Eye-Eardrum Signal Mystery

When you move your eyes, your eardrums also move, bulging in the opposite direction and vibrating slightly even when there is no sound. Scientists discovered this phenomenon in 2018 by placing sensitive microphones in people’s ears and tracking the tiny movements. Even more strangely, the eardrums start moving about 10 milliseconds before the eyes actually move, which means they are not reacting to vision but to a signal sent by the brain in advance. Researchers think this may help the brain align what we see with what we hear, but they still do not know the exact purpose or mechanism behind it.

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