Department of Communication Sciences and Disorders
100 Clinical Research Services
University of Houston
Houston, Texas 77204-6018

Phone: (713) 743-2897
Fax: (713) 743-2926  

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The faculty members in the Department of Communication Sciences and Disorders at the University of Houston conduct research on various areas of human communication and disorders. Their research investigates the speech, language, and hearing patterns of various populations. To learn more about each of our faculty's research programs, please read the information below and visit the individual faculty web pages. For specific information about research in our Department, please contact the faculty member or members whose research you are interested in.

Margaret Lehman Blake, Ph.D., CCC-SLP

Right Hemisphere Brain Damage (RHD)

Treatment for Language Processing Deficits in Adults with Right Brain Damage

In conjunction with Dr. Connie Tompkins at the University of Pittsburgh, we are conducting a Phase II study of a novel, implicit language treatment. The training is designed to target two language deficits observed in adults with RHD, namely a Coarse Coding deficit and a Suppression deficit.

Contextual Cues and Comprehension in Adults with Right Hemisphere Brain Damage

There is conflicting evidence regarding how well adults with RHD use contextual cues during comprehension processes. Current studies are systematically evaluating how these individuals use different types of contextual cues to facilitate comprehension.

Traumatic Brain Injury

My current research projects examine the idea of cognitive rest as part of management of sports concussion  and developing cognitive strategy training groups for veterans with mTBI related to blast-exposure.

View Dr. Blake's faculty profile »

Ferenc Bunta, Ph.D.

The core of Dr. Bunta's research is the study of bilingual and cross-linguistic phonological acquisition. There are multiple on-going projects that investigate various aspects of phonological acquisition and representation cross-linguistically and in bilingual speakers revolving around three main lines of research: 1. Phonological Accuracy and Whole-Word Measures in Bilingual and Monolingual Children, 2. Acoustic Properties of Bilingual Children’s Speech, and 3. Bi-Directional Markedness Phenomena in the Phonology of Bilingual Children.

Dr. Bunta and the Bilingual and Cross-Linguistic Language Laboratory at the University of Houston maintain active collaborations with various researchers and their laboratories locally and nationally.

View Dr. Bunta's faculty profile »

Stephanie Daniels, Ph.D., CCC-SLP

Dr. Daniels’ research is focused on understanding the neural underpinnings of swallowing as well as evidence-based evaluation and treatment of dysphagia in individuals with neurological disease. Recent funding through the Department of Veterans Affairs has facilitated identification of specific brain lesions associated with dysphagia in acute stroke patients. Current projects are focused on developing and validating a VA specific swallowing screening tool administered by nurses to identify risk of dysphagia in individuals with suspected stroke and to determine feasibility of implementation of such a tool in the emergency department.

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Martha Dunkelberger, Ph.D., CCC-SLP

Raising a Reader

An investigation of predictable outcomes of parent education on children in Head Start programs across the city of Houston. The interaction between phonological and literacy development and disorders.

COMD Learning Community

A program designed to improve at-risk students’ opportunities for success in college.  Successful Juniors and Seniors are trained to mentor Sophomore and Freshman students in COMD with focus on campus engagement, self-advocacy and executive function development.


View Dr. Dunkelberger's faculty profile »

Ashwini Joshi, Ph.D., CCC-SLP

Brain Control of Voice Production

The primary focus of Dr. Joshi’s research is to understand the role of the brain in voice production and the changes seen in the brain as a result of disordered voice and its treatment.


View Dr. Joshi's faculty profile

Lynn M. Maher, Ph.D., CCC-SLP

Dr. Maher’s research interests are in the area of brain-behavior relationships, specifically in the area of aphasia, an acquired language impairment secondary to stroke or other brain injury.  Over the past decade she has explored the application of principles of neuroplasticity to aphasia rehabilitation. This line of research began in collaboration with her mentor, Dr. Leslie Gonzalez Rothi at the University of Florida, and addressed the constructs of errorless learning in rehabilitation and the impact of use dependent learning using constraint induced language therapy (CILT) in individuals with chronic aphasia.  This line of research continues with a recent application to individuals in earlier phases of recovery. Other collaborations with colleagues at UT Medical School in Texas Medical Center utilizing magnetoencephalography (MEG) compared behavioral changes with changes in neural activity. In collaboration with Dr. Randi Martin from Rice University, Dr. Maher utilized inhibition training to facilitate word retrieval in aphasia.


