We could talk a little bit about what I consider really the holy grail of the nervous system, which is neuroplasticity. It's an incredible capacity of the nervous system to change its wiring, strengthen connections, weaken connections, maybe new neurons, but probably more strengthening and weakening of connections. Nowadays, we hear a lot of excitement about so-called classical psychedelics like LSD and psilocybin, which do seem to "open plasticity." They do a bunch of other things too, but through the release of neuromodulators like serotonin and so forth.

How do you think about neuroplasticity? And more specifically, what do you think the potential for neuroplasticity is in the adult, so let's say older than 25-year-old brain, with or without machines being involved? Because in your role at Neuralink and as a neurosurgeon in other clinical settings, surely you are using machines and surely you've seen plasticity in the positive and negative direction.

What do you think about plasticity? What's possible there without machines? What's possible with machines? So as you mentioned or alluded to, the plasticity definitely goes down in older brains. It is harder for older people to learn new things, to make radical changes in their behavior, to kick habits that they've had for years.

Machines aren't the obvious answer, so implanted electrodes and computers aren't the obvious answer to increase plasticity necessarily, compared to drugs. We already know that there are pharmacologics, some of the ones you mentioned, psychedelics, that have a broad impact on plasticity. It's hard to know which area of the brain would be most potent as a stimulation target for an electrode to broadly juice plasticity compared to pharmacologic agents that we already know about.

I think with plasticity, in general, you're talking about the entire brain. You're talking about altering a trillion synapses all in a similar way in their tendency to be rewirable, their tendency to be up or down weighted. An electrical stimulation target in the brain necessarily has to be focused. With a device like potentially Neuralinks, there might be a more broad ability to steer current to multiple targets with some degree of control, but you're never going to get that broad targetability with any electrodes that I can see coming in our lifetimes, say that would be coating the entire surface and depth of the brain the way that a drug can.

I think plasticity research will bear the most fruit when it focuses on pharmacologic agents. I wasn't expecting that answer, given that you're at Neuralink. Then again, I think that all of us, me included, need to take a step back and realize that while we may think we know what is going on at Neuralink in terms of the specific goals and the general goals, and I certainly have in mind, I think most people have in mind a chip implanted in the brain or maybe even the peripheral nervous system that can give people super memories or some other augmented capacity.

We really don't know what you all are doing there. For all we know, you guys are taking or administering psilocybin and combining that with stimulation. We really don't know. I say this with a tone of excitement because I think that one of the things that's so exciting about the different endeavors that Elon has really spearheaded, SpaceX, Tesla, et cetera, is that early on, there's a lot of mystique.

Mystique is a quality that is not often talked about, but it's I think a very exciting time in which engineers are starting to toss up big problems and go for it. Obviously, Elon is certainly among the best, if not the best, in terms of going really big. I mean, Mars seems pretty far to me.

Electric cars all over the road nowadays are very different than the picture a few years ago when you didn't see so many of them, rockets and so forth, and now the brain. To the extent that you are allowed, could you share with us what your vision for the missions at Neuralink are and what the general scope of missions are?

Then if possible, share with us some of the more specific goals. I can imagine basic goals of trying to understand the brain and augment the brain. I could imagine clinical goals of trying to repair things in humans that are suffering in some way, or animals for that matter. Yeah.

It's funny what you mentioned. Neuralink, and I think Tesla and SpaceX before it, end up being these blank canvases that people project their hopes and fears onto. We experience a lot of upside in this. People assume that we have superpowers in our ability to alter the way brains work, and people have terrifying fears of the horrible things we're going to do.

For the most part, those extremes are not true. We are making a neural implant. We have a robotic insertion device that helps place tiny electrodes, smaller than the size of a human hair, all throughout a small region of the brain. In the first indication that we're aiming at, we are hoping to implant a series of these electrodes into the brains of people that have had a bad spinal cord injury.

People that are essentially quadriplegic, they have perfect brains, but they can't use them to move their body. They can't move their arms or legs. Because of some high level spinal cord damage. Exactly right. And so this pristine motor cortex up in their brain is completely capable of operating a human body.

It's just not wired properly any longer to a human's arms or legs. And so our goal is to place this implant into a motor cortex and have that person be able to then control a computer. So a mouse and a keyboard, as if they had their hands on a mouse and a keyboard, even though they aren't moving their hands, their motor intentions are coming directly out of the brain into the device.

And so they're able to regain their digital freedom and connect with the world through the internet. Why use robotics to insert these chips? And the reason I ask that is that sure, I can imagine that a robot could be more precise or less precise, but in theory, more precise than the human hand.

No tremor, for instance. More precision in terms of maybe even a little micro-detection device on the tip of the blade or something that could detect a capillary that you would want to avoid and swerve around that the human eye couldn't detect. And you and I both know, however, that no two brains nor are the two sides of the same brain identical.

So navigating through the brain is perhaps best carried out by a human. However, and here I'm going to interrupt myself again and say, 10 years ago, face recognition was very clearly performed better by humans than machines. And I think now machines do it better. So is this the idea that eventually, or maybe even now, robots are better surgeons than humans are?

In this limited case, yes. These electrodes are so tiny and the blood vessels on the surface of the brain so numerous and so densely packed that a human physically can't do this. A human hand is not steady enough to grab this couple micron width loop at the end of our electrode thread and place it accurately, blindly, by the way, into the cortical surface accurately enough at the right depth to get through all the cortical layers that we want to reach.

And I would love if human surgeons were essential to this process, but very soon humans run out of motor skills sufficient to do this job. And so we are required in this case to lean on robots to do this incredibly precise, incredibly fast, incredibly numerous placement of electrodes into the right area of the brain.

So in some ways, Neuralink is pioneering the development of robotic surgeons as much as it's pioneering the exploration and augmentation and treatment of human brain conditions. Right. So as the device exists currently, as we're submitting it to the FDA, it is only for the placement of the electrodes. The robot is part of the surgery.

I or another neurosurgeon still needs to do the, you know, the more crude part of opening the skin and skull and presenting the robot a pristine brain surface to sew electrodes into. Well, surely getting quadriplegics to be able to move again, or maybe even to walk again is a heroic goal and one that I think everyone would agree would be wonderful to accomplish.

Is that the first goal because it's hard, but doable, or is that the first goal because you and Elon and other folks at Neuralink have a passion for getting paralyzed people to move again? You know, broadly speaking, you know, the mission of Neuralink is to reduce human suffering, at least in the near term.

You know, there's hope that eventually there's a use here that makes sense for a brain interface to bring AI as a tool embedded in the brain that a human can use to augment their capabilities. I think that's pretty far down the road for us, but definitely on a desired roadmap.

In the near term, we really are focused on people with terrible medical problems that have no options right now. With regard to motor control, you know, our mutual friend recently departed, Krishna Shenoy, was a giant in this field of motor prosthesis. It just so happens that his work was foundational for a lot of people that work in this area, including us.

And he was an advisor to Neuralink. That work was farther along than most other work for addressing any function that lives on the surface of the brain. The physical constraints of our approach require us currently to focus on only surface features on the brain. So we can't say, go to the really very compelling surface, deep depth functions that happen in the brain, like, you know, mood, appetite, addiction, pain, sleep.

We'd love to get to that place eventually, but in the immediate future, our first indication or two or three will probably be brain surface functions like motor control.