Thesis Title

Auditory Evoked Potentials in Speakers With Apraxia of Speech

Date of Graduation

Spring 2004


Master of Science in Communication Sciences and Disorders


Communication Sciences and Disorders

Committee Chair

Cynthia McCormick


The purpose of the current study was to build upon previous research that investigated auditory processing skills of persons with apraxia of speech (AOS) and document the activation of cortical levels of the auditory system as measured through auditory P300 event-related potentials. AOS is categorized as a sensory motor speech deficit. However, current treatment approaches focus on motoric techniques and have not proven effective for generalization purposes. Preliminary auditory testing was completed prior to event-related potential testing. This included otoscopy, tympanometry, distortion product otoacoustic emissions, pure tone audiometry, and auditory brainstem response testing. P300 waveforms were obtained to examine participants' auditory processing skills. Specific areas of interest included waveform latency and amplitude differences between the control group (two speakers without AOS) and the experimental group (two speakers with AOS and aphasia). These differences were measured using tonal stimuli (1000 Hz/2000 Hz) and consonant-vowel (CV) units (di/da and ga/da) in odd-ball paradigms. Hemispheric differences were documented. Due to the small number of participants, statistical analyses were not possible; however, descriptive differences were discussed. The tonal test condition produced a P300 in all participants, while the di/da CV test condition produced a P300 in only one control participant. Although all participants responded to the odd-ball stimuli (finger raise), not all generated a P300 in all test conditions. These preliminary data revealed the necessity for further research in this area.


apraxia of speech, auditory P300, auditory evoked potentials, cognitive processing, auditory feedback

Subject Categories

Communication Sciences and Disorders


© Shelby A. Dellheim