When sound waves from the outside world -- someone else's voice, for example -- hit the outer ear, they're siphoned straight through the ear canal to hit the ear drum, creating vibrations that the brain will translate into sound.
When we talk, our ear drums and inner ears vibrate from the sound waves we're putting out into the air. But they also have a another source of vibration -- the movements caused by the production of the sound. Our vocal cords and airways are trembling, too, and those vibrations make their way over to auditory processing as well. Your body is better at carrying low, rich tones than the air is. So when those two sources of sound get combined into one perception of your own voice, it sounds lower and richer. That's why hearing the way your voice sounds without all the body vibes can be off-putting -- it's unfamiliar -- or even unpleasant, because of the relative tinniness.
The sound of your own voice isn't the only place where daily perception can butt up against the ugly truth: We often feel uncomfortable when we see our bodies as other people see them, too.
Think about it: Chances are good that most of the times that you look at yourself, it's thanks to a mirror or some other reflective surface. But those are mirror images -- our bodies are flipped. Because most faces are pretty asymmetrical (under close observation, anyway), a flip can create really jarring changes. That's why you might wince at photos that show the real you instead of a mirror image.
“We see ourselves in the mirror all the time—you brush your teeth, you shave, you put on makeup,” Pamela Rutledge, director of the Media Psychology Center, told The Atlantic. “Looking at yourself in the mirror becomes a firm impression. You have that familiarity. Familiarity breeds liking. You’ve established a preference for that look of your face.”
So it should come as no surprise that being reminded that our faces -- and voices -- are slightly different than we think them to be can be a bit unnerving.