Abstract
Changes in speaking rate, maximum repetition rate (MRR), and nonspeech functions including swallowing and respiratory function were studied over time in two dysarthric patients with amyotrophic lateral sclerosis (ALS), from a point when speech intelligibility was still at a high level until oral communication became almost impossible. The following results were obtained.
1) Great declines in speaking rate and MRR were observed over time. In addition, both speaking rate and MRR were considerably slower as compared to the control group even when speech intelligibility was still high. The latter finding indicates these parameters are more sensitive in reflecting functional change in articulator, rather than speech intelligibility, at the early stage of the disease.
2) Speech dysfunction preceded swallowing dysfunction in occurrence, and apparent aspiration occurred at a monosyllable intelligibility level of approximately 30 to 40% in both patients.
These results were discussed in terms of assessment and management systems in ALS speakers.
