Why you go deaf to a sound you make yourself

A person sits at a piano and presses a key. The note sounds, and they barely register it. A second later someone else presses the same key, and the note seems suddenly louder. Nothing about the instrument changed between the two presses, and nothing about the room changed either. The difference is authorship. When the brain knows that a sound is coming from the body it is steering, it quietly turns the volume down before the sound even arrives, so your own footsteps, your own typing, and your own voice are all heard through a filter you never notice.

What everyone sees

What everyone sees is simple familiarity. People assume they ignore their own sounds because they are boring, or because attention has moved on to something more interesting. A person who does not flinch at their own footsteps looks relaxed; a person startled by someone else’s looks alert. The explanation seems to be about interest and expectation, not about perception itself. Nobody suspects that the sound arriving at the ear is being modified on the way in, and that the modification is calibrated to the body that produced it. The effect is invisible precisely because it is so well timed.

What is actually happening

The mechanism is called sensory attenuation, and it runs on a copy of the motor command known as corollary discharge or efference copy. When the brain issues a movement, it also sends a prediction of the sensory consequences to the relevant sensory areas, and that prediction is used to cancel the expected input. Sarah-Jayne Blakemore, Daniel Wolpert, and Chris Frith showed in a 1998 paper in Nature Neuroscience that self-produced tactile stimulation feels less intense than identical stimulation produced by another person, and that the effect depends on the prediction rather than on the sensation. The same logic applies to hearing. Studies of self-generated speech and of self-produced tones find that the evoked response in auditory cortex is smaller for self-produced sounds than for identical external ones, and that the size of the reduction tracks how predictable the sound is. When the prediction is experimentally distorted, the sound becomes louder again, which is the strongest evidence that the cancellation is predictive rather than merely attentional. The system is not muting the world; it is subtracting a forecast.

Why it stays hidden

It stays hidden because the filter is perfectly aligned with the body that owns it. You never hear the version of your own voice that other people hear, so there is no side-by-side comparison to notice. The mechanism also hides because it is adaptive rather than defective: a brain that could not discount its own footsteps would be flooded by the loudest, least informative signals in the room, which are the ones it is generating itself. The cost is that the calibration can drift. In schizophrenia research, weaker self-generated sound suppression has been linked to the experience of hearing one’s own inner speech as external, which is one reason the phenomenon is studied far beyond the laboratory. What feels like an absence of sound is really an act of subtraction.

How sensory attenuation shapes everyday hearing

The effect is easiest to observe with a recording of your own voice. Almost everyone finds it strange, thinner, and less familiar than the voice they hear while speaking, because the recording has not been passed through the predictive filter that normally accompanies speech production.

It also explains why a room full of people typing sounds louder when you stop typing, and why a phone call in a quiet office feels more intrusive than your own keyboard. The difference is not volume in the room; it is authorship of the sound.

The evidence in numbers and laboratory tests

Blakemore and colleagues used a robotic arm to deliver identical tactile stimulation either by the participant’s own movement or by the machine, and found that self-produced touch was rated as less intense and produced weaker brain responses. The design matters because the physical stimulus was held constant while only the sense of agency changed.

Auditory studies use the same logic. Participants hear a tone triggered by their own button press or by a computer, and the cortical response to the self-triggered tone is smaller. When the tone is delayed or altered, the suppression shrinks, showing that the brain is comparing the sound against a prediction rather than simply ignoring anything it caused.

When the mechanism misfires or fades

The suppression is not absolute. A self-produced sound that is unexpected, such as a wrong note on an instrument, is heard clearly because it violates the prediction, which is exactly why musicians notice their own mistakes so sharply.

In clinical research, reduced suppression of self-generated sounds has been associated with auditory verbal hallucinations, and the finding is contested in its details but widely replicated in direction. The mechanism is therefore both an everyday convenience and a window into how the brain decides what counts as the outside world.

Questions readers ask

Why does my own voice sound different on a recording?

Because while you speak, the brain predicts the sound of your own voice and partly cancels it. A recording bypasses that prediction, so you hear the raw signal that everyone else hears, which usually sounds thinner and less familiar.

What is corollary discharge?

It is a copy of the motor command that the brain sends to sensory areas when it issues a movement. The copy acts as a prediction of what the movement will feel or sound like, and it is used to cancel the expected sensory input.

Why do I not hear my own footsteps?

Because the brain predicts them from the walking movement and subtracts the expected sound. The footsteps still reach the ear, but the predicted component is cancelled, so they seem quiet or absent.

Is sensory attenuation the same as ignoring a sound?

No. Ignoring is a decision about attention. Sensory attenuation is a change in the sensory signal itself, driven by a prediction of what the body is about to produce, and it happens even when you are paying attention.