Perceptuo-acoustic assessment of prosodic impairment in dysarthria

Dysprosody was studied in four groups of male subjects: subjects with amyot rophic lateral sclerosis (ALS) and mild intelligibility impairment, subject s with ALS and a more severe intelligibility loss, subjects with cerebellar disease, and neurologically normal controls. Dysprosody was assessed with perceptual ratings and acoustic measures pertaining to the regulation of du ration, f(0), and intensity within tone units of conversational samples. In telligibility reduction and prosodic disturbance were not necessarily equal ly impaired in all subjects, and it is concluded that these are complementa ry indices of severity of dysarthria. Compared to the neurologically normal control group, the clinical groups tended to decrease the overall duration of tone units, produce fewer words in a tone unit, and use smaller variati ons in f(0). Recommendations are offered for the assessement of prosody in dysarthria.