Stuff You Should Know - How Déjà Vu Works

Episode Date: March 24, 2009

Does this episode seem strangely familiar? If so, you might be experiencing déjà vu, a topic that scientists are beginning to study seriously. Discover the myriad theories about how déjà vu works in this podcast from HowStuffWorks.com. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

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and get up close with both legendary figures and emerging talents in the industry. Part of the enormous significance of reggaeton is really the way in which personal narratives connect to larger things going on historically and socially. Listen to El Flow on the iHeartRadio app, Apple Podcasts, or wherever you listen to your podcasts. Brought to you by the reinvented 2012 Camry. It's ready. Are you? Welcome to Stuff You Should Know from HowStuffWorks.com.

And be sure to check out the new Stuff You Should Know blog now on the HowStuffWorks homepage. This podcast is brought to you by Audible.com, the Internet's leading provider of spoken word entertainment get a free audiobook download of your choice when you sign up today log on to audiblepodcast.com slash stuff today for details hey and welcome to the podcast i'm josh clark with me is charles w chuck bryant uh and you put the two of together, you know that you have stuff you should know. Right, Chuck? That's right, Josh. What you doing there, Chuck?

I know you're laughing because I am doing a little thing. I have gunk in my ear. Yeah? And I could use a Q-tip if you have one. Hey, fun fact. Did you know that Q-tips were originally called baby gays? Baby gays? I don't think I knew that, but it sounds familiar. Yeah, true story. True story. Very cool.

I like starting off with a fact. Yeah. That has nothing to do with our show. Sure, right. So, Chuck, speaking of having nothing to do with our show, let's talk about Deja Vu. You ever had it? I have, and let me add, this is a listener suggestion. Yeah.

Dedicated to one Peter Harrison of Pittman, New Jersey, keeping it real in New Jersey in the Garden State. Yeah. He actually had deja vu when he was listening to, I believe, our Exorcism podcast. Weird. There you have it. That's an unsettling one to have deja vu over, I would think. Yeah. It turns out we had a great article on it, so away we go.

Yeah, let's do this, Chuck. You know, are you part of the 30 percent who uh has reported never having or i guess just hasn't reported having deja vu are you part of the 60 to 70 percent 60 to 70 i definitely have had deja vu many many times i was actually surprised to find that number was as low as it was i thought it'd be hovering in the 90s you know and then the other people were just too lazy to ever say yeah i, I've had deja vu. Right. It seems like something everybody would have, right? Right, or nothing familiar has ever happened to me.

Exactly. Like, I don't pay attention to anything at all. Right. I just watch, you know, Dancing with the Stars all the time. Right. So, all right, Chuck, well, let's start with the nuts and bolts, shall we? Deja vu, French 4. French 4, already seen, and I believe it was named by Emile Borac, who was a French scientist.

First guy to ever study it. So he gave it its name. Yeah. In his 1876 book, L'Avenir des Sciences Physiques. Wow. Thank you. Three years under my belt, pal. I feel like you just channeled Pepe Le Pew.

Yeah. So Deja Vu, as everyone knows, is a feeling that you've seen or experienced something before when you know that you have not. Yeah. Yeah, it's a sense of familiarity, unplaced familiarity. Right. For instance, I walk into a store I've never been in and see a person I've never seen. I think, wow, this feels eerily familiar. Yeah.

What usually happens to me i'm part of the 60 to 70 percent to of course self-reported sure um and uh what happens to me usually is there's about three different things that are going on in conjunction with one another like um you know a fish jumps in a lake and a woman walks by with a baby stroller and then like a cloud passes in front of the sun. That's how my deja vu is. And I'm like, wow, I've been standing in the same spot watching the same group of things happen and then it just kind of passes.

Interesting. I'm like, whoa. I don't know if I could categorize mine that specifically, but well done. Thanks. Thank you very much. That's my deja vu. Cool. But, yeah, so essentially what was the guy's name boirac yes he uh he he mentioned deja vu but he didn't

really go into detail about it the first really respected i guess scientist to really take up the mantle was freud right yeah and he basically created the theory that was the driving explanation behind deja vu throughout the 20th century. And that was that he believed that deja vu was the result of repressed memories. He said that about everything. Everything. If it wasn't about the penis or the vagina, it was about repressed memories and possibly a mother's teat. Right. Yeah. I went to the Freud house. Did you? Yeah, I have a nice photo in front of it. That's great. Just a sidebar.

