Changes in Parietal Cortex Response in Children with Autism Followed By a Visualizing Reading Intervention

Background: Poor language comprehension is a major clinical feature of autism spectrum disorders (ASD). Previous studies suggest that individuals with ASD may rely on compensatory mechanisms such as increased use of visuospatial abilities, which are relatively spared or even superior in ASD, to better facilitate language comprehension. Such compensation may underlie altered brain activity and connectivity in ASD individuals while processing language tasks. The current study takes a translational neuroimaging approach to use visual spatial strength in ASD to address language comprehension difficulties through a reading intervention.

Objectives: The main objective of this study was to test the impact of an intensive visual imagery-based reading intervention in improving language comprehension and in changing the brain circuitry underlying language in children with ASD.

Methods: Functional MRI data were used from 20 high-functioning children with ASD and 13 typically developing (TD) control participants. The ASD participants were randomly assigned to a Wait-list control group (ASD-WLC; n = 10) and an Experimental group (ASD-EXP; n = 10). The TD group was scanned once and both the ASD-WLC and ASD-EXP groups were scanned pre- and post-intervention, with only the ASD-EXP group receiving the intervention before their second scan. Participants went through an established reading intervention program (visualizing and verbalizing for language comprehension and thinking; 10-week, 200 hours of face-to-face instruction) created by the Lindamood-Bell Learning Processes. In the fMRI scanner, the participants read a series of sentences and made judgments as to whether the sentences made sense or not (e.g., When I want to play baseball, I grab a swimsuit and go to the pool). fMRI data were analyzed using AFNI and SPM8 softwares.

Results: The main results are: 1) before intervention, the ASD participants, relative to TD, showed significantly reduced activation (p < .05, corr.) in frontal (medial prefrontal cortex, right superior frontal gyrus), ventral temporal (left parahippocampal area, right fusiform gyrus), and occipital regions (bilateral middle occipital, right cuneus) and increased activation in left inferior parietal lobule while processing absurd and control sentences; II) the ASD-EXP group showed an increase in brain activation in occipital regions (bilateral middle/superior occipital and calcarine sulcus) compared to the ASD-WLC group post-intervention; III) intervention-related changes in brain activation were observed in the ASD-EXP group post-intervention in right precuneus, calcarine, and superior parietal lobule; and IV) multiple regression analysis, while controlling for verbal IQ, showed that changes (pre-post) in Gray Oral Reading Test (GORT) scores significantly predicted post-intervention activation in the ASD-EXP group in regions such as precuneus, middle occipital, and right IFG.

Conclusions: The findings of this study revealed that reading intervention increased the brain activity in ASD-EXP children in parietal areas associated with visual imagery. It should be noted that the increase in activation was accompanied by improvement in language comprehension in these participants. This study provides novel evidence of improvement in brain functioning in autism in the context of an innovative and rigorous imagery-based reading intervention that is designed to use nonverbal sensory input, an area relatively spared in individuals with ASD.