Speech Deterioration of Amyotrophic Lateral Sclerosis Before and After Diagnosis: A Case Study of a Newscaster

Abstract

Purpose This case study traced speech deterioration in an individual before and after the time of diagnosis of amyotrophic lateral sclerosis (ALS). Our participant was diagnosed with spinal-onset, familial ALS in 2017. The speaker's occupation, a professional newscaster for 37 years, allowed a retrospective examination of her speech during news segments over 37 months around the diagnosis, including prediagnosis. Method A total of 6 time points were selected to track auditory-perceptual and acoustic speech deterioration (2 years, 14 months, and 7 months prior to diagnosis; the month of diagnosis; and 7 months and 12 months after diagnosis). For perceptual ratings, 2 experts in motor speech disorders rated 17 speech dimensions on a 7-point scale. Four acoustic parameters were chosen for measurement: articulation rate, utterance duration, second formant frequency slope, and acoustic vowel space. Additionally, kinematic data were obtained from 1 time-point (8 months postdiagnosis) and descriptively compared to the movement of other individuals with ALS and to healthy speakers. Results As expected, both perceptual and acoustic results indicated a decline in the selected speech measures as the disease progressed. More interestingly, the measures showed a consistent curvilinear appearance in which the speech parameters exhibit an improvement until immediately before and around the diagnosis, followed by sudden, drastic deterioration. Kinematic results indicated a greater degree of movement and speed compared to healthy speakers, probably due to the speaker's occupation. Conclusions Based on the findings, the time around diagnosis is considered a critical period with respect to speech deterioration in ALS wherein a dynamic, increasing–decreasing pattern of changes occur. This finding appears to reflect the patient's compensatory strategies and the speech deficits associated with bulbar involvement.