Dysarthria associated with traumatic brain injury: Speaking rate and emphatic stress

Prosodic abnormality is common in the dysarthria associated with traumatic brain injury (TBI), and adjustments of speaking rate and emphatic stress are often used as steps in treating the speech disorder in patients with TBI-induced dysarthria. However, studies to date do not present a clear and detailed picture of how speaking rate and emphatic stress are affected in this speech disorder. This study, based on the acoustic analyses of syllable repetitions and sentence speech samples, reports on speaking rate and emphatic stress for 12 subjects with TBI and 8 healthy controls. For speaking rate, the subjects with TBI had (1) both slow speaking and articulation rates, (2) smaller phonation proportion and larger pause proportion, and (3) larger percentage change in speaking rate and smaller percentage change in articulation rate. For emphatic stress, the subjects with TBI had (1) significant increases in the difference and percentage change between pre-stressed and pre-unstressed pause durations, (2) significantly smaller difference between stressed and unstressed word durations, but not the percentage change between stressed and unstressed word durations, and (3) significantly reduced differences in f₀ movement and f₀ slope between stressed and unstressed words, but not in RMS range. This study demonstrates the multidimensional nature of prosodic deficits in the dysarthria related to TBI and illustrates the ability of acoustic measures to give a picture of the dysprosody related to TBI-induced dysarthria. Learning outcomes: As a result of this activity, the participant will be able to (1) describe the prosodic disturbances that have been reported in studies of dysarthria associated with TBI; (2) define acoustic measures appropriate to the analysis of changes in speaking rate and emphatic stress; and (3) discuss the importance of prosody to spoken communication.