Date of Award


Degree Type


Degree Name

Master of Science in Speech-Language Pathology


Communicative Disorders

First Advisor

Leslie Mahle r


Objective: This study investigated the impact of an intensive articulation treatment on acoustic and perceptual measures of speech in an individual with spastic dysarthria acquired from a traumatic brain injury (TBI).

Method: A single-subject A-B-A-A experimental design was used to measure the effects of an intensive articulation treatment that incorporated principles of motor learning to evaluate the impact on speech and communication. The primary dependent variables were single word intelligibility and vowel space area. Additional dependent variables included vocal sound pressure level (dB SPL) during a variety of speech tasks, acoustic measures of voice, and listener perceptual ratings of voice quality and speech.

Results: Multiple comparisons with t-tests were used to determine statistically significant changes in primary and secondary dependent variables. Statistically significant (p<0.05) changes were present immediately post-treatment with single word intelligibility (p=0.00), vowel prolongation duration (p=0.00), and lip pressure exerted (0.04) and six months following treatment with vowel duration prolongation (p=0.01) and Noise-to-Harmonics Ratio (p=0.02). There were no statistically significant (p<0.05) changes with listener preference studies, vowel space area, and vocal dB SPL across vowel prolongation and speech tasks immediately post-treatment and six months following treatment.

Conclusions: These data demonstrate that this individual with spastic dysarthria secondary to a traumatic brain injury responded positively to an intensive articulation treatment on selected variables, particularly on tasks practiced directly in treatment. Generalization of a treatment effect outside of treatment was not demonstrated. Further research is needed to determine whether the lack of generalization was due to the treatment or specific characteristics of the individuals who are treated.

Keywords: Traumatic Brain Injury, dysarthria, articulation, motor learning, speech disorder, speech treatment, behavioral treatment



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