Reading with one hemisphere.

The subjects of this study were 2 originally right-handed teen-aged girls who had undergone complete hemispherectomy (1 left, 1 right) for intractable epilepsy. Both subjects had developed normal language and reading capacities before the onset of their illness. The reading performance of H.P. (whose right hemisphere had been removed), while not as advanced in level as that of a normal 17-yr-old, showed no abnormality in any subcomponent of reading skill. The reading performance of N.I. (whose left hemisphere had been removed) was poor, but with a pattern of retained and impaired subskills strikingly similar to adult deep dyslexic patients and to split-brain patients given reading tasks lateralized to the left visual field (right hemisphere). The results are discussed with regard to implications for the reading capacity of the nondominant right hemisphere and also its putative contribution to normal reading.