Variability in the perceptual and physiological features of dysarthria following severe closed head injury: an examination of five cases.

The perceptual and physiological features of the dysarthric speech of five severely closed-head-injured (CHI) subjects were examined in a case-by-case analysis. The five male CHI subjects included in the study were selected to reflect the range of severity and types of dysarthria evident in the CHI population. The perceptual profiles of each subject consisted of the findings of a perceptual speech analysis, the Frenchay Dysarthria Assessment (FDA) and the Assessment of the Intelligibility of Dysarthric Speakers (ASSIDS). The subjects' physiological profiles included the results of instrumental assessments of the respiratory, laryngeal, velopharyngeal and articulatory subsystems of the speech-production mechanism. The case studies highlighted the variability among the individual subjects with respect to the location, physiological nature, and severity of impairment in their speech-production mechanisms. In addition, the interdependence of the various speech subsystems in determining speech outcome, the presence of differential subsystem impairment in dysarthria following CHI, and the varied therapeutic requirements of the individual subjects were identified. Clinically, the case studies highlighted the importance of developing individual treatment programmes based on comprehensive perceptual and physiological evaluations of the speech mechanism in each CHI subject with dysarthric speech.