Andres Lozano – TED Talk TRANSCRIPT
One of the things I want to establish right from the start is that not all neurosurgeons wear cowboy boots. I just wanted you to know that.
So I am indeed a neurosurgeon, and I follow a long tradition of neurosurgery, and what I’m going to tell you about today is adjusting the dials in the circuits in the brain, being able to go anywhere in the brain and turning areas of the brain up or down to help our patients.
So as I said, neurosurgery comes from a long tradition. It’s been around for about 7,000 years. In Mesoamerica, there used to be neurosurgery, and there were these neurosurgeons that used to treat patients. And they were trying to — they knew that the brain was involved in neurological and psychiatric disease. They didn’t know exactly what they were doing.
Not much has changed, by the way. But they thought that, if you had a neurologic or psychiatric disease, it must be because you are possessed by an evil spirit. So if you are possessed by an evil spirit causing neurologic or psychiatric problems, then the way to treat this is, of course, to make a hole in your skull and let the evil spirit escape.
So this was the thinking back then, and these individuals made these holes. Sometimes the patients were a little bit reluctant to go through this because, you can tell that the holes are made partially and then, I think, there was some trepanation, and then they left very quickly and it was only a partial hole, and we know they survived these procedures.
But this was common. There were some sites where one percent of all the skulls have these holes, and so you can see that neurologic and psychiatric disease is quite common, and it was also quite common about 7,000 years ago.
Now, in the course of time, we’ve come to realize that different parts of the brain do different things. So there are areas of the brain that are dedicated to controlling your movement or your vision or your memory or your appetite, and so on.
And when things work well, then the nervous system works well, and everything functions. But once in a while, things don’t go so well, and there’s trouble in these circuits, and there are some rogue neurons that are misfiring and causing trouble, or sometimes they’re underactive and they’re not quite working as they should.
Now, the manifestation of this depends on where in the brain these neurons are. So when these neurons are in the motor circuit, you get dysfunction in the movement system, and you get things like Parkinson’s disease.
When the malfunction is in a circuit that regulates your mood, you get things like depression, and when it is in a circuit that controls your memory and cognitive function, then you get things like Alzheimer’s disease.
So what we’ve been able to do is to pinpoint where these disturbances are in the brain, and we’ve been able to intervene within these circuits in the brain to either turn them up or turn them down. So this is very much like choosing the correct station on the radio dial.
Once you choose the right station, whether it be jazz or opera, in our case whether it be movement or mood, we can put the dial there, and then we can use a second button to adjust the volume, to turn it up or turn it down.
So what I’m going to tell you about is using the circuitry of the brain to implant electrodes and turning areas of the brain up and down to see if we can help our patients. And this is accomplished using this kind of device, and this is called deep brain stimulation.
So what we’re doing is placing these electrodes throughout the brain. Again, we are making holes in the skull about the size of a dime, putting an electrode in, and then this electrode is completely underneath the skin down to a pacemaker in the chest, and with a remote control very much like a television remote control, we can adjust how much electricity we deliver to these areas of the brain. We can turn it up or down, on or off.
Now, about a hundred thousand patients in the world have received deep brain stimulation, and I’m going to show you some examples of using deep brain stimulation to treat disorders of movement, disorders of mood and disorders of cognition. So this looks something like this when it’s in the brain.
You see the electrode going through the skull into the brain and resting there, and we can place this really anywhere in the brain. I tell my friends that no neuron is safe from a neurosurgeon, because we can really reach just about anywhere in the brain quite safely now.
Now the first example I’m going to show you is a patient with Parkinson’s disease, and this lady has Parkinson’s disease, and she has these electrodes in her brain, and I’m going to show you what she’s like when the electrodes are turned off and she has her Parkinson’s symptoms, and then we’re going to turn it on. So this looks something like this.
The electrodes are turned off now, and you can see that she has tremor.
(Video) Man: Okay.
Woman: I can’t.
Man: Can you try to touch my finger?
Man: That’s a little better.
Woman: That side is better.
We’re now going to turn it on.
It’s on. Just turned it on. And this works like that, instantly.
And the difference between shaking in this way and not —
The difference between shaking in this way and not is related to the misbehavior of 25,000 neurons in her subthalamic nucleus. So we now know how to find these troublemakers and tell them, “Gentlemen, that’s enough. We want you to stop doing that.” And we do that with electricity.
So we use electricity to dictate how they fire, and we try to block their misbehavior using electricity. So in this case, we are suppressing the activity of abnormal neurons. We started using this technique in other problems, and I’m going to tell you about a fascinating problem that we encountered, a case of dystonia.
So dystonia is a disorder affecting children. It’s a genetic disorder, and it involves a twisting motion, and these children get progressively more and more twisting until they can’t breathe, until they get sores, urinary infections, and then they die.
So back in 1997, I was asked to see this young boy, perfectly normal. He has this genetic form of dystonia. There are eight children in the family. Five of them have dystonia. So here he is.
This boy is nine years old, perfectly normal until the age six, and then he started twisting his body, first the right foot, then the left foot, then the right arm, then the left arm, then the trunk, and then by the time he arrived, within the course of one or two years of the disease onset, he could no longer walk, he could no longer stand. He was crippled, and indeed the natural progression as this gets worse is for them to become progressively twisted, progressively disabled, and many of these children do not survive.
So he is one of five kids. The only way he could get around was crawling on his belly like this. He did not respond to any drugs. We did not know what to do with this boy. We did not know what operation to do, where to go in the brain, but on the basis of our results in Parkinson’s disease, we reasoned, why don’t we try to suppress the same area in the brain that we suppressed in Parkinson’s disease, and let’s see what happens?
So here he was. We operated on him hoping that he would get better. We did not know.
So here he is now, back in Israel where he lives, three months after the procedure, and here he is.
On the basis of this result, this is now a procedure that’s done throughout the world, and there have been hundreds of children that have been helped with this kind of surgery. This boy is now in university and leads quite a normal life. This has been one of the most satisfying cases that I have ever done in my entire career, to restore movement and walking to this kind of child.