Many adults report difficulties hearing in everyday situations, despite having hearing test results that are normal or near-normal. Now neuroscience researchers at UConn School of Medicine have developed a hearing test that can identify hearing loss or deficits in some individuals who are considered to have normal or near-normal hearing in traditional tests.

“We have a validated technique to identify ‘hidden’ hearing deficits that would likely go undetected with traditional audiograms,” said Leslie R. Bernstein, PhD, professor of neuroscience and surgery at UConn, who conducted the study with Constantine Trahiotis, emeritus professor of neuroscience and surgery. According to a recent announcement in UConn Today, their newly developed hearing test measures a person’s ability to detect binaural changes in sounds presented at levels of loudness that are close to those experienced in normal conversations.

The binaural system plays a fundamental and predominant role in the ability to localize sounds, to understand conversation in noisy places such as busy restaurants, and to attend to one of multiple, simultaneous sounds.

Professors Bernstein and Trahiotis

UConn neuroscience researchers Constantine Trahiotis, PhD, and Leslie R. Bernstein, PhD, in the Psychoacoustics Laboratory at UConn Health. (Photo: Janine Gelineau/UConn Health)

In developing their validated hearing test, the researchers studied 31 adults ages 30 to 67 with normal or near-normal audiograms. They found that listeners who have essentially normal clinical hearing test results may exhibit substantial deficits in binaural processing. The results of the study have been published in a November 2016 online edition of the Journal of the Acoustic Society of America.

“Our study shows that our novel binaural hearing test can help early identify vulnerable populations of listeners, and perhaps help determine when critical interventions are warranted,” said Trahiotis. Professors Bernstein and Trahiotis, who have been colleagues at UConn School of Medicine for 29 years, are considered to be at the forefront of binaural auditory research.

Bernstein notes that acquired hearing loss from excessive noise exposure has long been known to produce significant hearing deficits. The new research suggests that hearing loss may be even more widespread than was once thought. For example, experts in the hearing research field used to think that post-concert hearing loss or ear ringing was often only a temporary injury that would subside. But this new research and mounting evidence may change expert opinion.

Hearing problems pose substantial societal and economic problems for the approximately 15% of American adults who report some level of hearing loss. It is estimated that 360 million people worldwide have disabling hearing loss, with the World Health Organization (WHO) projecting that 1.1 billion teenagers and young adults are at risk of hearing loss due to the lingering effects of excessive noise from personal audio devices used with earbuds or headphones, and loud concerts.

“Greater understanding of normal hearing and the early detection of any underlying slight hearing deficits in supposed ‘normal’ listeners could help practitioners have a better chance of identifying ways to slow the progression of debilitating hearing loss in one’s lifetime, and even possibly finding future ways to restore it,” said Trahiotis.

The team’s research is funded through a $1.5 million grant by the Office of Naval Research. The US Navy has a keen interest in finding new ways to protect the hearing health of its workforce, some of whom are known to be at high risk of noise-induced hearing loss caused by exposure to excessively loud sounds.

Source: UConn Health, UConn Today

Image credits: Janine Gelineau, UConn Health; © Monkey Business Images | Dreamstime.com