Longitudinal Heschl's Gyrus Growth During Childhood and Adolescence in Typical Development and Autism

Abstract

Heightened auditory sensitivity and atypical processing of sounds by the brain are common in autism. Functional studies that measure brain activity suggest abnormal neural response to sounds, yet the development underlying atypical sound processing in autism is unknown. We examined the growth of the first cortical area of the brain to process sound, the primary auditory cortex, also known as Heschl’s gyrus. Volume of Heschl’s gyrus gray and white matter was measured using structural MRI in 40 children and adolescents with autism and 17 typically developing participants. Up to three time points of volumetric brain data, collected on average every 2.5 years, were examined from individuals 3-12 years of age at their first scan. Our study is the first to examine volumetric changes during childhood and adolescence in Heschl’s gyrus longitudinally, or in the same individuals over time. Consistent with previous studies using only one time point of data, no differences between the participant groups were found in Heschl’s gyrus gray matter volume. However, reduced longitudinal growth of Heschl’s gyrus gray matter volume was found in the right hemisphere in autism. Reduced longitudinal white matter growth in the left hemisphere was found in the right-handed autism participants. Atypical growth of Heschl’s gyrus white matter volume was found bilaterally in the autism individuals with a history of delayed onset of spoken language. Heightened reported sensitivity to sounds, obtained from the Sensory Profile, was associated with reduced gray matter volume growth in the right hemisphere. Our longitudinal analyses revealed dynamic gray and white matter changes in Heschl’s gyrus throughout childhood and adolescence in both typical development and autism.

Wide Range Achievement Test in Autism Spectrum Disorder: Test-Retest Stability

“…This study analyzed archival data obtained between 2006 and 2010 (see Prigge, Bigler, Fletcher, Zielinski, Ravichandran, Anderson, et al ., 2013; Travers, et al ., 2014). For the purpose of this study, the participants were 31 males diagnosed with autism spectrum disorder between the ages 6 and 22 years.…”

Mesial temporal lobe and memory function in autism spectrum disorder: An exploration of volumetric findings

“…No complications were encountered in the scanning process. Additional neuroimaging details previously have been published (see Prigge et al, 2013a; 2013b). …”

Brain imaging research in autism spectrum disorders

“…These brain regions are significantly over-reactive to sensory stimuli, even after individual differences in anxiety are controlled for. Different age-related changes in gray and white matter volumes in the Heschl’s gyrus are present [9]. Atypical sensory processing may be related to focal cortical dysplasias in ASD [10] and to atypical microstructure in the inferior longitudinal fasciculus and splenium of the corpus callosum [11].…”

“…When larger samples are examined using traditional volumetric and cortical thickness approaches, decreased growth of right Heschl’s gyrus gray matter [9], decreased occipital lobe cortical thickness [30], and increased volumetric growth of the caudate nucleus [34] and the brainstem [39 ▪ ] are reported. When regional cortical gray matter volumes are comprehensively examined from late childhood through young adulthood, more striking differences in ASD are found [27 ▪▪ ,39 ▪ ].…”

“…Tremendous biological complexity lies below what appear to be simple measures of brain structure and function [66–68]. Increased consideration of the clinical heterogeneity of ASD has led to characterizing individuals in imaging studies along quantitative dimensions of specific behaviors in addition to diagnosis and diagnostic algorithm scores [8,9,14]. The creation of large publically available ASD neuroimaging databases such as the Autism Brain Imaging Exchange (ABIDE) and the National Database for Autism Research (NDAR), support efforts to replicate results in independent samples [7,69 ▪ ,70].…”