Latest Research Examines Hearing Protection and Perception

A cellphone ringing, a siren approaching, a gunshot sounding in the distance. We depend on our hearing in many dynamic situations to make informed decisions about our surroundings. People working in the armed forces, construction, and public safety, however, depend on their sense of hearing to stay alive.

According to the Centers for Disease Control and Prevention, veterans are 30 percent more likely to have severe hearing loss than the general population.

“Hearing loss and tinnitus represent the largest injuries in terms of money spent for the U.S. military, in terms of money spent. For over 3 million affected service members, over a billion dollars per year are spent on medicines, tinnitus therapy, hearing aids, surgery or other medical care,” said College of Engineering researcher and John Grado Endowed Professor John Casali.

The challenge is this: Soldiers, first responders, and construction and industrial workers need to hear sounds from all directions to detect threats, hear warning signals, and communicate with co-workers. At the same time, the delicate neural structure of the inner ear needs to be protected from loud sounds such as gunfire. Hearing is always “on” and omnidirectional, unlike vision, which requires focus. When hearing is injured or impaired, its value to human functioning becomes evident.

“When your life depends on your hearing, and your hearing depends on your hearing protection, auditory situational awareness presents a conundrum.” Casali said. “When people lose their auditory situational awareness, they are often compromised in their work and as a result may not be able to continue in certain mission operation specialties.”

Casali and researchers in the Grado Department of Industrial and Systems Engineering (ISE)  have made significant strides in improving hearing protection and situational awareness for military personnel through the development of a groundbreaking training system. The Portable Auditory Localization Awareness Training (PALAT) system thoroughly tests military-grade hearing protectors to see how they impact a soldier’s ability to detect, recognize and localize sound, as compared to the open, natural ear.

A compact, portable training tool, the PALAT system can be set up in an office environment, barracks, or other military-training locales. The fold-up style and size were designed so subjects could easily and efficiently perform the headset training. It also provides trainees with an immediate, objective score for their performance, compares them with other trainees, and adapts to their performance to provide additional training as needed. Involving a diverse team of researchers over the course of 11 years, the final PALAT prototype was developed entirely at Virginia Tech.

Article originally appeared on Virginia Tech News.