Your Brain Doesn’t Work the Way You Think

Note

The brain is constantly trying to predict the world around it, updating its model through plasticity and live wiring, which allows for flexibility and adaptation. Synesthesia is a condition where senses are mixed, such as seeing colors when hearing music, affecting about 3% of the population. Teaching methods should adapt to the next generation’s ability to access information instantly, encouraging interactive projects and experiments for better learning outcomes. Possibilianism is a new approach that explores the vast possibility space without committing to a specific belief system, encouraging active exploration. The book “Sum” by David Eagleman consists of 40 short stories that shine a light on the unknown possibilities in the universe, challenging traditional beliefs. Artificial neural networks lack an internal model of the world and act as statistical parrots, showing the need for further development to mimic the brain’s complexity. The field of neuroscience is expected to condense into more theoretical frameworks in the future, simplifying the vast amount of data currently available.

Highlights

• 2024-12-23 12:04 Stephen J. Dubner: According to Eagleman, the brain is constantly trying to predict the world around it. But of course, the world is unpredictable and surprising. So the brain is constantly updating its model. The capacity of our brains to be ever changing is usually referred to as plasticity. But Eagleman offers another term.

• 2024-12-23 12:09 David Eagleman: Plasticity is the term used in the field because the great neuroscientist or psychologist, actually William James, coined the term because he was impressed with the way that plastic gets manufactured, where you mold it into a shape and it holds onto that shape. And he thought, that’s kind of like what the brain does. The great trick that mother Nature figured out was to drop us into the world half baked. If you look at the way an alligator drops into the world, it essentially is pre programmed. It eats, mates, sleeps, does whatever it’s doing.

• 2024-12-23 12:09 So what you learned back in high school or college is correct most of the time. But what it overlooks is the fact that the brain is so flexible, if a person goes blind or is born blind, that part of the brain that we’re calling the visual cortex, that gets taken over by hearing, by touch, by other things. And so it’s no longer visual cortex. The same neurons that are there are now doing a totally different job.

• 2024-12-23 12:09 Stephen J. Dubner: So let me pose a question to listeners. Imagine you have a newborn baby, and he or she looks absolutely flawless on the outside. But then upon examination, the doctors discover that half of his or her brain is just missing a complete hemisphere of the brain. It’s never developed. It’s just empty space. I would expect that would be a fatal defect, or best the child would be growing up profoundly mentally disabled.

• 2024-12-23 12:05 David Eagleman: Turns out the kid will be just fine. You can be born without half the brain, or you can do what’s called a hemispherectomy, which happens to children who have something called Rasmussen’s encephalitis, which is a form of epilepsy that spreads from one hemisphere to the other. The surgical intervention for that is to remove half the brain. You can just imagine, as a parent, the horror you would feel if your child had to go in for something like that. But you know what, kids?

• 2024-12-23 12:06 Just fine. I can’t take my laptop and rip out half the motherboard and expect it to still function. But with the brain, with a live wired system, it’ll work.

• 2024-12-23 12:10 David Eagleman: So it turns out that blind people can make all kinds of sounds either with their mouth, like clicking or the tip of their cane or snapping their fingers, anything like this. And they can get really good at determining what is coming back as echoes and figure out, oh, okay, this is an open space in front of me here. There’s something in front of me. It’s probably a parked car.

• 2024-12-23 12:11 So that part of the brain is taken over by audition, by hearing, and by touch and other things. What happens is that the blind person becomes really good at these other things because they’ve just devoted more real estate to it. And as a result, they can pick up on all kinds of cues.

• 2024-12-23 12:04 But the visual system is at a disadvantage whenever the planet rotates into darkness. And so, given the rapidity with which other systems can encroach on that, what we realized is it needs a way of defending itself against takeover every single night. And that’s what dreams are about. So what happens is you have these midbrain mechanisms that simply blast random activity into the visual cortex every 90 minutes during the night. And when you get activity in the visual cortex, you say, oh, I’m seeing things.

• 2024-12-23 12:05 new theory about dreams. We studied 25 different species of primates, and we looked at the amount of REM sleep they have every night. And we also looked at how plastic they are as a species. It turns out that the amount of dream sleep that a creature has exactly correlates with how plastic they are. Which is to say, if your visual system is in danger of getting taken over because. Because your brain is very flexible, then you have to have more dream sleep. And by the way, when you look at human infants, they have tons of dream sleep at the beginning when their brains are very plastic, and as they age, the amount of dream sleep goes down.

• 2024-12-23 12:11 I got really interested in this idea of sensory substitution, which is, can you push information into the brain via an unusual channel? Originally, we built a vest that was covered with vibratory motors, and we captured sound for people who are deaf. So the vest captures sound, breaks it up from high to low frequency, and you’re feeling the sound on your torso, by the way, this is exactly what the inner ear does. It breaks up sound from high to low frequency and ships that off to the brain. So we’re just transferring the inner ear to the skin of the torso, and it worked.

• 2024-12-23 12:11 People who are deaf could come to hear the world that way. So I spun this out of my lab as a company, Neosensory, and we shrunk the vest down to a wristband, and we’re on wrists of deaf people all over the world. The other alternative for somebody who’s deaf is a cochlear implant, an invasive surgery. This is much cheaper and does as good a job.

• 2024-12-23 12:05 For people who are blind, for example, there are a few different approaches to this one is called the brain port. And that’s where for a blind person, they have a little camera on their glasses, and that gets turned into little electrical stimulation on the tongue. So you’re wearing this little electro tactile grid on your tongue and it tastes like pop rocks sort of in your mouth. Blind people can get pretty good at this. They can navigate complex obstacle courses or throw a ball into a basket at a distance, because they can come to see the world through their tongue. Which, if that sounds crazy, it’s the same thing as seeing it through these two spheres that are embedded in your skull.

• 2024-12-23 12:05 It’s just capturing photons and information about them, figuring out where the edges are and then shipping that back to the brain. And the brain can figure that out. There’s also a colleague of mine that makes an app called Voice. It uses the phone’s camera and it turns that into soundscape. So if you’re moving the camera around, you’re hearing, you know, it sounds like a strange cacophony.

• 2024-12-23 16:44 David Eagleman: Oh, you know, like, just in case you ever need to know that the Battle of hastings happened in 1066. Here you go. Stephen J. Dubner: And you want to contrast that with just in time information. David Eagleman: Exactly.

• 2024-12-27 11:25 David Eagleman: Chose because among other things, that’s the title story. In the afterlife, you relive your life, but all the moments that share a quality are grouped together. So you spend three months waiting in line and you spend 900 hours sitting on the toilet. And you spend 30 years sleeping all in a row. Exactly. And this amount of time looking for lost items, and this amount of time realizing you’ve forgotten someone’s name and this amount of time falling and so on. Part of why I use the title thumb is because of the sum of events in your life. Like that part of it was because Kojito Urgosum. So it ended up just being the perfect title for me, even if it did lose a couple of readers there. Yeah.

• 2024-12-27 11:25 But it’s not yet the brain or anything like it. It’s just taking the very first idea about the brain and running with it. What a large language model does not have is an internal model of the world world. It’s just acting as a statistical parrot. It’s saying, okay, given these words, what is the next word most likely to be? Given everything that I’ve ever read on the planet. And so it’s really good at that. But it has no model of the world, no physical model. And so things that a six year old can answer, it is stuck on. Now, this is not a criticism of it in the sense that it can do all kinds of amazing stuff and it’s going to change the world, but it’s not the brain yet.