Functional changes during visuo-spatial working memory in autism spectrum disorder: 2-year longitudinal functional...

Area of Science:

• Neuroscience
• Developmental Psychology
• Cognitive Science

Background:

• Working memory is crucial for cognitive development and academic success.
• Autism spectrum disorder (ASD) is associated with altered neural processing.
• Understanding longitudinal changes in neural correlates of working memory in ASD is important for identifying developmental trajectories.

Purpose of the Study:

• To longitudinally examine functional brain changes in working memory in youth with and without ASD over two years.
• To investigate the impact of increasing cognitive load on neural responses in these groups.
• To compare developmental trajectories of neural activation between typically developing children and children with ASD.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to assess brain activity.
• A visuo-spatial 1-back task with four difficulty levels was administered.
• 14 children with ASD and 15 typically developing children (ages 7-13) were scanned at baseline and followed up approximately two years later.

Main Results:

• Despite similar task performance, significant differences in the developmental trajectories of neural responses were observed.
• Typically developing children showed increased load-dependent activation in frontal, parietal, and occipital lobes over time.
• Children with ASD exhibited minimal age-related changes in load-dependent activation and greater default mode network deactivation with increasing cognitive load.

Conclusions:

• Children with ASD demonstrate inadequate modulation of neural activity with increasing cognitive demands, which does not mature into adolescence.
• This diminished ability to modulate neural activity suggests greater vulnerability to academic and social demands during adolescence for youth with ASD.
• Findings highlight critical differences in the maturation of cognitive control networks in ASD.