Enhancement of brain event-related potentials to speech sounds is associated with compensated reading skills in dyslexic children with familial risk for dyslexia.

Autor: Lohvansuu K; Department of Psychology, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland. Electronic address: kaisa.lohvansuu@jyu.fi., Hämäläinen JA; Department of Psychology, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland., Tanskanen A; Department of Psychology, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland., Ervast L; Logopedics and Child Language Research Centre, Faculty of Humanities, University of Oulu, P.O. Box 1000, FI-90014 University of Oulu, Finland; Department of Clinical Neurophysiology, Neurocognitive Unit, Oulu University Hospital, P.O. Box 50, FI-90029 Oulu University Hospital, Finland., Heikkinen E; Logopedics and Child Language Research Centre, Faculty of Humanities, University of Oulu, P.O. Box 1000, FI-90014 University of Oulu, Finland; Department of Clinical Neurophysiology, Neurocognitive Unit, Oulu University Hospital, P.O. Box 50, FI-90029 Oulu University Hospital, Finland., Lyytinen H; Department of Psychology, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland., Leppänen PH; Department of Psychology, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland.
Jazyk: angličtina
Zdroj: International journal of psychophysiology : official journal of the International Organization of Psychophysiology [Int J Psychophysiol] 2014 Dec; Vol. 94 (3), pp. 298-310. Date of Electronic Publication: 2014 Oct 12.
DOI: 10.1016/j.ijpsycho.2014.10.002
Abstrakt: Specific reading disability, dyslexia, is a prevalent and heritable disorder impairing reading acquisition characterized by a phonological deficit. However, the underlying mechanism of how the impaired phonological processing mediates resulting dyslexia or reading disabilities remains still unclear. Using ERPs we studied speech sound processing of 30 dyslexic children with familial risk for dyslexia, 51 typically reading children with familial risk for dyslexia, and 58 typically reading control children. We found enhanced brain responses to shortening of a phonemic length in pseudo-words (/at:a/ vs. /ata/) in dyslexic children with familial risk as compared to other groups. The enhanced brain responses were associated with better performance in behavioral phonemic length discrimination task, as well as with better reading and writing accuracy. Source analyses revealed that the brain responses of sub-group of dyslexic children with largest responses originated from a more posterior area of the right temporal cortex as compared to the responses of the other participants. This is the first electrophysiological evidence for a possible compensatory speech perception mechanism in dyslexia. The best readers within the dyslexic group have probably developed alternative strategies which employ compensatory mechanisms substituting their possible earlier deficit in phonological processing and might therefore be able to perform better in phonemic length discrimination and reading and writing accuracy tasks. However, we speculate that for reading fluency compensatory mechanisms are not that easily built and dyslexic children remain slow readers during their adult life.
(Copyright © 2014 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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