David Eagleman

She was using electrical shocks on the tongue. And there's actually another company that spun out called Lanier that does this with sounds in the ear and shocks on the tongue. They had an argument that they think it had to be touched from the head and the neck. And I didn't buy that at all. And that's why I tried that with the wristband.

So this was not an original idea for us, except to try this on the wrist. And it works equally as well.

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 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 to It's the same thing as seeing it through these two spheres that are embedded in your skull.

It's just capturing photons and information about them, figuring out where the edges are, and then shipping that back to the brain. 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.

But it doesn't take long, even for you as a sighted person, to get used to this and say, oh, okay, I'm turning the visual world into sound. And it's starting to make sense when I pass over an edge or when I zoom into something, the pitch changes, the volume changes. There's all kinds of changes in the sound quality that tells you, oh yeah, now I'm going to close something. Now I'm getting far.

And here's what the world looks like in sound. Coming up after the break. There's really no shortage of theoretical ideas in neuroscience, but fundamentally, we don't have enough data.

What they're doing is they're putting electrodes into the brain to read from and talk to the neurons there.

That is correct. Everything we've been talking about so far with sensory substitution, that's a way of pushing information in and non-invasive. And what Neuralink is, you have to drill a hole in the head to get to the brain itself, but then you can do reading and writing invasively. That actually has been going on for 60 years now. The language of the brain is electrical stimulation.

And so with a little tiny wire, essentially, you can zap a neuron and make it pop off, or you can listen to when it's chattering along, going pa-pa-pa-pa-pa-pa-pa-pa. There's nothing actually new about what Neuralink is doing, except that they're making a one-ton robot that sews the electrodes into the brain. So it can do it smaller and tighter and faster than a neurosurgeon can.

And by the way, there are a lot of great companies doing this sort of thing with electrodes. As people get access to the brain, we're finally getting to a point, we're not there yet, but we're getting to a point where we'll finally be able to push theory forward. There's really no shortage of theoretical ideas in neuroscience.

But fundamentally, we don't have enough data because, as I mentioned, you've got these 86 billion neurons all doing their thing, and we have never measured what all these things are doing at the same time.

So we have technologies like functional magnetic resonance imaging, fMRI, which measures big blobby volumes of, ooh, there was some activity there and some activity there, but that doesn't tell us what's happening at the level of individual neurons. We can currently measure some individual neurons, but not many of them.

Be like if an alien asked one person in New York City, hey, what's going on here? And then tried to extrapolate to understand the entire economy of New York City and how that's all working. So I think we're finally getting closer to the point where we'll have real data about, wow, this is what

thousands or eventually hundreds of thousands or millions of neurons are actually doing in real time at the same moment. And then we'll be able to really get progress. I actually think the future is not in things like Neuralink, but the next level past that, which is nanorobotics.

This is all theoretical right now, but I don't think this is more than 20, 30 years off, where you do three-dimensional printing, atomically precise, you make molecular robots, Hundreds of millions of these. And then you put them in a capsule and you swallow the capsule. And these little robots swim around and they go into your neurons, these cells in your brain.

And from there, they can send out little signals saying, hey, this neuron just fired. And once we have that sort of thing, then we can say non-invasively, here's what all these neurons are doing at the same time. And then we'll really understand the brain.

What we have now is EEG, electroencephalography. And there are several really good companies like Muse and Emotive that have come out with at-home methods. You just strap this thing on your head and you can measure what's going on with your brainwaves. The problem is that brainwaves are still pretty distant from the activity of 86 billion chattering neurons.

An analogy would be if you went to your favorite baseball stadium and you attached... a few microphones to the outside of the stadium and you listened to a baseball game, but all you could hear with these microphones is occasionally the crack of the bat and the roar of the crowd. And then your job is to reconstruct what baseball is just from these few little signals you're getting.

So I'm afraid it's still a pretty crude technology.