Network‐based analysis reveals stronger local diffusion‐based connectivity and different correlations with oral language skills in brains of children with high functioning autism spectrum disorders

Abstract

Neuroimaging has uncovered both long-range and short-range connectivity abnormalities in the brains of individuals with autism spectrum disorders (ASD). However, the precise connectivity abnormalities and the relationship between these abnormalities and cognition and ASD symptoms have been inconsistent across studies. Indeed, studies find both increases and decreases in connectivity, suggesting that connectivity changes in the ASD brain are not merely due to abnormalities in specific connections, but rather, due to changes in the structure of the network in which the brain areas interact (i.e., network topology). In this study, we examined the differences in the network topology between high-functioning ASD patients and age and gender matched typically developing (TD) controls. After quantitatively characterizing the whole-brain connectivity network using diffusion tensor imaging (DTI) data, we searched for brain regions with different connectivity between ASD and TD. A measure of oral language ability was then correlated with the connectivity changes to determine the functional significance of such changes. Whole-brain connectivity measures demonstrated greater local connectivity and shorter path length in ASD as compared to TD. Stronger local connectivity was found in ASD, especially in regions such as the left superior parietal lobule, the precuneus and angular gyrus, and the right supramarginal gyrus. The relationship between oral language ability and local connectivity within these regions was significantly different between ASD and TD. Stronger local connectivity was associated with better performance in ASD and poorer performance in TD. This study supports the notion that increased local connectivity is compensatory for supporting cognitive function in ASD.

Disrupted Functional Brain Networks in Autistic Toddlers

“…However, disturbed temporal coordination of these local and global synchronization processes at different stages of brain maturation might lead to neuropsychiatric disorders (Uhlhaas and Singer, 2012). Several patterns of over-and under-connectivity at distinct spatial and temporal scales have been reported in autism ( Just et al, 2012;Kana et al, 2011;Li et al, 2012;Muller et al, 2011;Murias et al, 2007;Vissers et al, 2012;Wass, 2011). A recurrent pattern of local over-connectivity (most pronounced within frontal areas), and decreased connectivity from frontal to other brain areas has been found in autism Just et al, 2012), supporting our current findings of reduced global communication capacity in autistic toddlers.…”

Organizational topology of brain and its relationship to ADHD in adolescents with d‐transposition of the great arteries

“…Differences in network topology have been seen in a variety of neurobehavioral disorders including schizophrenia and autism (Li et al. 2014; Griffa et al. 2015).…”

White Matter Diffusion of Major Fiber Tracts Implicated in Autism Spectrum Disorder

“…For example, reduced FA in ASD participants has been linked to increased ASD symptom severity and behaviors (Catani et al, 2008;Noriuchi et al, 2010;Poustka et al, 2012;Thakkar et al, 2008), as well as performance intellectual quotient (PIQ) (Alexander et al, 2007;Lange et al, 2010;Lee et al, 2009). In addition, alterations in FA in participants with ASD have been related to language abilities (Fletcher et al, 2010;Li et al, 2014;Mills et al, 2013), executive functions (Nair et al, 2015), and motor performance (Thompson et al, 2016). In developmental disorders such as ASD, DTI provides a unique opportunity to investigate the structural makeup and structural limits of functional communication in the brain.…”