A patient undergoes deep-brain stimulation at the National Neurology Institute in Budapest, Hungary.Bernadett Szabo / Reuters
The Pleasure Shock: The Rise of Deep-Brain Stimulation and Its Forgotten Inventor by Lone Frank

It is a good question, but I was a little surprised to see it as the title of a research paper in a medical journal: “How Happy Is Too Happy?”

Yet there it was in a publication from 2012. The article was grappling with the issue of how we should deal with the possibility of manipulating people’s moods and feelings of happiness through brain stimulation. If you have direct access to the reward system and can turn the feeling of euphoria up or down, who decides what the level should be? The doctors or the person whose brain is on the line?

The authors were asking this question because of a patient who wanted to decide the matter for himself: a 33-year-old German man who had been suffering for many years from severe OCD and generalized anxiety syndrome. A few years earlier, his doctors had implanted electrodes in a central part of his brain’s reward system—namely, the nucleus accumbens. Electrically stimulating the patient’s brain had worked rather well on his symptoms, but now it was time to change the stimulator battery.

The patient went to the emergency room at a hospital in Tübingen to get everything fixed. There, they called in a neurologist named Matthis Synofzik to set the stimulator in a way that optimized its parameters. The two worked keenly on the task, and Synofzik experimented with settings from one to five volts. At each setting, he asked the patient to describe his feeling of well-being or happiness and his anxiety. The patient replied on a scale from one to 10.

The two began with a single volt. Not much happened. The patient’s well-being or “happiness level” was down around two, while his anxiety was up at eight. With another volt, his happiness level crawled up to three, and his anxiety fell to six. That was better but still nothing to write home about. At four volts, on the other hand, the picture was entirely different. The patient now described a feeling of happiness all the way up to the maximum of 10 and a total absence of anxiety.

“It’s like being high on drugs,” he told Synofzik. The neurologist turned up the voltage one more notch for the sake of the experiment, but at five volts the patient said that the feeling was “fantastic but a bit too much.” He had a feeling of ecstasy that was almost out of control, which made his sense of anxiety shoot up to seven.

The two agreed to set the stimulator at three volts, which left the patient at a “normal” level of happiness and anxiety, and would not exhaust the $5,000 battery too quickly. But the next day, when the patient was to be discharged, he went to Synofzik and asked whether they might not turn the voltage up anyway before he went home. He felt fine, but he also felt that he needed to be a “little happier” in the weeks to come. The neurologist refused. The patient finally gave in and went home in his median state with an agreement to return for regular checkups.

“It is clear that doctors are not obligated to set parameters beyond established therapeutic levels just because the patient wants it,” Synofzik and his two colleagues wrote in their article. After all, patients “don’t decide how to calibrate a heart pacemaker.”

It seems the unknown young man with accumbens electrodes didn’t buy the argument because, after a short time, he stopped coming in for checkups and vanished without a trace. Maybe he found another doctor who was willing to make him happy.

In 2005, the American neurologist Helen Mayberg and the Canadian surgeon Andres Lozano published the first study of deep-brain stimulation for the treatment of severe chronic depression—the kind of depression that does not respond to anything: not medicine, not combinations of medicine and psychotherapy, not electric shock. Yet six patients on whom everyone had given up suddenly got better.

“It’s not my job as a neurologist to make people happy.” Helen Mayberg let her statement hang in the air between us before she continued. “I liberate my patients from pain and counteract the progress of disease. I pull them up out of a hole and bring them from minus 10 to zero, but from there the responsibility is their own. They wake up to their own lives and to the question: Who am I?”

Mayberg focused on a little area of the cerebral cortex with a gnarly name, the area subgenualis or Brodmann area 25. It is located near the base of the brain almost exactly behind the eye sockets. Here, it is connected not only to other parts of the cortex, but to parts of the reward system and of the limbic system, brain regions involved with our motivation, our experience of fear, our learning abilities and memory, libido, regulation of sleep, appetite—everything that is affected when you are clinically depressed.

Mayberg’s first patient treated with deep-brain stimulation had her operation on May 13, 2003. The patient was told that there were no particular expectations, and was asked to report everything she observed.

The team began with their lowest-placed electrical contact. Nothing happened, even when they turned up the voltage. Then they went on to the next contact a half-millimeter higher in the tissue. Even though they were only at six volts, the patient suddenly spoke, telling Mayberg she was feeling “a sudden feeling of great, great calm ... like when it’s been winter, and you have just had enough of the cold, and you go outside and discover the first little shoots and know that spring is finally coming.”

Mayberg’s patients “are aware I have not given them anything but have removed something that was bothering them,” she said. She liked analogies and offered me one. “It is like having one foot on the accelerator and one foot on the brake at the same time and, then, lifting your foot off the brake. Now, you can move.”

Mayberg related the story of a patient to me. This woman had an alcohol problem in the past and, after she had her electrodes installed, she went home and waited for them to give her a sense of intoxication or euphoria. She was completely paralyzed by her expectations, and Mayberg had to explain that there was nothing to wait for. The procedure had simply awakened the lady to the realities of her life. The symptoms of her disease were diminished, but she herself had to put something in their place if she wanted to fill her life.

“Our nervous system is set up to want more and to go beyond the boundaries we run into,” Mayberg said. “You don’t want just one pair of shoes, right? I fundamentally believe that you go into people’s brains in order to repair something that is broken, but there is something strangely naïve about wanting to stimulate the brain’s reward system. Ask any expert on addiction. You will wind up with people who demand more and more current.”

The journal Pain described such a case of dependence on deep-brain stimulation way back in 1986. In order to relieve insufferable chronic pain, a middle-aged American woman had a single electrode placed in a part of her thalamus on the right side. She was also given a self-stimulator, which she could use when the pain was too bad. She could even regulate the parameters of the current. She quickly discovered that there was something erotic about the stimulation, and it turned out that it was really good when she turned it up almost to full power and continued to push on her little button again and again.

In fact, it felt so good that the woman ignored all other discomforts. Several times, she developed atrial fibrillations due to the exaggerated stimulation, and over the next two years, for all intents and purposes, her life went to the dogs. Her husband and children did not interest her at all, and she often ignored personal needs and hygiene in favor of whole days spent on electrical self-stimulation. Finally, her family pressured her to seek help. At the local hospital, they ascertained, among other things, that the woman had developed an open sore on the finger she always used to adjust the current.


This post is adapted from Frank's new book, The Pleasure Shock: The Rise of Deep-Brain Stimulation and Its Forgotten Inventor.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.