What city is that? Vienna? I am almost positive it was Vienna. We'll find out, won't we? Yes. I traipsed around though and all those memories aren't firmly rooted. There's a deja vu joke in there somewhere i just can't find it right now so we'll just keep going huh sure we'll edit it in later all right so at some point as we said freud you know he deja vu explained and then once freud basically was found out to be a um basically a fraud no just kidding well um, a coke-addicted postulator rather than maybe a real scientist. In my opinion, I'm more of a Jungian than a Freudian. Yeah, of course.

I'm a Dr. Phil guy. Are you? No. You can't go wrong with that guy. Eventually, at some point in time, deja vu was attached to the paranormal. Right. I'm not entirely certain when this happened, but you you know, you've heard that kind of thing. Like, it had to do with precognition.

Yeah, and real scientists wouldn't. They kind of just brushed it aside. Well, actually, one does explain Deja Vu through precognitive dreams, but we'll get to that later, right? That's right. But, yeah, any time you put the stank of paranormal onto something that's arguably real, science just turns their back on it. They can't stand things that they can't apply the scientific method to, whether it's real or not, right? So everybody just kind of dropped, at least the scientific community kind of dropped Deja Vu

until our great friend, the functional MRI was invented. Yes, the MRI. A.K.A. the wonder machine. Right. And it sparked this renewed interest in research into into deja vu right well yeah because now you could actually look at the brain function and try and figure out the science behind it instead of just doing the freudian thing right which is make stuff up right um so uh this is really really really new research i mean just last several years, right?

So the jury is still definitely out, which is good for us and our listeners because we get to talk about a bunch of competing theories that are super cool. And there's a lot of them. I think the article sits on like over 40 theories of what deja vu actually is. And I think we shouldn't go into all 40. There's no way. This would be a four-hour podcast. But they basically split deja vu into two broad categories, right? Yes.

There's associative and biological. Right. And which one's associative? Well, that's the one that most people out there are probably more familiar with, and that's when your senses are reacting, and you see, hear, or smell something that stirs up a feeling inside you. And it's memory-based. And it's very fleeting, like 10 to 20 seconds. Yeah.

Mine are shorter than that, actually. Yeah? I would say less than 10, usually. Huh. Is there a baby carriage involved? No, never. This is a deja vu among generally healthy people, right? Yes.

So we're not really attaching any real meaning to it. It's more like a, whoa, that was cool deja vu kind of thing. Right, right. The other one, biological, is actually the result of some sort of structural impairment to the brain. Yeah. Say epilepsy. Exactly. That's a big one.

Yeah. Possibly schizophrenia. Mm-hmm. say epilepsy. Exactly. That's a big one. Yeah. Possibly schizophrenia. And these episodes are much more vivid deja vu than associative deja vu. Right. And people who experience biological deja vu have much more of a tendency to attach real meaning to it and really believe like they're experiencing something twice. Right. It's not like a fleeting feeling. No. Yeah.

And if you're an epileptic and you have a case of vivid deja vu, prepare for a seizure. Oh, it's right before the seizure? Right before, yeah. And apparently they also smell flowers sometimes too or oranges. That's what I've heard. Interesting. I agree. So those are the two broad categories, right?

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No, it doesn't. With the biology, it seems like researchers have the biological explanation of deja vu down a little more pat. Right, it's a little more medically based. Yeah, it's like a temporal lobe malfunction, possibly. And actually, it seems like the temporal lobe has everything to do with deja vu, whether it's structural or associative. Right, because that's where our conscious memory is happening, basically. Which would be a pretty appropriate place for deja vu to take place, right?

Absolutely. So basically, there's this part called the, there's a temporal lobe region called the medial temporal lobe. And that's, like you said, the part that's responsible for processing conscious memory. And there's this guy named Robert Efron. Yes. And he's a neurologist, I take it, of some stripe. And he did some investigation into the temporal lobe. And he found that it receives

information the same sensory input twice right okay in the early 1960s too yeah and it still held up as valid it makes a lot of sense yeah okay so what what efferent postulated was that if we're getting the same information twice one's direct to the temporal lobe, which processes sensory information. The other one is slightly indirect. It gets routed through the right hemisphere of the brain and then shoots over to the left hemisphere of the temporal lobe. Within milliseconds. But there is a delay. There's a lag. And so what Efren said was if this delay is longer than normal, extended by even a couple of milliseconds,

the brain has the potential to confuse what, I guess, kind of timestamp or what situation or context that this sensory input was taken in. Right. And maybe assign it an incorrect category. Hence, we get the feeling that we've been there before, we've experienced this before because we're confused and that's what deja vu is, which makes tons of sense, right? Pretty cool, yeah. That's certainly not the only theory of what deja vu is. No.

