The effect of age, diagnosis, and their interaction on vertex-based measures of cortical thickness and surface area in autism spectrum disorder

Abstract

Autism spectrum disorder (ASD) is a lifelong neurodevelopmental condition that is accompanied by an atypical development of brain maturation. So far, brain development has mainly been studied during early childhood in ASD, and using measures of total or lobular brain volume. However, cortical volumetric measures are a product of two distinct biological neuroanatomical features, cortical thickness, and surface area, which most likely also have different neurodevelopmental trajectories in ASD. Here, we therefore examined age-related differences in cortical thickness and surface area in a cross-sectional sample of 77 male individuals with ASD ranging from 7 to 25 years of age, and 77 male neurotypical controls matched for age and FSIQ. Surface-based measures were analyzed using a general linear model (GLM) including linear, quadratic, and cubic age terms, as well as their interactions with the main effect of group. When controlling for the effects of age, individuals with ASD had spatially distributed reductions in cortical thickness relative to controls, particularly in fronto-temporal regions, and also showed significantly reduced surface area in the prefrontal cortex and the anterior temporal lobe. We also observed significant group × age interactions for both measures. However, while cortical thickness was best predicted by a quadratic age term, the neurodevelopmental trajectory for measures of surface area was mostly linear. Our findings suggest that ASD is accompanied by age-related and region-specific reductions in cortical thickness and surface area during childhood and early adulthood. Thus, differences in the neurodevelopmental trajectory of maturation for both measures need to be taken into account when interpreting between-group differences overall.

Neuroanatomical anomalies of dyslexia: Disambiguating the effects of disorder, performance, and maturation

“…Shaywitz, et al, 2007; Yeatman, et al, 2012). These interactions further suggest that, similar to other neurodevelopmental disorders such as attention deficit hyperactivity disorder and autism (Ecker, et al, 2014; Shaw, et al, 2007), dyslexia might also be characterized by atypical developmental trajectory of specific brain areas.…”

Can we predict subject‐specific dynamic cortical thickness maps during infancy from birth?

“…Cortical thickness is a rich attribute that has the potential to help identify early postnatal neurodevelopmental disorders (Ecker et al, 2014; Querbes et al, 2009; Singh et al, 2008). To overcome the need of additional MRI scans later on for individual assessment of cortical thickness changes, we proposed a generic prediction framework for any cortical attributes from single or multiple time point(s).…”

Identification of a Common Neurobiological Substrate for Mental Illness

“…4 Additionally, while autism spectrum disorders present symptoms throughout the lifespan, they typically first present very early in life and are associated with altered developmental trajectories of brain structure, 18–20 which may furthermore interact with key features of the diagnosis (eg, as indicated by IQ). 18,19 In light of this, and the fact that the 10 VBM studies we identified of adults with autism spectrum disorders largely did not address this heterogeneity, we opted to exclude autism to maximize interpretability of our results. Studies in which some patients were younger than age 18 years were included so that for the diagnoses selected all available studies were included.…”