Is There a Specific Motor Signature of Autism? Exploratory Studies From Human–Machine Interaction

Autism spectrum disorder (ASD) is a heterogeneous group of neurodevelopmental disorders whose core symptoms are impairments in socio-communication and repetitive interests and stereotypies. Although motor impairments are not cardinal symptoms per se, many children with ASD have postural and motor coordination disabilities. Here, we investigate them dynamically through human–machine interaction, analysing data previously collected during two experiments: a joint attention (JA) task involving a human–robot interaction with children with ASD and typically developing (TD) controls; a motor imitation task involving a tightrope walker (TW) avatar, children with ASD, with developmental coordination disorder (DCD) and TD children. Participants were recorded using RGB and RGB-D cameras, allowing for the extraction of kinematic and spectral features. Movement power spectral density (MPSD) analysis demonstrated that children with ASD displayed more energetically costly behaviors across all frequencies when contrasted with TD children (both experiments) and children with DCD (TW experiment). These findings affirm the distinct motor complexity of children with ASD, suggesting the presence of a unique motor signature potentially different from that observed in children with DCD.