1. Bayliss AP, Kritikos A. {{Brief Report: Perceptual Load and the Autism Spectrum in Typically Developed Individuals}}. {J Autism Dev Disord}. 2010 Dec 28.
A fundamental task of the cognitive system is to prioritize behaviourally relevant sensory inputs for processing at the expense of irrelevant inputs. In a study of neurotypical participants (n = 179), we utilized a brief flanker interference task while varying the perceptual load of the visual display. Typically, increasing perceptual load (i.e., with greater numbers of search items) reduces interference from a competing peripheral distractor. We show that individuals who score above average on the Autism Spectrum Quotient (AQ) show stronger interference at high perceptual load than individuals with below-average AQ scores. This is consistent with recent findings in individuals with autism spectrum conditions, and supports the idea that the cognitive style of the autistic brain is reflected in a broader phenotype across the population.
2. Bernardi S, Anagnostou E, Shen J, Kolevzon A, Buxbaum JD, Hollander E, et al. {{In vivo (1)H-magnetic resonance spectroscopy study of the attentional networks in autism}}. {Brain Res}. 2010 Dec 22.
Attentional dysfunction is one of the most consistent findings in individuals with autism spectrum disorders (ASD). However, the significance of such findings for the pathophysiology of autism is unclear. In this study, we investigated cellular neurochemistry with proton magnetic resonance spectroscopy imaging ((1)H-MRS) in brain regions associated with networks subserving alerting, orienting, and executive control of attention in patients with ASD. Concentrations of cerebral N-acetyl-aspartate (NAA), creatinine+phosphocreatinine, choline-containing compounds, myo-inositol (Ins) and glutamate+glutamine (Glx) were determined by 3T (1)H-MRS examinations in 14 high-functioning medication-free adults with a diagnosis of ASD and 14 age- and IQ-matched healthy controls (HC) in the anterior cingulate cortex (ACC), thalamus, temporoparietal junction (TPJ), and areas near or along the intraparietal sulcus (IPS). Compared to HC group, the ASD group showed significantly lower Glx concentrations in right ACC and reduced Ins in left TPJ. This study provides evidence of abnormalities in neurotransmission related to networks subserving executive control and alerting of attention, functions which have been previously implicated in ASD pathogenesis.
