Our Eyes and Ears Are Intimately Related

We don’t necessarily notice it, but having a conversation with a friend makes our brains work to process the information and make it meaningful.

Conversations in noisy environments, with people who speak another language or for people who have hearing loss all require more cognitive effort. For many years now, research in the field of hearing has focused on the listening effort needed for a hearing-impaired person to hold and understand a conversation in a noisy environment.¹ It’s been found that doing so requires a lot of effort and can cause fatigue, so much so that a hearing-impaired person might give up on a conversation in noise quickly because it requires so many cognitive resources.²

Surprisingly, eyes have proven to be a very useful tool for measuring listening effort. In fact, measurement of the pupil (pupillometry) is an involuntary way to measure listening effort.³ This technique uses an infrared camera. It measures the dilation of the pupil and compares it to a reference diameter to indicate the effort and focus that are needed to listen. Research has shown that the greater the listening effort, the more dilated the pupil.⁴ In other words, hearing-impaired people will have larger pupils when they’re trying to discern speech in noise.

Hearing aid manufacturers have found it relevant to show that their devices, in addition to improving speech understanding in noise, can reduce listening effort so that wearers can better enjoy conversations. When developing a new hearing aid technology, pupillometry was used to show that listening effort in noise can be reduced by 10% by wearing these hearing aids (compared to previous models).⁵
To learn more about this hearing aid technology, consult an audioprosthetist now.