Hemispherectomy (disconnection or removal of an entire cerebral hemisphere) is a rare
surgical procedure used for the relief of
drug-resistant epilepsy in children. After
hemispherectomy, contralateral
hemiplegia persists whereas gross expressive and receptive language functions can be remarkably spared. Motor speech deficits have rarely been examined systematically, thus limiting the accuracy of postoperative prognosis. We describe the speech profiles of hemispherectomized participants characterizing their intelligibility, articulation, phonological speech errors, dysarthric features, and execution and sequencing of orofacial speech and non-speech movements. Thirteen participants who had undergone
hemispherectomy (six left, seven right; nine with congenital, four with acquired
hemiplegia; operated between four months and 13 years) were investigated. Results showed that all participants were intelligible but showed a mild dysarthric profile characterized by neuromuscular asymmetry and reduced quality and coordination of movements, features that are characteristic of adult-onset unilateral upper motor neuron
dysarthria, flaccid-ataxic variant. In addition, one left and four right
hemispherectomy cases presented with impaired production of speech and non-speech sequences. No participant showed evidence of verbal or
oral dyspraxia. It is concluded that mild
dysarthria is persistent after left or right
hemispherectomy, irrespective of age at onset of
hemiplegia. These results indicate incomplete functional re-organization for the control of fine speech motor movements throughout childhood, and provide no evidence of hemispheric differences.