your brain, i guess

0:00 Hi. You're on a rock floating in space surrounded by apes. Good news. You're an ape, too. Good news. Everyone's smart. Good news. Nothing matters and stuff. And I feel sad. How did this happen? Whoops. Might have crossed a line there. You are a brain. Yes, you. Trapped in a prison called the cranium, which is a very prisony name due to it being a prison. But you actually aren't a you. You're a y'all. That is there's thousands, millions, billions of cute little guys talking to each other, which as a whole comes y'all. There's also other guys. They don't do much besides keep you alive and stuff. Anyway, back to our adorable little angels. These guys come in many different shapes and sizes, but not really. They're just kind of unorganized. Each one has a body which contains a nucleus. If you passed eighth grade biology, you may recognize that word. Makes proteins from DNA. The body has a tail, which by the way can be really freaking long. It also has these little branches on each end. The

0:45 branches connect to branches of other neurons which talk through chemicals. The more they talk, the more they stick. The less they talk, the less they stick. It's kind of like plastic. Hey, how do they know when to release the chemicals? Hold on. How does this lump of meat store electricity, a special juice containing salt, which the neurons are submerged in? You remember that tail? Well, inside that tail is a ton of potassium. 10-second chemistry lesson. Ions are special atoms that have either less or more electrons than they need, and they have the inside of the tail has charged potassium, while the outside has the more charged sodium. Both want to move, but they can't go through walls. Fortunately, there's a door, few doors, one's constantly revolving. This door throws three sodium out and pulls two potassium in, meaning at rest, the inside of the tail will have less charge, which actually turns out to be pretty chill. There's some sensors near where the neurons connect, which opens some old school chemically activated doors that let in some positive charge.

1:32 If the signals are strong enough, then a lot of these doors open, and the charge reaches all the way to here. If we zoom in, we'll see new doors. Hey, where did the chemicals come in on these ones? That's the neat part. They don't. With this new technology, doors can be activated by Wo, it was like a chain reaction of electricity. That's a lot of action causing a lot of potential. Hey man, this is pretty slow. Anyway, we could make this faster. Yeah, no problem. Take this. Now the neuron has a nice little coat. But wait, if there's a code, how do the ions get through the door? Good point. Let's cut the code up. Leaving little spaces for the doors where there's a bunch of ions chilling in between each door. Door opens. More charge. Ions bump. More charge. Door opens. And altogether. Wo, that was fast. Hey, that kind of looks like a No, don't. They're different. For the most part, the body of these guys is on this gray outer layer, while the tails stretch to other bodies in this inner white part, tucking through trillions of connections and

2:17 creating knowledge. That's why your brain is so wrinkly and gross looking compared to other brains. Jam as much of this gray stuff in as small space as possible, while smooth brain has much less gray stuff, which means less neurons, which means less knowledge. Wait a minute. Your brain, my brain, and his brain all kind of have the same wrinkles. I wonder if different wrinkles do different things. Story time. One day, there was a guy who couldn't talk, but could understand perfectly fine. It was pretty weird and kind of inconvenient. So they took him to a specialist. Then he died. So you still need that or? Turns out this part of his brain was like not there, which made the specialist think it was responsible for talking. And he was right. Which means this little wrinkle is named after him. And now by destroying people's brains, observing already destroyed brains, we kind of know a little bit about what the wrinkles do. Let's divide them into wrinkle clusters. Wo, what's that one doing? I think it's thinking. probably

3:03 only about like four things max, which is a pretty short memory in that term. It might also be moving your body, but only very intentionally. If you reorient your attention over here, you'll recognize the part of your brain responsible for recognizing stuff and reorienting stuff by processing your senses and thinking about space. It does that, too. It doesn't process your eyesight, though, cuz that job is taken by this guy back here, who also recognizes stuff, mostly images stored in memory. The bottom wrinkles get stuck with the boring stuff, like processing sound, memory, and language. Oh, and recognizing stuff. I think I'm recognizing a pattern, but I'm not too sure. Oh, we ran out of brain to wrinkle. Don't worry, if you crack it open, there's goodies on the inside. The phalamus over here is your standard internet router. All your senses go here before they go to the wrinkles for interpretation, except for smell. Turns out animals were smelling things long before they had a phalamus. Want to stay alive? You'll probably need one of these. Does the hard stuff like

