TEDxUCLA 2019: Time

Rewiring the brain


About Andrew 

Andrew Leuchter


Imagine that you could rewire your brain to change how you feel, think, or create. What would you like to change? Would you like to improve your mood? Be less self-critical? Improve your attention, your memory, perhaps your artistic skills?

As a professor of psychiatry at UCLA, development of new methods to enhance mind and brain health is my professional passion. In my program we essentially rewire the patient’s brains every day using a technique called neuromodulation.

Neuromodulation involves stimulating the brain using everything from an electromagnet to a 9-volt battery. The tiny electrical microcurrents these methods apply to the brain are virtually without side effects, but can have a huge impact on how we feel and think and the connections between brain cells, the wiring of the brain.

At the present time, these methods are used primarily for the treatment of illnesses such as depression. In the future, these revolutionary methods may be used to unlock human potential, to enhance how it is that we interact with the world.

There have been three revolutions in mind and brain health. The first was the psychological revolution, approximately 150 years ago. It’s hard to believe that until that time, most people believed that mental illness arose from demonic possession or a moral failing. As a result, the major treatments were punishment or confinement.

With the psychological revolution came the development of the so-called “talking cures.” We developed psychotherapies that could be used to help people deal with their feelings and thoughts and treat depression.

Second was the chemical revolution approximately 70 years ago. We made the purely fortuitous discovery that our feelings and thoughts were mediated by chemicals called neurotransmitters that sent signals from one nerve cell to the next.

Iproniazid was a tuberculosis drug being tested in a sanatorium in Europe. To the surprise of physicians, not only did the drug cure TB, it made morose patients unusually happy. Iproniazid became the first anti-depressant medication and ushered in a new era when we could correct brain chemistry to treat depression.

Anti-depressant drugs now have become among the most prescribed medications in the world, with more than one in eight Americans reporting that they take these medications every month.

Nevertheless, the problem of depression continues to grow. Depression now has emerged as the single most disabling illness in the world, for the first time surpassing cancer, heart disease, and AIDS. In the U.S. alone, one person ends his or her life from suicide every 13 minutes, about the length of my talk. We need better treatments for this devastating condition.

The neuromodulation revolution is happening now. We’ve discovered that, in addition to operating on feelings, thoughts, and chemicals, the brain operates on sending electrical signals through an array of networks. Mental illness can be thought of as a problem with the network wiring, and if we can rewire the network, we can treat the illness.

Neuromodulation too was a fortuitous discovery. A researcher in London in 1985 discovered that if he put an electromagnet on his head and activated the area of the brain that controlled his right hand, he could make his thumb twitch. Really, that is how science works. This new technique was called transcranial magnetic stimulation, or TMS.

Fast-forward a few years when scientists began to wonder, what if we activated the brain not just with one pulse of energy but a whole train of pulses? Would repetitive pulsing lead to lasting changes in brain function?

Scientists discovered that repetitive pulsing made nerve cells more plastic; that is, they sprouted new and denser connections with neighbouring nerve cells. Areas of the brain that were dormant could become activated, and areas that were overly active could be quieted down. This revolutionary new technique was called repetitive transcranial magnetic stimulation, or RTMS.

This is an RTMS device. The patient sits in a chair and a powerful electromagnet, much like what you might find in an MRI machine, is placed on the patient’s head. The magnet puts out pulses of energy that are transmitted through brain networks throughout the brain.

After a few weeks of daily treatment, areas deep in the brain that are involved in mood regulation can become activated and actually can become larger. New connections that are associated with normal mood can form. These changes can result in a resolution of all of the symptoms of depression: improved mood, better energy, sleep, and reduction in or elimination of thoughts of suicide.

So how well does this new technique work? Well about 60 percent of severely depressed patients, even those who fail to benefit from years of medication therapy, can get a substantial reduction in their depressive symptoms using RTMS, and these results can be long-lasting.

So what does the future hold for RTMS? Well as I’ve mentioned a couple of times in this talk, the most interesting discoveries in medicine sometimes are fortuitous. You can see here the area of the brain that we most commonly target first for treatment of depression. Scientists began to wonder, what else happens if we stimulate that brain area?

We found that, for example, unpleasant stimuli become less unpleasant. Patients with chronic pain, for instance, still feel the pain but it bothers them less. Patients with fibromyalgia can get a substantial reduction in their pain symptoms.

If we stimulate here, around the frontal pole of the brain, we can help relieve symptoms of obsessive compulsive disorder. We also can reduce negative self-critical thinking.

If we stimulate around the central portion of the brain, we can reduce pain symptoms throughout the body. This area also can be useful for treating some symptoms of Parkinson’s disease.

