Postural control processes during standing and step initiation in autism spectrum disorder.

ABSTRACT: BACKGROUND:Individuals with autism spectrum disorder (ASD) show a reduced ability to maintain postural stability, though motor control mechanisms contributing to these issues and the extent to which they are associated with other gross motor activities (e.g., stepping) are not yet known. METHODS:Seventeen individuals with ASD and 20 typically developing (TD) controls (ages 6-19?years) completed three tests of postural control during standing. During the neutral stance, individuals stood with their feet shoulder width apart. During the Romberg one stance, they stood with feet close together. During the circular sway, participants stood with feet shoulder width apart and swayed in a circular motion. The standard deviation (SD) of their center of pressure (COP) in the mediolateral (ML) and anteroposterior (AP) directions and the COP trajectory length were examined for each stance. We also assessed mutual information (MI), or the shared dependencies between COP in the ML and AP directions. Participants also completed a stepping task in which they stepped forward from one force platform to an adjacent platform. The amplitude and duration of anticipatory postural adjustments (APAs) were examined, as were the maximum lateral sway, duration, and velocity of COP adjustments following the initial step. We examined stepping variables using separate one-way ANCOVAs with height as a covariate. The relationships between postural control and stepping measures and ASD symptom severity were assessed using Spearman correlations with scores on the Autism Diagnostic Observation Schedule-Second Edition (ADOS-2) and the Autism Diagnostic Interview-Revised (ADI-R). RESULTS:Individuals with ASD showed increased COP trajectory length across stance conditions (p?=?0.05) and reduced MI during circular sway relative to TD controls (p?=?0.02). During stepping, groups did not differ on APA amplitude (p?=?0.97) or duration (p?=?0.41), but during their initial step, individuals with ASD showed reduced ML sway (p?=?0.06), reduced body transfer duration (p?

SUBMITTER: Bojanek EK 

PROVIDER: S-EPMC6945692 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature