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