that of NT, cognitive vergence represents an etiological difference between ADHD and ASD.