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 < 0.01), and increased body transfer velocity (p = 0.02) compared to controls. Greater neutral stance COP ML variability (r = 0.55, p = 0.02) and decreased lateral sway (r = − 0.55, p = 0.02) when stepping were associated with more severe restricted and repetitive behaviors in participants with ASD. Conclusions: We found that individuals with ASD showed reduced MI during circular sway suggesting a reduced ability to effectively coordinate joint movements during dynamic postural adjustments. Additionally, individuals with ASD showed reduced lateral sway when stepping indicating that motor rigidity may interfere with balance and gait. Postural control and stepping deficits were related to repetitive behaviors in individuals with ASD indicating that motor rigidity and key clinical issues in ASD may represent overlapping pathological processes.

Medical vulnerability of individuals with Down syndrome to severe COVID-19–data from the Trisomy 21 Research Society and the UK ISARIC4C survey

“…The proportion of cases living in a residential care facility was higher in the clinician than family/caregiver reports (134 (26%) versus 23 (5%)). The majority of cases (784 (93%)) had full trisomy 21 and moderate level of intellectual disability (580 (62%)), similar to that observed in the population of individuals with DS at large [11] . About half of the cases were admitted to hospital (581 (56%)), of which 279 (50%) were admitted to an ICU and 207 (29%) were connected to a mechanical ventilator.…”

“…DS is associated with several co-occurring health conditions including obesity, diabetes, hypotonia, obstructive sleep apnea, craniofacial dysmorphogenesis, and congenital heart defects, as well as gastroesophageal reflux that may contribute to the increased risk of respiratory tract infection [ 1 , [11] , [12] , [13] ]. Moreover, adults with DS have many age-related health conditions including Alzheimer's disease [14] , that often occur 20–25 years earlier than in individuals without DS which is a profile that suggests premature aging [ 1 , 11 , 14 ]. Yet, there is also evidence that persons with DS are protected from cardiovascular disease, including hypertension [15] .…”

Capturing cognitive and behavioral variability among individuals with Down syndrome: a latent profile analysis

“…Because expressive language is an area of particular weakness in the DS phenotype and is often a target of interventions, it is critical to include moving forward. Techniques such as expressive language sampling will be particularly fruitful due to the ability to circumvent the issue of floor effects associated with standardized norm-referenced tests while preserving psychometric quality [ 85 , 86 ]. To this point, other measures of cognition in future research should be mindful of the assessment form and type of score used to minimize floor effects [ 87 ].…”

Atypical Head Movement during Face‐to‐Face Interaction in Children with Autism Spectrum Disorder

“…In the field of motor control, individuals with ASD have been found to exhibit motor abnormalities in postural control, gait stability, arm movements, gross and fine motor control [Bojanek, Wang, White, & Mosconi, 2020; Fournier, Hass, Naik, Lodha, & Cauraugh, 2010]. In particular, stereotyped behavior is one of the two indispensable characteristics of ASD [American Psychiatric Association, 2013].…”