Stimulating around the auditory cortex of the brain can reduce tinnitus — the part of the brain that controls hearing — can reduce tinnitus, chronic ringing in the ears, for which there’s traditionally been no effective treatment. In addition, this can reduce auditory hallucinations in patients with schizophrenia.

Some intriguing recent results suggest that stimulating around the posterior portion of the brain can improve memory function in older adults.

All of these findings raise a very interesting question, and that is what could RTMS do for normal healthy individuals? Well as you can see, there’s a lot of real estate on the brain. That’s a scientific term. And we’re still learning what the effects of stimulation are.

I want to focus for just a moment on one particular area here, at the junction of the frontal and the temporal lobes of the brain. It turns out that stimulating this area can unlock some amazing skills that for many of us may be hidden just below the surface of our consciousness.

You see here what happens if you ask a normal healthy individual with no particular artistic skill to draw a picture of a dog. You get a stick figure that, while it’s clearly a canine, is pretty uninteresting. But what happens if you ask the same person to perform the task after stimulating this area with RTMS? Suddenly the dog shows emotion. He has a personality, looks like he’s ready to play.

You see something similar here for this drawing of a horse. At first you really can’t even tell whether it’s a horse or a mule. It’s pretty dull and lifeless. After RTMS, however, suddenly the horse is springing to life. He’s ready for action, rearing back his head.

Now I was so impressed with these results that I had my staff perform this technique on me. I am embarrassed to say that this is my drawing of a woman before RTMS. Actually it’s beyond embarrassed. Kind of like what you might see a kindergartner draw. But this is what I could do after RTMS. (laughter, applause) Thank you. Okay, I had a little help with a painting.

It turns out that stimulation of this brain area doesn’t really have to do just with artistic skills. It actually has more to do with how we see the world. In just a second, I’m going to flash a phrase on the screen. As soon as I do, I want you to look at it quickly and then raise your hand if you see a problem with it.

Okay, I see that maybe a quarter of you raised your hands. It’s not easy to see. I missed it myself the first time. A bird in the, the hand. There’s a duplicated “the.” Only about 25 percent of normal healthy individuals will catch that error on first reading. After stimulating this brain area, however, the accuracy of proofreaders in detecting errors such as these more than doubles to almost 50 percent.

Now RTMS treatment for illnesses is delivered daily for a number of weeks so that the effects of stimulation can be long-lasting. Whereas the stimulation results that I just showed you came on after a single treatment and faded in less than an hour. It does raise the interesting question of what if we were to stimulate this brain area for longer? Could we make results like these be long-lasting? And would we really want to do this?

Now RTMS treatment for illnesses is remarkably safe. We’ve performed more than 6,000 of these individual treatment sessions at UCLA every year with the major common side effect being a brief slight headache. Some patients actually have hundreds of these treatments, and they generally state that their thinking and memory improves.

Nevertheless, if we are going to get into elective brain rewiring, we have to ask ourselves: how far do we really want to go? This question is becoming even more important now as we are starting to move neuromodulation from a controlled campus clinic into the home.

There now are simple neuromodulation devices that can be used in the home that operate on a 9-volt battery. Trigeminal nerve stimulation, or TNS, was approved by the FDA just last month as the first non-medication treatment alternative for ADHD in children based on a study that we actually did here at UCLA.

You can see here a subject in another one of our studies using the TNS device for the treatment of PTSD and veterans. The patient places a small patch on his or her forehead and they stimulate their brain at night while they sleep. This is as close to a side-effect-free treatment as you can get.

Now TNS is an evidence-based treatment that is approved by the FDA. But now there are a whole host of non-regulated battery-operated devices that are kind of do-it-yourself kits that are springing up for sale on the Internet. These are not subject to FDA regulation, and they’re starting to be widely used on the basis of very little evidence.

So who are some of the people using them? Well for one, adolescent boys who believe that they can greatly enhance their performance in video games. Go figure. Students are using these to enhance their reading comprehension or their acquisition of musical skills. And at the same time that the military is studying such devices for treatment of PTSD, they also are examining them for enhancing sustained attention of drone operators in combat zones.

Now we probably all agree that using this technology to reduce human suffering is a good and noble goal. We may not agree, however, that using these techniques to enhance combat performance is a good thing.

We are just now coming to understand the potential of the neuromodulation revolution. Scientists estimate that the human brain contains some 100 trillion connections among nerve cells. That is vastly greater than the number of stars in the Milky Way galaxy. We still don’t know which of these connections can be rewired, nor what all the effects might be. We know that we can treat illnesses, and some intriguing recent results suggest that we might be able to use RTMS to enhance our feelings of spirituality or even to reduce our implicit biases. We may be able to enhance how it is that we interact with the world, maybe even make ourselves smarter. Now we just need to be smart enough to use these methods wisely. Thank you.