Understanding macrographia in children with autism spectrum disorders

Area of Science:

• Neuroscience
• Developmental Psychology
• Biomedical Engineering

Background:

• Children with autism spectrum disorder (ASD) often experience significant difficulties with handwriting, including letter formation and size consistency.
• Motor control deficits are frequently observed in individuals with ASD, potentially contributing to these fine motor challenges.

Purpose of the Study:

• To investigate the underlying motor control factors contributing to handwriting difficulties in children with ASD.
• To examine fundamental handwriting movements and the role of neuromotor noise in children with ASD.

Main Methods:

• Compared handwriting movements of 26 children with ASD (aged 8-13) and 17 typically developing controls using a graphics tablet.
• Analyzed stroke dimensions, movement variability, velocity, and neuromotor noise using power spectral density analysis.

Main Results:

• Children with ASD demonstrated significantly larger stroke height and width, greater movement trajectory variability, and higher movement velocities.
• Higher absolute levels of neuromotor noise, particularly in frequency bands >3 Hz, were observed in children with ASD.

Conclusions:

• Instability in fundamental handwriting movements and atypical biomechanical strategies contribute to the larger and less consistent handwriting observed in children with ASD.
• Neuromotor noise plays a significant role in the motor control deficits affecting handwriting in this population.