Cell phone theory, shall we talk about that? Yes. This Dr. Alan Brown is a guy who's done a lot of research in this area as well, Dr. Alan Brown is a guy who's done a lot of research in this area as well. And he did studies at Duke University and SMU Southern Methodist with Elizabeth Marsh is the lady's name. And what they did was they worked with subliminal suggestion, which is one of my favorite things. I think it's really cool and interesting. Agreed. They showed photographs of different locations to students.

And they were going to, you know, the plan was to ask them which ones were familiar. But before they did this, they showed the same photos at subliminal speeds, so like 10 to 20 milliseconds. Gotcha. And what happened was the brain, of course, registered it. But unconsciously, right? Unconsciously. Right.

And they found familiarity with these slides of locations that they'd never been to. Like they showed the people the same picture once in a split second. Right. And then later on, they thought that they hadn't seen it before, but the brain had already unconsciously processed it, right? You got it, buddy. And there was an increase in deja vu among those people? Yeah.

And I saw a thing on YouTube, and this isn't exactly deja vu, but this is a really cool thing. There was a guy in England named Darren Brown. He's a magician and mentalist, which I think is a great title. And he did this. If you look up on YouTube, Darren Brown and subliminal advertising, he did this cool deal where he brought in these two advertising guys and said, hey, I want you to come up with an advertising plan for me based on taxidermy. And that's all he told them.

And then he set down an envelope and said, this is my plan, and don't look at it or anything like that. It's sealed. These guys came up with a little sketch and a logo and a tagline. He came back in 10 minutes later, or however long it was, and opened up his envelope. And the logo, the tagline, everything was really, really, really similar. And these guys, these ad guys, were just blown away. And then it showed a replay of their trip to the studio where they did this, and he had placed these little subliminal suggestions everywhere.

One was a little sticker on the inside of their cab. One was on a road sign that they passed. One was a group of students that were wearing a t-shirt with the logo that passed in front of the car. And their brains picked all this stuff up. It was a really, really cool thing. What was the guy's name again? Darren Brown. Okay. What was the name of the clip? Do you remember? Darren Brown, Subliminal Advertising. Nice. Good enough. Very direct and appropriate. Yes. So what are you doing there, Chuck? You okay? Well, yeah, my ear has got some gunk in it. Oh, yeah? Yeah, I could use a Q-tip, actually. Hey, Chuck, did you know that Q-tips were originally called baby gays?

Gay as in G-A-Y-S? I didn't know that, but that sounds familiar. Yeah, back in the 20s. Interesting. Weird. Another aside, sorry. sorry uh so okay chuck that um cell phone theory right that's what it was called uh-huh that was alan brown yeah so it um it it applies to deja vu in that i guess dr brown saying that we are when we're not really paying attention when we're distracted right um we're still processing sensory information unconsciously so then let's say you walk into a room and you're not really paying attention you're talking to somebody um when you do turn your attention to your surroundings and you start taking that sensory input in consciously that's where potentially where deja vu comes in right because we're

comparing this new conscious sensory input to something our brain's already familiar with and we're like whoa i've been here before. Right. I know they found that some people that are stressed and have anxiety are more prone to it. They also found that people who are refreshed and rested are more prone to it. So, yeah, we're still getting a handle on deja vu, right? Yeah. One study says one thing.

The other says the exact opposite. I love those. I've got another study. Beautiful. Let's hear it. It's called the hologram study. Ah, good one. This guy's name is Herman

Snow. S-N-O. No W. He's Dutch. He basically has a theory that memories are like a hologram, right? Like a 3D construct. If you take just a small piece of it, you can reconstruct the memory from it.

