Efficiency in Magnocellular Processing: A Common Deficit in Neurodevelopmental Disorders

Frontiers in Human Neuroscience

David Philip Crewther¹  Alyse Christine Brown²  Carl Parsons³  Sheila Gillard Crewther⁴  Jessica Lee Peters⁴ 

[1] Centre for Human Psychopharmacology, Faculty of Health, Arts and Design, Swinburne University of Technology, Hawthorn, VIC, Australia;Medical Research Council, Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, United Kingdom;Port Philip Specialist School, Port Melbourne, VIC, Australia;School of Psychology and Public Health, La Trobe University, Melbourne, VIC, Australia;

关键词: magnocellular;    flicker fusion;    neurodevelopmental disorders;    visual processing;    autism spectrum disorder;    dyslexia;   

DOI  :  10.3389/fnhum.2020.00049

来源: DOAJ

【 摘 要 】

Several neurodevelopmental disorders (NDDs) including Developmental Dyslexia (DD), Autism Spectrum Disorder (ASD), but not Attention Deficit Hyperactive Disorder (ADHD), are reported to show deficits in global motion processing. Such behavioral deficits have been linked to a temporal processing deficiency. However, to date, there have been few studies assessing the temporal processing efficiency of the Magnocellular M pathways through temporal modulation. Hence, we measured achromatic flicker fusion thresholds at high and low contrast in nonselective samples of NDDs and neurotypicals (mean age 10, range 7–12 years, n = 71) individually, and group matched, for both chronological age and nonverbal intelligence. Autistic tendencies were also measured using the Autism-Spectrum Quotient questionnaire as high AQ scores have previously been associated with the greater physiological amplitude of M-generated nonlinearities. The NDD participants presented with singular or comorbid combinations of DD, ASD, and ADHD. The results showed that ASD and DD, including those with comorbid ADHD, demonstrated significantly lower flicker fusion thresholds (FFTs) than their matched controls. Participants with a singular diagnosis of ADHD did not differ from controls in the FFTs. Overall, the entire NDD plus control populations showed a significant negative correlation between FFT and AQ scores (r = −0.269, p < 0.02 n = 71). In conclusion, this study presents evidence showing that a temporally inefficient M pathway could be the unifying network at fault across the NDDs and particularly in ASD and DD diagnoses, but not in singular diagnosis of ADHD.

【 授权许可】

Unknown