Disorders of nasality in subjects with upper motor neuron type dysarthria following cerebrovascular accident.

The nasality of 19 subjects with upper motor neuron (UMN) damage following cerebrovascular accident (CVA), and 19 control subjects matched for age and sex, was investigated using both perceptual judgements of nasality and a modified version of the nasal accelerometric procedure described by Horii (1980). Nasality indices were calculated for each subject during the production of a series of nasal and non-nasal sounds, words, and sentences. Statistical comparison of the two groups revealed that the CVA subjects had significantly higher nasality indices on the production of nonnasal speech tasks than the controls. No significant difference was noted between the two groups on nasal tasks. Individual case by case examination of the accelerometer data confirmed the presence of hypernasality in 7 of the 19 CVA subjects. In contrast to the instrumental findings, the results of the perceptual judgements of nasality identified the presence of hypernasality, hyponasality, and normal nasal resonance within the CVA group.