Toward the Origins of Dyslexia

A series of experiments will be reported comparing the performance of groups of 11 year old and 15 year old children with dyslexia with groups of normal children matched for chronological age (CA) and reading age (RA) respectively. Experiments testing gross motor skill demonstrated that both groups of children with dyslexia showed significant deficits in balance when required to undertake a further task at the same time, whereas the control groups were not affected. It was concluded that the control children balanced automatically whereas the children with dyslexia did not. Further experiments indicated that working memory performance was not disordered, in that deficits in memory span were paralleled by deficits in speed of articulation. Tests of information processing speed led to an interesting dissociation. Simple reaction performance was indistinguishable from that of the CA controls. By contrast, on the simplest possible choice reaction, both groups of children with dyslexia were..