1 00:00:00,680 --> 00:00:03,880 Speaker 1: I'm Kristin Conger and I'm Caroline Irvan, and we're hosts 2 00:00:03,880 --> 00:00:06,720 Speaker 1: of the podcast Stuff Mom Never told you That gets 3 00:00:06,720 --> 00:00:10,200 Speaker 1: down to the business of being women from every imaginable angle. 4 00:00:10,520 --> 00:00:14,400 Speaker 1: That's right. Kristen and I skillfully decode the biology, psychology, 5 00:00:14,480 --> 00:00:18,000 Speaker 1: and sociology of ladies and gents from their evolutionary past 6 00:00:18,040 --> 00:00:21,880 Speaker 1: a millennial present to better understand all of that stuff 7 00:00:22,000 --> 00:00:25,400 Speaker 1: Mom never told you. No offense moms, now be sure 8 00:00:25,400 --> 00:00:31,120 Speaker 1: to subscribe wherever you get your podcasts. Hey, brain Stuff listeners. 9 00:00:31,200 --> 00:00:33,960 Speaker 1: There are constantly things that pick my curiosity that I 10 00:00:34,000 --> 00:00:36,320 Speaker 1: want to learn more about, and I'm sure it's the 11 00:00:36,360 --> 00:00:39,200 Speaker 1: same way for you. That's why I enjoy The Great 12 00:00:39,240 --> 00:00:42,639 Speaker 1: Courses Plus and I keep encouraging you to sign up 13 00:00:42,640 --> 00:00:46,040 Speaker 1: for it. 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Now here's a course I recommend that 23 00:01:19,319 --> 00:01:23,880 Speaker 1: you watch. It's called The Intelligent Brain. It is really interesting. 24 00:01:23,880 --> 00:01:27,400 Speaker 1: They take a look at the research behind intelligence, using 25 00:01:27,480 --> 00:01:31,959 Speaker 1: brain imaging technology to explore the workings of human intelligence 26 00:01:32,160 --> 00:01:35,360 Speaker 1: and learning how to make ourselves smarter, which you know 27 00:01:35,560 --> 00:01:37,880 Speaker 1: I would assume that's why you're listening to this podcast. 28 00:01:38,319 --> 00:01:41,520 Speaker 1: Now we've got a special offer for you. We want 29 00:01:41,560 --> 00:01:43,880 Speaker 1: you to sign up for the Great Courses Plus today 30 00:01:43,920 --> 00:01:47,240 Speaker 1: because they are giving brain Stuff listeners a special offer. 31 00:01:47,480 --> 00:01:50,800 Speaker 1: Get an entire month of unlimited access to all of 32 00:01:50,880 --> 00:01:54,640 Speaker 1: their lectures for free. Start your free month today. Go 33 00:01:54,760 --> 00:01:58,240 Speaker 1: to the Great Courses Plus dot com slash brain Stuff. 34 00:01:58,280 --> 00:02:02,120 Speaker 1: Now remember that is the rate Courses Plus dot com 35 00:02:02,160 --> 00:02:07,200 Speaker 1: slash brain Stuff. Welcome to brain Stuff from How Stuff 36 00:02:07,200 --> 00:02:17,000 Speaker 1: Works crossover into brain Stuff Now. Children all are welcome. 37 00:02:17,600 --> 00:02:20,920 Speaker 1: I'm Christian Seger. But before we go into the light together, 38 00:02:21,000 --> 00:02:24,760 Speaker 1: there seems to be some confusion among you about what 39 00:02:25,200 --> 00:02:28,800 Speaker 1: white noises. No, it isn't. When you have that snowy 40 00:02:28,840 --> 00:02:31,120 Speaker 1: static on your TV and ghosts fly out of the 41 00:02:31,160 --> 00:02:34,880 Speaker 1: screen and your daughter says, they're here. No. White noise 42 00:02:34,960 --> 00:02:37,800 Speaker 1: is something we've all heard, some of us without even 43 00:02:37,800 --> 00:02:40,679 Speaker 1: knowing it. So let's define what it is exactly, how 44 00:02:40,720 --> 00:02:43,919 Speaker 1: it's used to mask other sounds, and what other colors 45 00:02:44,040 --> 00:02:48,320 Speaker 1: exist on the spectrum of sound. The simplest definition is 46 00:02:48,320 --> 00:02:51,320 Speaker 1: that white noise is the noise produced by combining all 47 00:02:51,360 --> 00:02:55,520 Speaker 1: the different frequencies of sound together at once. Each of 48 00:02:55,520 --> 00:02:58,760 Speaker 1: these frequencies are projected at an equal amount, from low 49 00:02:59,040 --> 00:03:02,840 Speaker 1: to high. Because white noise has an equal energy distribution, 50 00:03:03,240 --> 00:03:08,480 Speaker 1: sound technicians refer to its frequency spectrum as being completely flat. 51 00:03:09,080 --> 00:03:12,840 Speaker 1: Some machines like fans, for instance, can create an approximation 52 00:03:12,919 --> 00:03:15,959 Speaker 1: of white noise by hitting all of these notes. That's 53 00:03:15,960 --> 00:03:19,200 Speaker 1: why they're so good at creating background noises that masks 54 00:03:19,320 --> 00:03:22,720 Speaker 1: other sounds. When there are sudden changes in noise, were 55 00:03:22,760 --> 00:03:27,080 Speaker 1: often distracted by the jarring clash, especially if we're sleeping. 56 00:03:27,680 --> 00:03:31,360 Speaker 1: White noises masking effect blocks out those changes, making it 57 00:03:31,400 --> 00:03:34,560 Speaker 1: easier to sleep through the night. That's one reason some 58 00:03:34,600 --> 00:03:37,480 Speaker 1: people leave a fan and air purifier, or even a 59 00:03:37,520 --> 00:03:40,440 Speaker 1: television on in the middle of the night. This sound 60 00:03:40,560 --> 00:03:44,240 Speaker 1: masking is also used to block noise in places like offices, 61 00:03:44,520 --> 00:03:49,280 Speaker 1: hotels and libraries often broadcast over a PA system. If 62 00:03:49,280 --> 00:03:52,320 Speaker 1: you're trying to concentrate in a disturbing environment and there 63 00:03:52,360 --> 00:03:55,320 Speaker 1: aren't filters like these in place, you can even listen 64 00:03:55,320 --> 00:03:59,200 Speaker 1: to white noise on your headphones to mediate the conflicting noise. 65 00:03:59,520 --> 00:04:01,960 Speaker 1: How do you we write these brain stuff episodes? When 66 00:04:02,000 --> 00:04:04,800 Speaker 1: we all live together in this tiny little studio prison 67 00:04:05,000 --> 00:04:08,080 Speaker 1: and are never allowed to leave, There is peace and 68 00:04:08,160 --> 00:04:11,840 Speaker 1: serenity in white noise. It can also be used as 69 00:04:11,840 --> 00:04:14,320 Speaker 1: a kind of therapy for people with ringing ear, also 70 00:04:14,440 --> 00:04:17,400 Speaker 1: known as tenitis. I've got that because of its equal 71 00:04:17,480 --> 00:04:20,920 Speaker 1: high and low frequencies. For more info about how ringing 72 00:04:20,920 --> 00:04:24,159 Speaker 1: ear works, check out our previous episode on the topic. 73 00:04:24,480 --> 00:04:26,760 Speaker 1: And one other thing to note is that, because of 74 00:04:26,800 --> 00:04:30,919 Speaker 1: an effect called stochastic resonance, some people actually find that 75 00:04:31,040 --> 00:04:35,240 Speaker 1: white noise makes their tonitis worse. Now we call it 76 00:04:35,640 --> 00:04:39,120 Speaker 1: white noise because it's analogous to how white light works, 77 00:04:39,160 --> 00:04:41,960 Speaker 1: being made up of all the different frequencies of light. 78 00:04:42,400 --> 00:04:46,279 Speaker 1: But white noise isn't the only color on the sound spectrum. 79 00:04:46,320 --> 00:04:50,119 Speaker 1: Depending on the way signals are distributed over different frequencies, 80 00:04:50,320 --> 00:04:55,040 Speaker 1: they can be red, blue, violet, or gray, pink, noise, 81 00:04:55,080 --> 00:04:58,120 Speaker 1: for example, is very similar to white noise, but it's 82 00:04:58,200 --> 00:05:02,640 Speaker 1: higher frequencies have less intensity, making it louder and more 83 00:05:02,680 --> 00:05:05,320 Speaker 1: powerful on the low end. This makes it useful for 84 00:05:05,360 --> 00:05:09,960 Speaker 1: testing speakers and amplifiers. Like white noise, it's also used 85 00:05:10,000 --> 00:05:14,719 Speaker 1: to mask background sounds, and pink noise even occurs naturally 86 00:05:14,880 --> 00:05:20,120 Speaker 1: in heartbeat rhythms, meteorological data, and the radiation output of 87 00:05:20,200 --> 00:05:29,080 Speaker 1: astronomical bodies. Check out the brain stuff channel on YouTube, 88 00:05:29,160 --> 00:05:31,320 Speaker 1: and for more on this and thousands of other topics, 89 00:05:31,480 --> 00:05:46,679 Speaker 1: visit how stuff works dot com.