Why Do We Feel Nostalgia?

Hey, Vsauce. Michael here.

Music. Why does music make us feel the way it does? Why does music make us wanna move? And why do songs sometimes get stuck in our heads? James May, from the YouTube channel Head Squeeze, thanks for the music. Pleasure.

Why can music bring back memories? That is a very good question, actually. I've often wondered why it has this power, actually, to unlock a completely dormant memory, something that's gone as far as you know, and then it chooses, usually a pop tune from say ten or twenty years ago, bang, there you are, wherever you were at the time. Sometimes it's positive, sometimes it's negative, but what is nostalgia?

Well, it turns out that nostalgia and feeling emotions because of music and dancing and getting songs stuck in your head all orbit around a common theme—your identity. Because, really, physically speaking, who are you? Every single day you are losing atoms and gaining new ones from what you eat and drink. It takes about five years to replace every atom in your body, which means that the matter that we call you today was not part of you five years ago.

If we speed the process up we start to see that your physical body, really all of us, every human on earth, is just a temporary group of atoms and molecules that, nonetheless, keep the same name the whole time. Now this is what we think of when we think of our bodies, but to an alien, who could track individual atoms, and only saw maybe a few frames per decade, you would appear to be what you really are: a bunch of incoming atoms, making your shape and then leaving.

So, what's consistent here? What are you? Nostalgia, fondly remembering the past, what you used to do and who you used to be might simply be a way for your brain to answer that question or at least cool down the anxieties it causes. Because even at a macroscopic scale, you are always changing. You have different friends, different behaviors, different moods, different tastes all the time.

If you grew up in the 80s, and by that I mean the 1680s, it would have been possible to have been nostalgic for a time before the word nostalgia existed. That's because in 1688, Johannes Hofer coined the term by combining the Greek words for returning home and pain. Nostalgia was originally seen as a quite serious medical condition, affecting soldiers who missed home so much that they broke down and were unable to fulfill their duties.

The only cure, as Hofer saw it, was to be sent home, to your home, because nostalgia is really all about you: your memories, your past, who you used to be and consequently who you are now, which makes nostalgia an often healthy way to answer the question, "Who am I?"

Well, you're a person who remembers specific events in the past. You existed in the past and are a continuous being. A popular theory argues that the psychological effects of nostalgia, connecting with your younger self and building a continuous identity, are advantageous, and so we're naturally selected to be rewarding experiences. You change your habits, your friends, your job, you learn things and forget things, but nostalgia allows you to connect all of those events, which is especially helpful during times of major life transitions, like entering adulthood or aging, when studies showed that nostalgia is at its strongest.

But if tucking in and lining up all of your life experiences into a continuous story is so advantageous, why don't we feel nostalgic for everything in the past? Why don't you feel nostalgia for what happened one minute ago? Why don't you feel nostalgic for the way this video began?

Well, the lifespan retrieval curve might offer some clues. It's an average plot of distinct autobiographical memories and it reveals what is called the reminiscence bump—a time between 15 and 30 years of age, where more memories are encoded. This time in your life, both while you are living it and later, is thought to be important because it's so linked to the formation of our self-identities. Memories formed during that bump tend to be the ones we are most nostalgic for, and because we want our continuous identities to be positive, we tend to be nostalgic for good memories, not bad ones.

Individually and collectively, we also tend to be nostalgic and reminisce on things as if they were better than at the time they really were. Twenty years after leaving his hometown, Abraham Lincoln returned to it, and looking upon it, remembering it nostalgically, he wrote these lines of poetry:

"My childhood's home I see again,
And saddened with the view;
And still as memory crowds my brain,
There's pleasure in it too."

Abraham Lincoln might seem like a quite ancient person, someone from way back in history. But here's some perspective. On February 9, 1956, a date within the lives of some of our parents and many of our grandparents, this old man appeared on the television show "I've Got a Secret." What made him so special?

Well, he was Samuel J. Seymour, an eyewitness.

"Goodnight, Mr. Seymour. How old are you, by the way, Sir?"

"Ninety-six."

Ninety-six years old. He was alive and in attendance at Ford's Theatre on the very day Abraham Lincoln was assassinated. And he was alive recently enough to have appeared on national television.

Music doesn't have to bring up old memories or make you feel nostalgia in order to help you build an identity. Lawrence Parsons, in a great interview, discusses the fact that babies from about six months to one year clearly respond to all kinds of different rhythms and chords when only a single note or beat is out of place. But after one year, babies tend to only respond to rhythms and chords from their own culture, from the world around them.

This makes sense when you consider just how important it is for our brains to not only construct a continuous individual identity but a continuous identity within the groups that we belong. We don't always get along with or understand other people, but when two people listen to and respond to music, their feelings and emotions can become more similar than if they were to merely sit in silence or use words with no rhythm.

