Nasal airflows in parkinsonian speakers

Velopharyngeal control in individuals with Parkinson's disease (PD) was studied by obtaining rates of nasal airflow during syllable repetitions. Nasal airflows were described with respect to disease progression, phonetic context, and speaking rate. Significant differences in nasal airflows were obtained for disease progression and phonetic context. The data suggested that velopharyngeal control deteriorates systematically with disease progression. Parkinson's patients at mild and moderate levels of disease progression differentiated the nasal consonant from the oral consonants with increased nasal airflow associated with the nasal consonant. Differences, while not significant, were also observed in nasal flow rate values when the PD patients increased speaking rate from 1 to 5 syllables per second.