Variability in upper motor neurone-type dysarthria: an examination of five cases with dysarthria following...

The degree of diversity in the nature and extent of the physiological deficits which occur in subjects with dysarthria with similar neurological damage is demonstrated through the individual assessment profiles of five subjects with dysarthria following upper motor neurone (UMN) damage. The perceptual profiles of each subject were compiled using perceptual ratings of deviant speech parameters, intelligibility ratings from the Assessment of Intelligibility of Dysarthric Speech (ASSIDS), and perceptual judgements of subsystem function determined from the Frenchay Dysarthria Assessment (FDA). For each individual, the perceptual profile of their speech impairments was compared and contrasted with the objective results of spirometric and kinematic assessments of respiratory function aerodynamic and electroglottographic evaluations of laryngeal function, pressure and strain gauge evaluations of articulatory function, and nasal accelerometric assessments of nasality. The outcomes of the individual perceptual and physiological profiles are discussed with respect to the presence of differential subsystem impairments both within each subject and between subjects with similar underlying pathophysiological deficits. The importance of interpreting the instrumental findings with respect to the interdependency of each of the motor speech subsystems, the limitations of perceptual assessments, and the advantages of utilising both perceptual and physiological analyses in the process of identifying treatment goals is discussed.