3:49 sweating, hunger, thirst, so you don't have to. Ever had a short-term memory that you wanted to make a long-term memory for a test, but then the test came and you didn't have the long-term memory? It's his fault. That was his job. Blame him, not your procrastination. If this image is making you feel anything, it's coming from the amydala. If it's not, consider yourself one of the lucky ones. It's mostly responsible for fear and anxiety. Oh, and so is the amydala right here. There's a gland looking thing. Hey, don't glands usually make juices and stuff? Yeah, so does this one. It makes a nice cocktail of hormones served hot and ready. Want to move? You'll need this. Want to move but better? You'll also need this. Actually, you'll really need this. Let's play a game. What has more neurons? This little guy or your entire brain and nervous system? Actually, it's not even close. Around 80% of all your neurons are in this little thing. That's 16 billion neurons for pondering the mysteries of the

4:34 universe and 70 billion neurons for hopscotch. You also got these sacks of brain juice, which, you guessed it, make juice for the brain to float around in, which is actually pretty important since your brain has the consistency of Jell-O. If it wasn't floating around, it would just kind of, you know. Finally, the brain stem, which connects the brain to the spinal cord. It helps with more unconscious stuff like blinking, breathing, and facial movements and making your heart do whatever hearts do. You might know that the brain is split where one side is logical and the other side is creative. No, no, no, no, no, no, no, no. Please stop saying this. It's wrong. Also, don't bring up the time I said it. It makes me sad. Sorry. The two sides are split, but more just for wiring purposes. They're connected by this thing and are in constant communication. Just don't cut it. Weird things happen when you cut it. Maybe I'll make a video about that that you might want to watch where clicking a

5:20 certain red button will ensure you don't miss. Wink wink. But we've yet to answer the prevailing question. Why do I feel stuff? Not feel like this feel, but like when I'm having a relaxing walk on the beach, watching the sunset, when suddenly I see a happy couple and realize I'll probably be alone forever. Or when I've been lost at sea for 7 days and my buddy looks increasingly like a Snickers bar that will make me feel like myself again. Not sponsored. These both happen by chemicals. Remember the action potential stuff where chemicals would activate the electricity? Yeah, those. But actually, not all chemicals activate electricity. Sometimes they subtract it by opening doors to let ions out. So, how many of these little chemical guys are there? I don't know. We've discovered about a hundred, though. But there are definitely main characters who you've probably heard of. Dopamine. This guy is the main character of main characters. It originates from neurons right here that pass their juicy

6:06 dopamine along these pathways. So, does dopamine add to the electricity causing it to fire or take it away? If you guessed add, you're wrong. If you guess take it away, you're also wrong. Dopamine is such a main character, it's neither. Rather, it tunes the neuron indirectly. And depending on where it binds to, the type of neuron and where in the brain that neuron is, it can help the neuron fire or stop it from firing. Now, that means dopamine is responsible for a lot of things. But in short, it helps your body do stuff to get stuff it doesn't have. Serotonin, most strongly associated with chill vibes, meaning it also most commonly opens doors to let ions out to prevent neurons from firing. Not always, though. Epinephrine, this is adrenaline, but in the brain, so we call it something much fancier instead, cuz no way esteemed scientists will use the same term as the peasants. But it's adrenaline responsible for your typical adrenaline stuff and usually less ions

6:52 in. Endorphins make pain become less pain. Also make just okay become m Yeah. And the last two I'll mention are your base models, the background characters if you will. They're pretty much everywhere. Glutamate so much. Glutamate. Name any process that involves your brain and glutamate involved somehow. Want to retrieve a memory? Glutamate can help. Learning. So is glutamate. Thinking right now about glutamate. It's your basic default brain chemical. It lets ions in and that's pretty much it. GABA. It's glutamate but opposite. Instead of letting ions in, it lets them out. It's here exclusively for vibes, and you could be, too. Oh, yeah. I forgot to mention, consciousness is a super simple process in the brain.