Right. But if you take a very, very small fragment, the memory is not going to be completely accurate or true. Right. So Dr. Snow's theory, or actually I think he's a philosopher maybe, his theory is that we have little snippets of memory brought back we recall them that are triggered by something familiar but then we reconstruct those memories incorrectly and we use that immediate um experience right uh say getting into a car uh we have a memory that we've forgotten about a similar car um so but we still recall a little bit of it, but we reconstruct it around the car that we're in right now, and we feel like we've been there before.

Right. He's a psychiatrist, by the way. Thank you for that. Thank you. No listener mail on that one. Fact-checking as we go. Yeah, you're quick, Chuck. Thank you.

You got any more? Well, I know you probably wanted to hit the precognitive dream thing. Yeah, and I don't remember who came up with this one, do you? Yeah, a Swiss scientist, Arthur Funkhauser. Okay, so Funkhauser, with the coolest name on the planet, he believed that we actually have dreams that pretend the future, essentially. Very cool. And that it's generally mundane stuff that we easily forget.

And he actually conducted a study, I think back in 1939, of a bunch of kids at Oxford and found that somewhere around like 12.7% of their dreams eventually bore a striking similarity to future events. Right. And he said it's as simple as that we we have somehow have an ability to see what's coming down the road right uh and that's where deja vu comes from well i did like you said it was usually more mundane things what he theorized and this makes sense too is that if if it wasn't mundane we're more likely to remember it in our you know just waking conscious right and these are the ones that slip between the cracks.

Right. And since it was mundane, since we can forget it, that would explain that kind of hazy quality that deja vu always has. Right. Nothing's quite right all of a sudden. It's pretty cool. Yeah. And actually, interestingly, his theory was backed up by another study from 1988. It found similar results, except it was more in the 10% of dreams pretend the future.

I think it's actually 10% of the people have dreams that could, not 10% of dreams. Are you sure? Yeah. I would say 10% to 12% of my dreams come true. Really? It's happening right now. You dreamed of having a podcast with me one day? Nice one, Chuck. Yes. Should we talk about jamais vu? Yes, please. Jamais vu is the opposite of

déjà vu. I know a lot of people say vous j'ai des, but that's just kind of a funny way to say it. Jamais vu is actually a real term. I passed over this part in the article, Chuck. I'm not kidding. This is brand new to me. It was not in the article, Chuck. I'm not kidding. This is brand new to me. It was not in the article, my friend. It's called Supplemental Research. Oh, good. You should try it sometime. I thought I was having jamais vu.

No, jamais vu is a real thing. It means never seen, and it's when a familiar situation is not recognized. It's like face blindness. Not really. Okay. It was worth a shot, Chuck. Right. Actually, have you ever had the situation where you've said a word over and over in your head,

and then the word starts to sound funny? Mm-hmm. Or that happens to me when I see it spelled. Right, exactly. That's jamais vu. And basically what's happening there is the word is just existing in its form, so the function of meaning is lost. Weird.

You're not applying the function and meaning, so you say eggs benedict 15 times, and by the end of it, or if you write it out 15 times, you're going to be thinking, eggs benedict, what are eggs, and what is benedict, and what is hollandaise sauce? This word looks so weird. Yeah, that's one example of jambigo. Don't forget the Canadian bacon, Chuck. Who can? Yeah, I don't know of jambigo. Don't forget the Canadian bacon, Chuck. Who can? Yeah, I don't know.

Our Canadian friends, we love your bacon. They just call it bacon up there. Yeah, well, we call it ham. That's true. So, wow, Chuck, you dazzled me just now. Good. Yeah. I like to do that from time to time.

Well, that's deja vu, I guess, for now until somebody finally cements down exactly what's going on. And again, I think the Wonder Machine is going to be the utility that does it for us. Deja vu all over again, as Yogi Berra once said. Great man. Yep. And Chuck, I think it's time to say hey to the people at Audible. Audible.com, one of our beloved sponsors. Even better than that, let's tell everybody that the people at Audible. Audible.com, one of our beloved sponsors. Even better than that, let's tell everybody that the people at Audible are trying to say hey to all of our listeners.

If they go right now to audiblepodcast.com slash stuff and sign up, they'll get one free download. Yep. And this is actually kind of big. They have 50,000 plus titles on the site. So you can get a book if you want? Yeah. You can get stand-up. And actually, I was looking on the site, and they have a bunch of George Carlin,

and specifically A Place for My Stuff. R.I.P. Arguably his greatest work ever. It's my personal favorite. So yeah, there's all sorts of, it's not just audio books. Yeah, I love Carlin. And speaking of which, this isn't an audio book either. And I'm surprised you didn't pick this one as your plug.

