Movement-related differences in infants with high and low likelihood of autism: A longitudinal study using automated kinematic tracking

Motor behaviour has been shown to differ, both in terms of complexity and variability, between neurotypical and autistic populations. However, there is little research on the early development of specific kinematic features and their timing of emergence in early life. The current study examined the early development of kinematic features (duration, range, velocity, acceleration, entropy and jerk) in infants with a high and low likelihood of autism using automatic pose estimation models. We evaluated weekly home-recorded videos of naturalistic, spontaneous movement (controlling for clothing, background and posture) from 60 participants (705 videos) longitudinally over the first six months of life. We automatically extracted kinematic data using computer vision, including motion of the shoulders, elbows, hips, and knees. We found that the groups differed in the variability of the entropy, whereby the variability of Entropy was lower in HL compared with LL infants across the first six months of infancy. These results suggest that it may be possible to spot very early differences in motor behaviour indicative of neural atypicalities common in autism.