Brain-potential analysis of visual word recognition in dyslexics and typically reading children

Front Hum Neurosci. 2014 Jun 30:8:474. doi: 10.3389/fnhum.2014.00474. eCollection 2014.

Abstract

The specialization of visual brain areas for fast processing of printed words plays an important role in the acquisition of reading skills. Dysregulation of these areas may be among the deficits underlying developmental dyslexia. The present study examines the specificity of word activation in dyslexic children in 3rd grade by comparing early components of brain potentials elicited by visually presented words vs. strings of meaningless letter-like symbols. Results showed a more pronounced N1 component for words compared to symbols for both groups. The dyslexic group revealed larger left-lateralized, word-specific N1 responses than the typically reading group. Furthermore, positive correlations between N1 amplitudes and reading fluency were found in the dyslexic group. Our results support the notion of N1 as a sensitive index of visual word processing involved in reading fluency.

Keywords: N1; developmental dyslexia; event-related potentials; reading fluency; visual attention; visual word recognition.