View Dr. Maher's faculty profile »

Monica McHenry, Ph.D., CCC-SLP

Speech Research Laboratories

Dr. McHenry has three research labs, with a goal of being easily accessible to potential participants. The primary lab is located in the Clinical Research Services building, which also houses the Department of Communication Sciences and Disorders. This lab is equipped with equipment for acoustic, aerodynamic, and respiratory data acquisition and analysis. Here we conduct studies on factors impacting the effectiveness of vocal warm-up, including the impact of physical exercise. Research assistants also use this lab to analyze data from other studies.

A second lab is located in Dudley Hall, between the School of Music and the School of Theatre. The primary goal of this lab is to monitor performers’ voices to ensure vocal health. This lab is equipped with the Computerized Speech Laboratory (KayPentax) and Phonatory Aerodynamic System (KayPentax). We also assess hearing acuity and tonal discrimination. Monitoring programs are being constantly refined to determine the most discriminating variables that could indicate potential vocal problems. We also use this lab to assess singers’ vocal development over time. Doctoral of Music students use this lab as well, to explore the use of instrumentation in the development of professional voice.

A third lab is located at the Center for ENT, where we work in collaboration with Dr. Eric Powitzky. Here the focus is on determining the most effective treatment for individuals with organic voice disorders, such as unilateral vocal fold paralysis.

Singer training and development

We have just completed data acquisition on the first cohort of singers, having collected aerodynamic and acoustic data on incoming graduate and undergraduate students in the School of Music.  Preliminary analysis reveals that the efficiency of voice production improves with  training.  Because no differences were found over time in spoken sustained vowels, the protocol has been modified to include production of full voice sustained vowels for analysis of vibrato control.

The validity of self report of vocal effort

Researchers have suggested that vocal fatigue may become apparent through ratings of effort during high pitched soft phonation. A more sensitive indicator of vocal fatigue development may be phonatory threshold pressure, which reflects the amount of subglottal pressure required to initiate vocal fold vibration.  Preliminary correlations reveal no relationship between singers’ ratings of vocal effort and their phonatory threshold pressures.  This suggests that singers may be relatively unaware of the effort expended during singing.  Ratings of vocal effort over time revealed that singers who reported the most extensive voice use also reported the lowest effort ratings, potentially reflecting the perception that continuous talking and singing skews the perception of effort.

The effect of dopamine and deep brain stimulation (DBS) on the speech of individuals with PD

In collaboration with Albert Fenoy, MD, of the UT Medical School, we are investigating the speech production of individuals receiving various combinations of dopamine and deep brain stimulation.  We will compare vocal quality, phrasing, and intelligibility with dopamine only, DBS only, neither DBS nor dopamine, and both dopamine and DBS.

The impact of semi-occluded vocal tract exercises of vocal fold healing after surgery

In collaboration with Eric Powitzky, MD, and Leo Martinez, MD, of the Center for ENT, we are exploring strategies to improve vocal fold healing and to minimize scar tissue following surgery.  Patients with either open or closed wounds following vocal fold surgery are assigned either to a vocal rest group or a vocal rest plus semi-occluded vocal tract exercise group.  We speculate that mucosal vibration without collision forces will maintain the flexibility of the vocal fold mucosa during healing, as opposed to complete vocal rest.

Vocal warm-up with aerobic exercise:  effect of varying fitness levels

Previous work in our lab demonstrated that for some individuals, aerobic exercise, in addition to vocal warm-ups, was more effective in reducing phonatory threshold pressure than vocal warm-ups alone.  In the previous study, there was a confounding variable of physical fitness.  We are currently obtaining data comparing the effectiveness of these strategies in more and less physically fit men.

Components of vocal fatigue and potential preventative strategies

We are in the process of writing an NIH grant proposal to explore the components of vocal fatigue in singers.  Specifically, we will explore three contributors to fatigue:  central (mental), neuromuscular, and laryngeal tissue.  We will then introduce various preventative methods to determine if it is possible to delay the onset of fatigue during extensive rehearsals.

View Dr. McHenry's faculty profile »

Amber Thiessen, Ph.D., CCC-SLP

Augmentative and Alternative Communication (AAC)

Dr. Thiessen’s research focuses on creating effective augmentative and alternative communication (AAC) displays for adults with acquired brain injuries and other neurological conditions and improving treatment outcomes through communication partner/facilitator training. Her current research projects focus on measuring the visual attention patterns of adults with traumatic brain injury and aphasia when viewing grids and visual scene images.


View Dr. Thiessen's faculty profile