Interdisciplinary Collaborations: Engineering

by Mary Spencer Aldridge

What does engineering have to do with communication sciences and disorders? Apparently, quite a bit. Two CSD faculty members, Dr. Gavin Bidelman and Dr. Miriam van Mersbergen, are collaborating with faculty from the University of Memphis Herff College of Engineering in their current research projects. CSD researchers are benefitting from the unique equipment, data analysis, and computer modeling techniques that Engineering faculty can offer. CSD researchers provide Engineering faculty with unique research questions and complex data sets that have distinctly practical applications.   

Dr. Gavin Bidelman, professor of audiology and director of the Auditory Cognitive Neuroscience Laboratory at the University of Memphis, has a background in engineering. He is interested in studying how the brain responds to speech, particularly in noisy conditions. The audiogram, which indicates the softest sounds a person can hear in a noiseless environment, is a poor predictor for how an individual can understand speech in a noisy environment. Dr. Bidelman’s team, along with Dr. Mohammed Yeasin of the Electrical Computer Engineering Department and Md Sultan Mahmud, a Ph.D graduate assistant in Agricultural and Biological Engineering use EEG scans to determine listener’s speech perception in a noisy environment.

Participants complete different perceptual tasks while an EEG recording is made. The information from the EEG recordings is coded into an algorithm developed by the engineering team. Dr. Bidelman and his team used the algorithm to predict if their participants had hearing loss. The audiograms of the participants are used to determine the accuracy of the classification algorithm. Currently, their technique is 80-90% accurate in predicting the presence of a hearing loss.

When asked why he thinks there is an overlap in the research interests of audiologists and engineers, Dr. Bidelman responded that findings in this study can be used in both fields in different ways. Engineers can use audiologic data to practice developing and applying big data science techniques. Big data science techniques developed by engineers can be used to help answer clinical questions in Audiology. Dr. Bidelman hopes to continue using EEG tests to measure various aspects of speech perception in the brain. In the future, he would like to see if mild cognitive impairment can be predicted by speech perception tasks and if the progression of dementia can be tracked using EEG signals.  

Dr. Miriam van Mersbergen, assistant professor of speech-language pathology and the director of the Voice Emotion and Cognition Laboratory at the University of Memphis, is also involved in interdisciplinary work that includes engineers. Her goal is to understand more about how air borne illnesses like COVID-19 are spread and why choir rehearsals and other singing events became super-spreader events during the pandemic.

Data collection requires that participants perform speech-related tasks inside a tent that was designed by lead engineer Dr. Jeff Marchetta and other members of the Mechanical Engineering department. A laser inside the tent illuminates the particles coming from the participant’s mouth and a high-speed camera records the movement of the illuminated particles. Experts in computer modeling were able to trace how far the particles traveled and made a computerized model based on the data.

According to Dr. van Mersbergen, this project is a great collaboration project for many fields like CSD, mechanical engineering, and otolaryngology because each group is interested in studying the trajectory of aerodynamics forces both inside and outside of the body and the physiologic processes behind it. The data collection techniques will provide insight into the contribution of lung function and speech context in the generation of particles that leave the mouth during speech and singing. The engineering models will identify how these particles behave once they leave the mouth. Together these analyses will identify which anatomical and physiological characteristics of speakers and singers may predispose them to becoming so-called super-emitters.

Ultimately, the researchers hope that the findings of this study will lead to more efficient recommendations to limit the spread of airborne diseases now and in the future. Researchers and students involved in this project are Dr. van Mersbergen, Dr. Jeff Marchetta, Dr. John Hochstein, Dr. Daniel Foti, Dr. Ranganathan Gopalakrishnan, Dr. Sandra Stinnett, Amy Nabors, Eric “Alan” Pillow, Chandler Cain, Brenda Hwang, Hayleigh Wilson, Miranda Fisher, and Sara Essaied.

A special thanks to Drs. Bidelman and van Mersbergen for discussing their projects!

Link to labs:

https://www.memphis.edu/acnl/ : Dr. Bidelman’s lab 

https://www.memphis.edu/vecl/ : Dr. Van Mersbergen’s lab