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

Area of Science:

• Neuroscience
• Motor Control
• Developmental Disorders

Background:

• Individuals with autism spectrum disorder (ASD) often display challenges with maintaining postural stability.
• The specific motor control mechanisms and their association with gross motor activities like stepping remain unclear.

Purpose of the Study:

• To investigate postural control differences between individuals with ASD and typically developing (TD) controls.
• To examine the relationship between postural control, stepping abilities, and ASD symptom severity.

Main Methods:

• Seventeen individuals with ASD and 20 TD controls (ages 6-19) underwent postural control tests (standing stances) and a stepping task.
• Center of pressure (COP) variables, mutual information (MI) between mediolateral (ML) and anteroposterior (AP) directions, and stepping adjustments were analyzed.
• Correlations between motor measures and ASD symptom severity (ADOS-2, ADI-R) were assessed.

Main Results:

• Individuals with ASD demonstrated increased COP trajectory length and reduced MI during dynamic sway compared to TD controls.
• During stepping, ASD individuals showed reduced lateral sway, shorter body transfer duration, and increased velocity.
• Greater ML sway variability and reduced lateral sway during stepping correlated with more severe restricted and repetitive behaviors in ASD.

Conclusions:

• Reduced MI in ASD suggests impaired coordination of joint movements during dynamic postural adjustments.
• Decreased lateral sway during stepping in ASD may indicate motor rigidity affecting balance and gait.
• Shared pathological processes may underlie both postural control deficits and repetitive behaviors in ASD.