Reduced interhemispheric coherence in dyslexic adults

Cortex. 2010 Jun;46(6):794-8. doi: 10.1016/j.cortex.2009.09.006. Epub 2009 Sep 24.

Abstract

Introduction: Developmental dyslexia has been associated with reduced interhemispheric neural connectivity in children. The present study investigated functional interhemispheric connectivity in male dyslexic adults.

Methods: A group of 19 dyslexic men were compared to a group of 15 controls on interhemispheric coherence of the dominant frequency in the power spectrum during a visuo-spatial attention task. The coherence between a left hemisphere central-parietal electrode and the respective right hemisphere electrode and surrounding sites was analysed.

Results: Compared to controls, the dyslexic group demonstrated reduced, and more diffuse, interhemispheric coherence of alpha activity in the central-parietal cortex. No group differences in interhemispheric coherence were found on frontal, temporal or central sites.

Conclusions: The deviant pattern of functional connectivity in dyslexics is suggestive of an altered development of neural circuitry that may lead to deficits in magnocellular processing.

MeSH terms

  • Adult
  • Alpha Rhythm
  • Attention / physiology*
  • Brain / physiopathology*
  • Dyslexia / physiopathology*
  • Electroencephalography
  • Functional Laterality
  • Humans
  • Male
  • Middle Aged
  • Neuropsychological Tests
  • Space Perception / physiology*
  • Visual Perception / physiology*
  • Young Adult