Increased variability of stimulus-driven cortical responses is associated with genetic variability in children with and without dyslexia

• Published in: Developmental cognitive neuroscience 2018-11, Vol.34, p.7-17
• Main Authors: Centanni, T.M., Pantazis, D., Truong, D.T., Gruen, J.R., Gabrieli, J.D.E., Hogan, T.P.
• Format: Article
• Language: English
• Subjects: Auditory Cortex - physiology; Child; Dyslexia - genetics; Dyslexia - pathology; Female; gene; Humans; KIAA0319; Male; mechanisms; neural variability; Original Research; Reading; subgroups
• ISSN: 1878-9293; 1878-9307
• DOI: 10.1016/j.dcn.2018.05.008

•Quantified variability in evoked neural responses of children with and without dyslexia.•A subset of children with dyslexia had significantly higher variability in cortex.•Higher variability observed in auditory and visual domains in multiple reading network nodes.•Risk alleles in KIAA0319 were related to degree of variability in auditory cortex.•Results support unstable neural responses as a mechanism for some cases of dyslexia. Individuals with dyslexia exhibit increased brainstem variability in response to sound. It is unknown as to whether increased variability extends to neocortical regions associated with audition and reading, extends to visual stimuli, and whether increased variability characterizes all children with dyslexia or, instead, a specific subset of children. We evaluated the consistency of stimulus-evoked neural responses in children with (N = 20) or without dyslexia (N = 12) as measured by magnetoencephalography (MEG). Approximately half of the children with dyslexia had significantly higher levels of variability in cortical responses to both auditory and visual stimuli in multiple nodes of the reading network. There was a significant and positive relationship between the number of risk alleles at rs6935076 in the dyslexia-susceptibility gene KIAA0319 and the degree of neural variability in primary auditory cortex across all participants. This gene has been linked with neural variability in rodents and in typical readers. These findings indicate that unstable representations of auditory and visual stimuli in auditory and other reading-related neocortical regions are present in a subset of children with dyslexia and support the link between the gene KIAA0319 and the auditory neural variability across children with or without dyslexia.