Science

As our eyes move, so do our eardrums

As our eyes move, so do our ea...
There's a previously unobserved link between our eyes and our ears
There's a previously unobserved link between our eyes and our ears
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There's a previously unobserved link between our eyes and our ears
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There's a previously unobserved link between our eyes and our ears

According to a recent study from North Carolina's Duke University, moving our eyes causes our eardrums to move, too. The scientists say that the finding may lead to a new understanding of hearing disorders, such as the difficulty that some people have with following a conversation in a crowded room.

Led by Prof. Jennifer Groh, the research team got 16 test subjects to sit in a darkened room and follow shifting LEDs with their eyes, without moving their heads. Those people also had tiny microphones placed in their ear canals, which were so sensitive that they could detect the vibrations made by the eardrums as they move back and forth.

It was found that as the peoples' eyes moved left or right, the eardrums correspondingly pointed in that same direction, with one side bulging inward at the same time the other side bulged outward. The larger the eye movement, the more pronounced the movement of the eardrums.

Interestingly, the eardrum vibrations actually started slightly before the eye movements. The researchers believe that this is because the motions of both the ears and the eyes are controlled by the same motor commands deep within the brain.

"The fact that these eardrum movements are encoding spatial information about eye movements means that they may be useful for helping our brains merge visual and auditory space," says David Murphy, a doctoral student in Groh's lab. "It could also signify a marker of a healthy interaction between the auditory and visual systems."

A paper on the research was recently published in the journal Proceedings of the National Academy of Sciences.

Source: Duke University

4 comments
amazed W1
If you ride a bike in traffic like London's or NY's you will have found that as you get used to the traffic your eyes look forward and your ears look "backwards" and your brain processes the combined data into a circular moving map, and does so sufficiently for those dangerous backwards glances to become rarely needed. This is not the same effcet as the Dukes University experiment has monitored but it does illustrate how your brain adapts reactions to different inputs, and I'm still alive!.
Sharwan Kumar
I suggest to the authors or whoever is interested in doing that: 1 Investigate the relation between the auditory and the visible stimuli in patients who suffer from tinnitus as that can prove of great benefit in alleviating their suffering. 2 Studying the relation between the auditory and the visible stimuli during rapid eye movement sleep can go a long way in helping people get a good sleep.
Kpar
I would like to hear more about the link between this discovery and difficulty in hearing conversations in a crowded, noisy environment. I have always suffered from this, despite quite acute hearing sensitivity for my age, and recently found out my mother has had the same issue for her entire life, positing a genetic influence. amazedW1 raises an interesting point- our brains (obviously) have multiple inputs being processed simultaneously all the time- clearly a survival factor. Vision is highly directional- particularly central vision- while hearing is much more omni-directional- bringing information to the brain so it can focus on oncoming threats or objects of interest- a global picture is established in the brain.
IvanWashington
I long have felt something deep in my ear move whenever I swivel my eyes.