Comunicación entre los hemisferios cerebrales en lectores adultos disléxicos y experimentados

Abstract

It has often been suggested that problems of communication between the cerebral hemispheres are part of the profile of impairments in dyslexia. Henderson, Barca and Ellis (2007) obtained evidence in support of that suggestion in a study which compared the bilateral advantage. in adult dyslexics and good readers. The term bilateral advantage. refers to the fact that if two copies of the same word are presented very briefly, one to the left of a central fixation point and one to the right, good adult readers identify the word more efficiently than if only a single copy is presented to the left or right of fixation. The bilateral advantage is thought to depend on effective and rapid communication of visual information between the hemispheres across the corpus callosum. Henderson, et al. (2007) found that adult dyslexics do not show a bilateral advantage and concluded that inter hemispheric communication of visual information about words is indeed impaired in adult dyslexics. Additional experiments provided further insights into the precise nature of the dyslexic deficit. Those findings, and the wider literature on inter hemispheric communication and the bilateral advantage, are discussed. The possible consequences of impaired callosal transfer of visual information on reading are also considered. © 2009 AELFA y Grupo Ars XXI de Comunicación, S.L.