Leave me alone. The Gonzo Tapes, The Life and Work of Dr. Hunter S. Thompson. These were just recently released. And these are just, it's a long series. I believe it's an abridged version on audible.com. But you get about six hours worth of famous author extraordinaire Hunter S. Thompson speaking into a tape recorder over the years. He did this. And they've gathered all these tapes, and it's really, really awesome.

I have found my one free download. Yep. So what I will be doing is going to audiblepodcast.com slash stuff and signing up. So, Chuck, I know you love plugging the blog. You want to take the opportunity? Sure. I would like to direct everyone to our new blog, which is an internet term for blog. And Josh and I write on this thing a couple of times a day and we talk about cool stuff

and basically the idea here was to get the Stuff You Should Know Nation involved with each other in leaving comments and talking to each other and reading about cool stuff that they should know instead of just listening to us say it. And also, don't forget to join the Stuff You Should Know Nation. We are actually buying a plot of land. Right. We'll be sending details out via our blog, ironically enough. And you can access it through the homepage on HowStuffWorks.com.

Oh, yeah. And it's called Stuff You Should Know. Yeah, appropriately enough. And you can see a lovely photo of Josh, who looks cute as a dang button. And Chuck in his flat cap. That's right. Looking good. It's good stuff.

So now... Yeah, there's the blog plug. Let's do Listener Man. Right. You ready for this, Josh? I was born ready, Chuck. I have a couple of stuff we should knows. Oh, okay.

Our new nicer name for corrections. Wait, I thought it was stuff we should have known. Sure. Okay. Sounds good. All right. Christine Lee of Toronto, Ontario. And as a quick side note, I can't remember his name,

but we had a Canadian friend write in and say it really bugs when we say like Montreal, Canada. He said that'd be like saying Atlanta, United States. Sorry. We need to start saying the province. Bacon. So Christine Lee is of Korean descent, and she said in the Friday the 13th podcast, we talked about unlucky numbers in China and Japan. And again, in Can People Die of Fright, we talked about the same thing.

And it's actually true in Korea as well. And she feels like Koreans are often slighted to their Chinese and Japanese friends. Really? So we need to start looking into other Asian countries, basically. Yes. So apparently four is an unlucky number in Korea, and thank you, Christine Lee, for that. Sorry, Christine.

And Chris from Pennsylvania, you're going to love this one, he said he listened to the Comus podcast. I'm surprised that between Josh's Magnum PI knowledge and Chuck's movie knowledge, you guys never brought up the connection between Magnum and the 1978 movie Coma. Tom Selleck was actually in that movie, and I haven't seen it in years, but I remember him being one of the coma patients that was suspended on wires, and that is indeed true.

I don't remember Tom Selleck in that one. My earliest memory of Tom Selleck in a movie was Looker. No, he wasn't in that. Okay, what was the other one with the robots then? Right, you're thinking of Runaway. Very nice. Are you sure he wasn't in Looker? Yeah, that was Albert Finney. That was a great movie

though, for an 80s sci-fi. I agree, Susan Day's in it too. Alright, well we should probably get out of here before Chuck and I say something to embarrass ourselves, right? Further. Yeah. So thanks for listening.

I would advise everybody to go onto the site and check out How Deja Vu Works, a fine article written by our colleague Leanne Obringer. There's a nice little Easter egg hidden in the article that may induce deja vu in you. You can find that by typing in how deja vu works in our handy search bar at HowStuffWorks.com. And if you want to send Chuck and I a message via electronic mail. A non-haiku related message. Yes, Chuck. Yes. Non-haiku.

You can alert us at StuffPodcast at HowStuffWorks.com. For more on this and thousands of other topics, visit HowStuffWorks.com. Brought to you by the reinvented 2012 Camry. It's ready. Are you? Hey, what's up? This is your boy, Jerry Clark, and I am the host of Storytime with Legendary Jerry Podcast. It's ready. Are you? the South. Southern Rap has had the game on lock for years, and now I'm telling you legendary stories of how we did it. Listen to Storytime with Legendary Jerry on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts. I am the ferryman.

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