Dynamics of Face and Head Movement in Infants with and without Craniofacial Microsomia: An Automatic Approach

BACKGROUND: Craniofacial microsomia (CFM) is a congenital condition associated with malformations of the bone and soft tissue of the face and the facial nerves, all of which have the potential to impair facial expressiveness. We investigated whether CFM-related variation in expressiveness is evident as early as infancy. METHODS: Participants were 113 ethnically diverse 13-month-old infants (n = 63 cases with CFM and n = 50 unaffected matched controls). They were observed in 2 emotion induction tasks designed to elicit positive and negative effects. Facial and head movement was automatically measured using a computer vision–based approach. Expressiveness was quantified as the displacement, velocity, and acceleration of 49 facial landmarks (eg, lip corners) and head pitch and yaw. RESULTS: For both cases and controls, all measures of expressiveness strongly differed between tasks. Case–control differences were limited to infants with microtia plus mandibular hypoplasia and other associated CFM features, which were the most common phenotypes and were characterized by decreased expressiveness relative to control infants. CONCLUSIONS: Infants with microtia plus mandibular hypoplasia and those with other associated CFM phenotypes were less facially expressive than same-aged peers. Both phenotypes were associated with more severe involvement than microtia alone, suggesting that infants with more severe CFM begin to diverge in expressiveness from controls by age 13 months. Further research is needed to both replicate the current findings and elucidate their developmental implications.