An MRI and proton spectroscopy study of the thalamus in children with autism

Abstract

Thalamic alterations have been reported in autism but the relationships between these abnormalities and clinical symptoms, specifically sensory features, have not been elucidated. The goal of this investigation is to combine two neuroimaging methods to examine further the pathophysiology of thalamic anomalies in autism and to identify any association with sensory deficits. Structural MRI and multi-voxel, short echo-time proton magnetic resonance spectroscopy ( 1 H MRS) measurements were collected from 18 male children with autism and 16 healthy children. Anatomical measurements of thalamic nuclei and absolute concentration levels of key 1 H MRS metabolites were obtained. Sensory abnormalities were assessed using a sensory profile questionnaire. Lower levels of NAcetylaspartate (NAA), phosphocreatine and creatine, and choline-containing metabolites were observed on the left side in the autism group when compared to controls. No differences in thalamic volumes were observed between the two groups. Relationships, although limited, were observed between measures of sensory abnormalities and 1 H MRS metabolites. Findings from this study support the role of the thalamus in the pathophysiology of autism and more specifically in the sensory abnormalities observed in this disorder. Further investigations of this structure are warranted, since it plays an important role in information processing as part of the cortico-thalamo-cortical pathways.

Measuring neural excitation and inhibition in autism: Different approaches, different findings and different interpretations

“…However, other studies have found decreased glutamate/Glx in ASD in regions including the ACC (Bernardi et al, 2011;van Elst, Maier, Fangmeier, & Endres, 2014) the basal ganglia (Horder et al, 2013); frontal and occipital cortex, the cerebellum (Devito et al, 2007) and white matter (Corrigan et al, 2013). Yet other studies have found no significant differences in glutamate / Glx levels between individuals with and without ASD in several different brain regions including parietal lobes (Horder et al, 2013;Page et al, 2006), frontal lobes (Horder et al, 2013) temporal lobes (Devito et al, 2007), and occipital lobes (Robertson, Ratai, & Kanwisher, 2015); the thalamus (Bernardi et al, 2011;Doyle-Thomas et al, 2014;Hardan et al, 2008); hippocampus (Joshi et al, 2012);and cerebellum (van Elst et al, 2014). Therefore, the literature regarding glutamate/Glx levels in ASD is mixed.…”

Mitochondrial Dysfunction in Autism Spectrum Disorders

“…NAA is an important brain metabolite and a marker for mitochondrial dysfunction [14][15][16] since it is synthesised solely by neuronal mitochondria and one of its main functions includes contributing to the production of energy by mitochondria. Reduced NAA concentrations were also reported in a study conducted by Friedman et al Friedman et al in a group of 45 children with ASD, 13 typically developing (TD) controls and 15 children with development delay reported reduced in the ASD group in comparison to the controls [17].…”

“…Goldenthal et al reported reduced NAA, phosphocreatine and creatine levels in the left thalamus of children with autism [16]. Phosphocreatine and creatine provide information about cellular energy metabolism that have a particularly important role in tissues with high fluctuating energy demands.…”

Involvement of Neuroinflammation during Brain Development in Social Cognitive Deficits in Autism Spectrum Disorder and Schizophrenia

“…Both auditory and visual stimuli from peripheral organs are sent to the thalamus, and then to the primary auditory or visual area in the cerebral cortex (Tamietto and de Gelder, 2010;Hackett, 2015). Functions of the thalamus are impaired in ASD schoolchildren, adolescents, and adults (Hardan et al, 2008;Lai et al, 2010). Significant decreases in cerebellar activity and cerebellum-thalamus connectivity are induced in a light or mild motor performance such as 20 finger taps for each hand in ASD schoolchildren (Mostofsky et al, 2009).…”