This is Scientific American's 60 Second Science.

I'm Christopher Intagiato.

Certain concert venues like Boston Symphony Hall

are known to beautifully reflect the sounds of an orchestra.

And it turns out there's a similar process at play in your cochlea,

deep inside your ear,

where a tiny bony cavity houses the organ that allows you to hear.

It's like its own tiny little acoustic... the

acoustics chamber if you will.

So anything and everything you hear is going into your ear and then going into this

little bony chamber.

Mike Gordon, a psychologist at William Patterson University in New Jersey.

But while studying this process, he also found there's actually a lot of variability in the way people hear. Some frequencies can appear

tens of decibels louder or quieter than average based on the

resonant properties of a person's skull. We were shocked. My first version of

the draft had exclamation points all over the place, but we eventually remove those from the final copy.

First, Gordon's team gave 30 volunteers a hearing test, the standard type where a different frequencies of tones are played at varying loudness.

Then they did a bone conduction hearing test where vibrations are transmitted directly

onto the skull from behind the ear.

Finally, they projected white noise like this through the skull from behind

the ear and they recorded what came out at the forehead. This is that white noise filtered through Gordon's skull.

With those filtered samples, they were able to see the unique spectral fingerprints

...