Superior Temporal Gyrus, Language Function, and Autism

Abstract

Deficits in language are a core feature of autism. The superior temporal gyrus (STG) is involved in auditory processing, including language, but also has been implicated as a critical structure in social cognition. It was hypothesized that subjects with autism would display different size-function relationships between the STG and intellectual-language-based abilities when compared to controls. Intellectual ability was assessed by either the Wechsler Intelligence Scale for Children-Third Edition (WISC-III) or Wechsler Adult Intelligence Scale-Third Edition (WAIS-III), where three intellectual quotients (IQ) were computed: verbal (VIQ), performance (PIQ), and full-scale (FSIQ). Language ability was assessed by the Clinical Evaluation of Language Fundamentals-Third Edition (CELF-3), also divided into three index scores: receptive, expressive, and total. Seven to 19-year-old rigorously diagnosed subjects with autism (n = 30) were compared to controls (n = 39; 13 of whom had a deficit in reading) of similar age who were matched on education, PIQ, and head circumference. STG volumes were computed based on 1.5 Tesla magnetic resonance imaging (MRI). IQ and CELF-3 performance were highly interrelated regardless of whether subjects had autism or were controls. Both IQ and CELF-3 ability were positively correlated with STG in controls, but a different pattern was observed in subjects with autism. In controls, left STG gray matter was significantly (r = .42, p < or = .05) related to receptive language on the CELF-3; in contrast, a zero order correlation was found with autism. When plotted by age, potential differences in growth trajectories related to language development associated with STG were observed between controls and those subjects with autism. Taken together, these findings suggest a possible failure in left hemisphere lateralization of language function involving the STG in autism.

Neural Signatures of Autism Spectrum Disorders: Insights into Brain Network Dynamics

“…Few studies have related variations in brain structural abnormalities to specific phenotypes in autism, other than overall severity. In the language domain, Bigler et al (2007) found that superior temporal gyrus volume related to receptive language ability among typically developing children and adolescents but not those with autism, suggesting a breakdown in the structure-function relationship. In an early study, Pierce and Courchesne (2001) reported that cerebellar hypoplasia in children with ASD was correlated with the severity of repetitive behaviors.…”

Atypical functional lateralization of language in autism spectrum disorders

“…Structural and functional neuroimaging studies of language areas have provided evidence that differences in lateralization may underlie language and communication difficulties in individuals with ASD (Bigler et al, 2007;Boddaert et al, 2003;Chandana et al, 2005;Chiron et al, 1995;Flagg et al, 2005;Herbert et al, 2002;. For example, a series of volumetric studies by Herbert and colleagues (Herbert et al, 2002;, demonstrated that brain asymmetry patterns differed in children with high functioning autism compared to controls.…”

Immune transcriptome alterations in the temporal cortex of subjects with autism

“…Recent publications suggest a link between the volume of the superior temporal gyrus (STG) and language development in autistic children (Bigler et al, 2007). The superior temporal gyrus is involved in auditory processing, including language, and has also been implicated as a critical structure in social cognition (Baron-Cohen et al, 1999).…”