So, although we are still not exactly sure why music makes us wanna move, the desire you have, the impulse you have to tap your foot or bob your head or, if confident enough, dance when you hear a rhythm might have less to do with the behavior you have learned and more to do with your internal desire to fit in.

And as a consequence of our impressive ability to communicate and be social, it even happens when you are alone or when you want to dance as if no one is watching. Speaking of dance, William Michael Brown motion captured good and bad dancers so he could render them into digital stick figures and remove all clues as to their fitness or looks or health.

Now, figures with symmetric movement, what we might call good dancing, were consistently rated as more attractive and more desirable as mates. But this may have less to do with music being some special human behavior and more to do with communication in general. Sharing a musical experience with someone else might just be an extreme form of the communication skills that were naturally selected into us, so that we could understand each other, understand an emotion from tone of voice and listen.

Sweet, fatty foods taste good because they signal our brain that they are full of energy—energy that we need to survive. This is why cheesecake tastes so incredible. But it doesn't mean that cheesecake is necessary for survival. Music might be the same way—a happy accident of the communication skills we developed but fundamentally an unnecessary one or, as cognitive scientist Steven Pinker famously called it, acoustic cheesecake.

If not properly chewed, a bite of cheesecake can get lodged in your throat. But a short repetitive song can get lodged in your brain. It's called an earworm. At best, it means that the song is catchy. At worst, it means replaying over and over and over again the same song in your head until you are annoyed. According to research by James Kellaris, nearly all of us experience earworms. Men and women experience them equally as often, but for reasons we don't quite understand yet, earworms tend to last longer for and be more irritating to women.

Repetitive rhythms make a song easier to reproduce in our heads, and unusual time signatures or unresolved or incomplete musical ideas bother us. Perhaps because we strive to communicate completely and clearly, we fixate on these little snippets of songs, replaying them over and over again in our heads, hoping to resolve them, which, of course, they don't, meaning that they are quite literally a cognitive itch—an itch that just gets worse by being scratched.

Our inability to suppress a simple thought, like the famous "quick, whatever you do, don't think of a pink elephant" or the game or a song stuck in your head might be explained by ironic process theory—the idea that in our brains there are two different processes going on. One, which consciously controls what we think about, and the other unconsciously monitoring what we are thinking about.

They share an equal amount of cognitive effort and they're always in balance, and so more effort put into monitoring what you're thinking about means that there's less left to actually control what you think about. Spending that cognitive effort on some other task that uses working memory, like Sudoku or anagrams, can often help get an earworm out of your head. You can always just replace the earworm with another one, using a service like Unhear It.

Earworms are annoying, but music has the power to conjure up all kinds of other emotions when we hear it. A major reason for this is the fact that, like our sense of smell, music is initially processed in the same regions of the brain that process memories and emotion, like the amygdala.

So, maybe those are answers—memories. You might not have the same friends and job and house and atoms throughout your life, but you do have the same memories. So, are you just your memories? Well, unfortunately, that idea is a little troublesome, because memory loss doesn't necessarily make you a brand new different person, and there's also the slight problem of false memories.

These studies always freak me out. Researchers bring in participants and show them photographs from their childhood and ask them to tell a story about what happened in the photo, except one of the photos has been photoshopped. It didn't really happen. But instead of noticing this fake image, people tend to just make up a story and remember it as if it really happened.

A couple of weeks ago, I went with Jake Chudnow, who does the music here on Vsauce, to the Royal Observatory in Greenwich. We saw the seventh-largest telescope on Earth, and while there, this song was playing. It's called "Longplayer." Composed by Jem Finer, Longplayer is constructed by combining different recordings of singing bells. They're combined in different ways so as to never repeat for 1,000 years. Longplayer began in 1999 and it will not finish—the song will not be over for 1,000 years.

Literally, billions of humans will be born and die before Longplayer is finished playing. The sound waves, the compression waves that send Longplayer into your ear aren't that much unlike you—your waves of atoms, temporarily organizing atoms or molecules but not really causing any one atom or molecule to stay along with you for the entire journey. Just as the ocean waves and bells ring, as Alan Watts said, the earth peoples.

In a way, you are a slow compression wave moving through Earth's matter. But what does your wave sound like? Does it make people wanna dance? It probably won't echo around for centuries after you're gone, but maybe, while you are here, you can get stuck in the head of some other temporary wave—an earworm that they like and don't want to get rid of. That'd be a nice type of wave to be.

But can music make you smarter, and can I play an instrument? Well, to find out, follow James and I over to the YouTube channel Headsqueeze, where we take a look at those questions.

And as always, thanks for watching. Thank you. Seriously, follow us over. No, seriously. Right now. There's also a link I'll put in the description, so it's like a piece of cake, guys. Come on. Well, we'll be over there waiting. He's over there, I'm over there, I'm with him here, and he's with me over there. We won.