Perceptual analysis of speech disorders in progressive supranuclear palsy.

We used oral motor examinations and quantitative perceptual speech analysis to study deviant speech dimensions in 44 patients with progressive supranuclear palsy (PSP). All patients had dysarthria with variable degrees of spasticity, hypokinesia, and ataxia; 28 patients had all three of these components, and 16 patients had only two components. Twenty-two patients (50%) had predominantly spastic components, 15 (34%) had predominantly hypokinetic components, six (14%) had predominantly ataxic components, and in one (2%) the spastic, hypokinetic, and ataxic components were equal. Stuttering occurred in nine patients (20%) and palilalia in five (11%). The finding of a mixed dysarthria with a combination of spastic, hypokinetic, and ataxic components might assist in diagnosis and is consistent with the widespread neuropathologic changes found in PSP.