Investigating intra-individual variability of face scanning in autistic children

We investigated the intra-individual variability of face scanning in autistic children to represent a new avenue for understanding abnormal face scanning in autism spectrum condition. Across four studies, we used eye-tracking techniques to systematically examine the variability of face scanning patterns in autistic children when performing different tasks and scanning different types of faces. Autistic and non-autistic children were asked to complete a face judgment task (Study 1, age range: 4.9–7.2 years), a face recognition task (Study 2, age range: 4.7–7.6 years), a facial expression recognition task (Study 3, age range: 4.3–7.4 years), and a dynamic facial expression free viewing task (Study 4, age range: 2.5–5.6 years). In addition, we conducted Study 5 using houses as stimuli to test the specificity of the results to faces (age range: 4.9–7.2 years). We found that scan pattern similarity between different face presentations was lower in autistic children than non-autistic children, which was robust to variations in experimental methods. Furthermore, the decreased scan pattern similarity in autism spectrum condition was evident in both viewing faces and houses. These results suggest that the scanning patterns of autistic children are noisier and variable. It might represent a new avenue for the understanding of core symptoms in autism spectrum condition. Lay abstract Atypical face scanning is suggested to be related to social interactions and communicative deficits in autistic children. We systematically examined whether autistic and non-autistic children used consistent scanning patterns when performing different tasks and scanning different types of faces. We found that autistic children scanned faces more variably than non-autistic children: While non-autistic children used more consistent scanning patterns, autistic children’s scanning patterns changed frequently when watching different faces. Autistic children’s variable face scanning patterns might delay and impair face processing, resulting in a social interaction deficit. What’s more, variable scanning patterns may create an unstable and unpredictable perception of the environment for autistic children. Developing in such an unstable environment might motivate autistic children to retract from the environment, avoid social interaction, and focus instead on the performance of repetitive behavior. Therefore, studying face scanning variability might represent a new avenue for understanding core symptoms in autistic people.