Efficacy of Reading Intervention on the Brain Connectivity in Autism

The overarching goal of this proposal is to test the impact of a comprehensive reading intervention program on changing the neurobiological mechanisms underlying reading comprehension deficits in children with autism spectrum disorders (ASD). There is evidence that as many as 65% of children with ASD have a deficit in reading comprehension. This ultimately has profound impact on language, learning, and academic success (Nation, Clarke, Wright, \& Williams, 2006). Poor reading comprehension in children with autism is often masked by their relative strength in decoding. Moreover, reading comprehension in general is not well-understood, and as a result, current treatments are limited in its potential and in its effectiveness. In this project, the investigators will test a group of children with ASD and NT control participants who share common characteristic of average level decoding along with below average reading comprehension. The investigators also have included an additional NT group without any reading comprehension deficits, and this group will serve as another control for additional comparisons. The investigators will test the efficacy of an intensive reading intervention training program, visualizing and verbalizing for language comprehension and thinking (V/V), and its effects on changing the brain circuitry underlying reading comprehension in children with ASD. The project will use multimodal neuroimaging with task-based functional MRI, resting state functional MRI, diffusion imaging, and neuropsychological testing. It should be noted that neuroimaging as well as behavioral studies of language in autism have largely ignored a subgroup of children with comprehension deficits. The proposed project addresses this critical gap by targeting brain plasticity in children with ASD (age: 7-13 years). Average decoding ability with below average comprehension of language in children is an important problem of academic and public health significance. The outcome of this study will throw more light on this important subgroup of children. In addition, it will test the efficacy of an intervention that can, in the long-run, help NT and children with reading problems to achieve academic success. Findings may provide important preliminary steps in using V/V intervention in schools.

This project will use multimodal neuroimaging [functional MRI, structural MRI, and diffusion weighted imaging (DWI)] to assess changes in brain function and white matter connectivity in autism. This will be accomplished using 4 groups of participants matched on age, gender and IQ: 1) children with ASD who will undergo the V/V intervention after their first MRI scan (ASD-EXP) (n=50); 2) children with ASD who will receive the intervention at the end of the trial (wait-list controls) (ASD-WLC) (n=50); 3) NT children with reading comprehension deficits who will receive intervention after their first MRI scan (NT-EXP) (n = 50); and 4) NT (n = 50) control participants (no reading comprehension deficits) who will be scanned twice but will not receive any intervention. A total of 200 participants (with 20 additional participants to account for attrition) will take part in this project. It should be noted that neuroimaging as well as behavioral studies of language in autism have largely ignored children with comprehension deficits. The proposed project addresses this critical gap by targeting brain plasticity in ASD and NT children (age: 7-13 years), with the following three independent, but inter-related specific aims.

AIM #1: Examine the differential impact of V/V intervention on the functional organization (activation and functional connectivity) of the brain's reading network (Koyama et al., 2011) in ASD and NT children who share reading comprehension deficits.

Hypothesis: Along with improvement in comprehension in both groups, the investigators predict that the connectivity between classic language areas and regions involved in visual/visuospatial processing will be stronger in ASD-EXP children compared to NT-EXP children after intervention.

AIM #2: Test the impact of V/V intervention on the microstructural connectivity of the white matter underlying reading network (primarily AF: the arcuate fasciculus and UF: the uncinate fasciculus) in ASD and NT children who share similar reading comprehension deficits.

Hypothesis: At post-scanning, white matter connectivity of the AF and UF (connecting frontal and temporal areas) will be increased in children who receive V/V intervention compared to themselves and to waitlist controls. It is expected that the extent of this change will differ between ASD-EXP and NT-EXP groups.

AIM #3: Establish brain-behavior relationship by testing how improvements in language skills (decoding, comprehension, fluency and other components) and autism symptoms predict post-intervention changes in neurobiological and behavioral profiles in ASD and NT children.

Hypotheses: 1) Improvement in comprehension (as measured by Gray Oral Reading Test) following V/V intervention will predict increased activation, functional connectivity, and white matter connectivity in the reading network in NT-EXP and ASD-EXP groups; 2) ASD symptom severity will negatively predict improvement in comprehension and in reading network response, and may help differentiate the nature of language deficits between ASD-EXP and NT-EXP groups.

The outcomes of this study will inform us about intervention-related changes in brain and behavior in ASD children with language deficits. This, in turn, may have translational significance in education. The inclusion of NT-EXP and NT control groups provide a unique opportunity to glean further into the nature of reading deficits in ASD and NT children and to the specificity of such deficits in ASD.