Interactions between eye movements and posture in children with neurodevelopmental disorders

Area of Science:

• Neuroscience
• Developmental Psychology
• Ophthalmology

Background:

• Dual-tasking, or performing multiple tasks simultaneously, is common but challenging.
• Children with neurodevelopmental disorders (NDDs) may experience greater performance decrements when sharing attention.
• Postural demands can further tax attentional resources, potentially exacerbating NDD-related deficits.

Purpose of the Study:

• To investigate if postural conditions (sitting vs. standing) differentially affect eye movement performance in children with NDDs during high-attentional load tasks.
• To compare these effects between children with attention deficit and hyperactive disorder (ADHD), dyslexia, high functioning autism spectrum disorder (HFASD), and typically developing (TD) children.

Main Methods:

• Evaluated 104 children (26 per group: ADHD, dyslexia, HFASD, TD), matched for age, sex, and IQ.
• Assessed eye movement performance on visually-guided saccade, memory-guided saccade, and fixation tasks.
• Compared performance in a sitting (single task) versus a standing (dual task) condition.

Main Results:

• Children with NDDs (ADHD, dyslexia, HFASD) exhibited poorer eye movement performance during the fixation task in the standing condition compared to the sitting condition.
• Typically developing children showed no significant difference in fixation task performance between sitting and standing conditions.
• No significant differences were observed for the saccade tasks across conditions or groups.

Conclusions:

• Children with NDDs have limited attentional resources, impairing oculomotor control during high-attentional load tasks, particularly under postural challenge (standing).
• This attentional deficit affects their ability to maintain both accurate eye movements and postural stability simultaneously.
• Findings highlight the complex interplay between attention, oculomotor function, and postural control in NDDs.