On the search for better hearing diagnostics using brain signals

On the search for better hearing diagnostics using brain signals

tirsdag 04 maj 21
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Kontakt

Gerard Encina-Llamas
Postdoc
DTU Sundhedsteknologi
45 25 39 66

Kontakt

Torsten Dau
Sektionsleder, Professor
DTU Sundhedsteknologi
45 25 39 77

Kontakt

Bastian Epp
Lektor
DTU Sundhedsteknologi
45 25 39 53

Researchers from DTU Health Tech investigated whether a fundamental property of a healthy cochlea, which is relevant for improved diagnostics, can be assessed using brain signals.

You may have experienced that, in order to evaluate your hearing, an audiologist or an ear doctor has performed a simple test called audiometry on you. The test included brief beeps at different frequencies, and your task was to press a button whenever you heard the beep. Even though audiometry is very informative, some hearing damage remains undetected by this test. In this study, we propose to use a type of brain signal named envelope following response to assess a particular property of cochlear function. An altered cochlear response as reflected in the recorded brain signal would indicate that specific cells in the cochlea are damaged and dysfunctional. Hence, assessing such a cochlear property could be used to disentangle damage to different types of cells in the cochlea, and thus lead to a more precise diagnostic of hearing impairment.

Computational simulations change the result

Postdoc Gerard Encina-Llamas, who is part of the Hearing Systems section at DTU Health Tech, have recorded brain signals in normal-hearing and hearing-impaired listeners, together with Professor Torsten Dau and Associate Professor Bastian Epp. Analysis of the collected data suggested that this particular property of cochlear function could indeed be estimated from the recorded brain signals. However, the final conclusion of the study dismisses these initial findings.

So why is that? Apart from recording brain signals experimentally, the authors behind the study did something else that is not extensively done in hearing research yet. They used a computational model of the auditory system to simulate these brain signals. The simulations revealed that what was being estimated from the brain signals was not the particular property of cochlear function under investigation, but something else that coincidentally resembled in shape and value to it. Therefore, the answer is, no, it is not possible to assess such fundamental property of a healthy cochlea through this type of brain signals.

"This interdisciplinary multi-method approach is becoming more common in hearing research, and we must continue this way."
Postdoc Gerard Encina-Llamas

Interdisciplinary multi-method approaches are the way forward

Gerard Encina-Llamas concludes: ”Our paper shows that investigating the same question using different methods increases the probability of achieving the right conclusion. In our case, if we had not performed the computer model simulations, we would have reported an incorrect conclusion. This interdisciplinary multi-method approach is becoming more common in hearing research, and we must continue this way.”

You can read the full scientific paper in Scientific Reports for more details.

(Top image: Colourbox)

https://www.food.dtu.dk/nyheder/Nyhed?id=%7BE160FF2D-5E17-4B78-875E-C2462B223BEE%7D
13 MAJ 2021