Dynamic Facial Information Processing in Autism Spectrum Disorders and Typical Development: Social Attention Paradigms
Objectives: The aims of this study was to characterize, thanks to eye behavioral indices (gaze focus), and eye physiological indices (pupil diameter), responses to facial micromovements and to facial macromovements in typical development and in ASD development.
Methods: Gaze focus (gaze patterns on whole faces and eyes and mouth region, scan time, fixation duration) and pupil responses were recorded with an eye tracking system in 100 typical and 90 ASD children (3-12 years old) during 3 paradigm: i/ Micromovement paradigm: presentation of statics and dynamics neutral faces; ii/ Emotional macromovement paradigm: presentation of dynamics neutral and emotional faces (happy and sad faces); iii/ Socio-attentional macromovement paradigm: presentation of dynamics faces orienting their gaze towards an object.
Results: In both groups, micromovements and emotional macromovements enhance gaze focus in response to faces, but the gaze focus is decreased in ASD group compared to control. Concerning pupil responses, micromovements and emotional macromovements enhance pupil dilation in response to faces only in control group. Socio-attentional macromovements induce gaze orientation towards the object congruent with the gaze of the face presented mainly in control group. Maturation of gaze focus and pupil response was found in both group.
Conclusions: These results underlie atypical processing of emotional and social facial motion perception which could in turn result in impaired social interaction in autistic pathology.