Speaker 1: I'm Kristin Conger and I'm Caroline Irvan, and we're hosts
Speaker 1: of the podcast Stuff Mom Never told you That gets
Speaker 1: down to the business of being women from every imaginable angle.
Speaker 1: That's right. Kristen and I skillfully decode the biology, psychology,
Speaker 1: and sociology of ladies and gents from their evolutionary past
Speaker 1: a millennial present to better understand all of that stuff
Speaker 1: Mom never told you. No offense moms, now be sure
Speaker 1: to subscribe wherever you get your podcasts. Hey, brain Stuff listeners.
Speaker 1: There are constantly things that pick my curiosity that I
Speaker 1: want to learn more about, and I'm sure it's the
Speaker 1: same way for you. That's why I enjoy The Great
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Speaker 1: They take a look at the research behind intelligence, using
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Speaker 1: and learning how to make ourselves smarter, which you know
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Speaker 1: slash brain Stuff. Welcome to brain Stuff from How Stuff
Speaker 1: Works crossover into brain Stuff Now. Children all are welcome.
Speaker 1: I'm Christian Seger. But before we go into the light together,
Speaker 1: there seems to be some confusion among you about what
Speaker 1: white noises. No, it isn't. When you have that snowy
Speaker 1: static on your TV and ghosts fly out of the
Speaker 1: screen and your daughter says, they're here. No. White noise
Speaker 1: is something we've all heard, some of us without even
Speaker 1: knowing it. So let's define what it is exactly, how
Speaker 1: it's used to mask other sounds, and what other colors
Speaker 1: exist on the spectrum of sound. The simplest definition is
Speaker 1: that white noise is the noise produced by combining all
Speaker 1: the different frequencies of sound together at once. Each of
Speaker 1: these frequencies are projected at an equal amount, from low
Speaker 1: to high. Because white noise has an equal energy distribution,
Speaker 1: sound technicians refer to its frequency spectrum as being completely flat.
Speaker 1: Some machines like fans, for instance, can create an approximation
Speaker 1: of white noise by hitting all of these notes. That's
Speaker 1: why they're so good at creating background noises that masks
Speaker 1: other sounds. When there are sudden changes in noise, were
Speaker 1: often distracted by the jarring clash, especially if we're sleeping.
Speaker 1: White noises masking effect blocks out those changes, making it
Speaker 1: easier to sleep through the night. That's one reason some
Speaker 1: people leave a fan and air purifier, or even a
Speaker 1: television on in the middle of the night. This sound
Speaker 1: masking is also used to block noise in places like offices,
Speaker 1: hotels and libraries often broadcast over a PA system. If
Speaker 1: you're trying to concentrate in a disturbing environment and there
Speaker 1: aren't filters like these in place, you can even listen
Speaker 1: to white noise on your headphones to mediate the conflicting noise.
Speaker 1: How do you we write these brain stuff episodes? When
Speaker 1: we all live together in this tiny little studio prison
Speaker 1: and are never allowed to leave, There is peace and
Speaker 1: serenity in white noise. It can also be used as
Speaker 1: a kind of therapy for people with ringing ear, also
Speaker 1: known as tenitis. I've got that because of its equal
Speaker 1: high and low frequencies. For more info about how ringing
Speaker 1: ear works, check out our previous episode on the topic.
Speaker 1: And one other thing to note is that, because of
Speaker 1: an effect called stochastic resonance, some people actually find that
Speaker 1: white noise makes their tonitis worse. Now we call it
Speaker 1: white noise because it's analogous to how white light works,
Speaker 1: being made up of all the different frequencies of light.
Speaker 1: But white noise isn't the only color on the sound spectrum.
Speaker 1: Depending on the way signals are distributed over different frequencies,
Speaker 1: they can be red, blue, violet, or gray, pink, noise,
Speaker 1: for example, is very similar to white noise, but it's
Speaker 1: higher frequencies have less intensity, making it louder and more
Speaker 1: powerful on the low end. This makes it useful for
Speaker 1: testing speakers and amplifiers. Like white noise, it's also used
Speaker 1: to mask background sounds, and pink noise even occurs naturally
Speaker 1: in heartbeat rhythms, meteorological data, and the radiation output of
Speaker 1: astronomical bodies. Check out the brain stuff channel on YouTube,
Speaker 1: and for more on this and thousands of other topics,
Speaker 1: visit how stuff works dot com.