The Impact of a Visualization Language Intervention On Brain Activation and Connectivity in Children with Autism

Background:  Deficits in language comprehension have been widely reported in children with autism spectrum disorders (ASD). Recent evidence from neuroimaging research suggests that people with ASD tend to recruit visuospatial imagery to comprehend language. Such increased reliance on visuospatial regions may also underlie weaker coordination between primary visual and association areas in ASD, especially while processing complex language tasks. Of especial interest is the atypical brain activation and weaker connectivity in autism and how such connections can be strengthened through cognitive and behavioral intervention. 

Objectives:  This fMRI study investigates brain activation and connectivity patterns, using a visual imagery language task, in a longitudinal design before and after a 10-week visualizing language intervention in high-functioning children with ASD. The main objective is to determine whether deficits in functional activation and connectivity are reversible and how such changes reflect behavior.

Methods: Currently, 14 children with ASD (ages 8-13 years) have taken part in a pre-imaging session, with 8 children receiving the intervention soon after the initial fMRI scan, and 6 wait-list control children.  Seven children so far have returned for the post-imaging session, 3 having received the intervention between scans, and 4 wait-list controls. A language comprehension task, presented while the children underwent fMRI, included high and low imagery sentences. This data were used to investigate intervention related effects on brain activation and connectivity. Data were acquired from a Siemens 3.0T Allegra head-only scanner and analyzed using SPM8. 

Results:  (1) In children with ASD (n = 14), the pre-intervention brain response to visual imagery sentences included frontal regions (e.g., left middle frontal gyrus, superior frontal gyrus, dorsolateral prefrontal cortex, and Broca’s area) and visual regions (e.g., lingual gyrus and middle occipital gyrus); (2) Greater activation was found in posterior brain regions (i.e., left precuneus and posterior cingulate cortex) when interpreting high imagery compared to low imagery sentences; (3) Children with ASD who received the intervention between imaging sessions (n = 3) showed a trend towards increased activation in the medial prefrontal cortex pre-to post-imaging session. This trend was not seen in the wait-list controls (n = 4); (4) Lower symptom severity on the Social Communication Questionnaire (SCQ) was correlated with greater activation in frontal regions (e.g., left middle frontal gyrus and Broca’s area) at the post-intervention imaging session; (5) A functional connectivity analysis revealed a trend of greater synchronization between Broca’s area and the rest of the language network in the children with ASD who received the intervention (n =3) compared to the wait-list controls (n = 4).

Conclusions: This study introduces a novel and intensive language-based remediation treatment that is designed to use nonverbal sensory input, an area relatively intact in individuals with ASD, in order to develop oral and written language comprehension, establish vocabulary, and develop higher order thinking skills. Our preliminary findings reveal the plasticity of the brain in children with ASD, and suggest improvement of neural activity and synchronization due to targeted intervention. We highly anticipate further interesting results as we continue to recruit participants for this study.