Neuromotor speech deficits in children and adults with spina bifida and hydrocephalus.

Acquired cerebellar lesions are associated with motor speech deficits. Spina bifida with hydrocephalus (SBH) is a neurodevelopmental disorder that involves significant dysmorphology of the cerebellum. Videotaped narratives produced by 40 children and adults with SBH and their 40 age-matched controls were coded for three motor speech deficits: dysfluency, ataxic dysarthria (articulatory inaccuracy, prosodic excess, and phonatory-prosodic insufficiency) (Brown, Darley, & Aronson, 1970; Darley, Aronson, & Brown, 1969a), and speech rate. Individuals with SBH had more motor speech deficits than controls. Dysfluency was related to an interaction between chronological age and SBH. Speech rate was related independently to chronological age and SBH. Ataxic dysarthria was related to the biology of SBH, and was associated with both physical phenotype (level of spinal cord lesion) and medical history (number of shunt revisions). The data show that developmental as well as acquired lesions of the cerebellum disrupt motor speech, and add to the developmental role of the cerebellum in the automatization of motor skills, including speech.