Illustration by Alex Gamsu Jenkins

The Shocking Thing About the Brain

An electrical-stimulation technology with promising new uses comes from a dark age that still has a lot to teach us.

History does not look kindly on biological psychiatry. Beginning in the late 19th and early 20th centuries, electroshock therapy, the lobotomy, and related psychosurgeries were administered widely and liberally, until chlorpromazine, the first antipsychotic medication, was introduced in the 1950s.

We now think of this as a dark age in psychiatry, during which barbaric treatments were meted out on hundreds of thousands of patients around the world, often to devastating effect, and without consent. Most practitioners believed they were helping their patients, but the methods they employed were very crude, and they had few checks and balances, so it may be better to think of them as being misguided, rather than malicious.

What, then, should we make of deep brain stimulation, a technology that has roots in that same era?

DBS, as it’s known, is a highly invasive procedure in which ultra-thin wire electrodes are implanted, via small holes drilled through the skull, into a specified brain region. The device, sometimes referred to as a “brain pacemaker,” is powered by a small battery implanted under the skin of the chest, and emits electrical pulses that modulate brain activity in the targeted area, in ways that are still not fully understood.

Since it gained approval from the U.S. Food and Drug Administration in 2002, it has been used to treat an estimated 100,000 people with Parkinson’s disease and other movement disorders. It’s been rightly hailed as revolutionary in its ability to alleviate tremors and other Parkinson’s symptoms, and these successes have led researchers to investigate the possibility of using DBS to treat other conditions — including psychiatric disorders.

DBS is widely believed to have been developed by researchers in France in the late 1980s. But as investigative journalist Lone Frank reveals in The Pleasure Shock: The Rise of Deep Brain Stimulation and Its Forgotten Inventor, it was actually developed three decades earlier by Robert G. Heath at Tulane University.

We are about to see the emergence of what could be called precision psychosurgery.

Heath is a hugely divisive figure. On the one hand, he was a pioneering neuropsychiatrist who recognized the intimate links between mental functions and the body long before the concept of embodied cognition became trendy, and he saw brain dysfunction as the root cause of mental illness. On the other hand, he pushed the boundaries of science and ethics and often crossed those lines altogether.

The Pleasure Shock begins with an experiment in which Heath explored “the possibility of altering” the sexual orientation of a 24-year-old homosexual man “through electrical stimulation of pleasure sites of the brain,” while the participant watched pornography and spent time with a prostitute. Heath also tested the effects of LSD and the brainwashing drug bulbocapnine on unwitting African-American prisoners at Louisiana State Penitentiary, allegedly as part of the CIA’s MK-Ultra “mind-control” program that ran from the 1950s into the ’70s.

On the face of it, Heath’s story appears to parallel the life and work of the notorious Walter Freeman, who lobotomised more than 4,500 people in North America during the 1940s and early ’50s, as described by Jack El-Hai in his 2005 book, The Lobotomist. Freeman, like Heath, was highly driven, and was overzealous, or perhaps unscrupulous, in pursuing what he believed were significant breakthroughs in the treatment of mental illness. Perhaps because of the highly controversial nature of Heath’s work, his contributions and legacy were eventually all but forgotten, and Frank describes the great lengths she had to go to track down documents about Heath’s work, as well as his surviving patients and colleagues.

This brings us back to today.

The successes of using DBS to treat Parkinson’s have not been mirrored in psychiatric patients so far. That’s partly because psychiatric disorders are far more complex, presenting a constellation of symptoms rather than a well-characterized pathology. The use of DBS in psychiatry therefore remains highly experimental.

However, we are about to see the emergence of what could be called precision psychosurgery, in which DBS and various other neuromodulatory approaches will be available to treat anything from anxiety to obesity. In 2008, the FDA approved the use of DBS for treatment of obsessive-compulsive disorder, under the Humanitarian Device Exemption. And it could yet prove to be a life-saving approach for patients with treatment-resistant depression, even though a flagship trial was abruptly halted last year.

Although future generations will undoubtedly look back at today’s technologies and therapies as crude, advances in our understanding of how the brain works, coupled with continuing technological advances, will surely make these interventions increasingly precise and effective in years to come.

The ethical minefield that Heath faced, one that we still will have to navigate.

That’s why the work of Heath, Freeman, and others like them is worth understanding. It’s not merely so we can denounce those scientists as evil. We should draw on their stories to think about how to use new techniques wisely — to stick to evidence-based theories of disease and test potential new therapies rigorously while preventing the exploitation of vulnerable patients and recognizing their autonomy.

Beyond this, DBS raises other thorny questions.

When Heath fitted his homosexual patient with a device he could use to stimulate the septal region of his brain on his own, the man had “feelings of pleasure, alertness, and warmth (goodwill); he had feelings of sexual arousal and a compulsion to masturbate.” The man stimulated his own brain up to 500 times per hour, and “protested each time the unit was taken away from him, pleading to self-stimulate just a few more times,” a phenomenon also observed more recently in patients treated with DBS for both depression and OCD. And there are growing numbers of reports that DBS and other forms of brain stimulation can improve memory and even influence moral behavior, though not always for the better.

With the implantation surgery alone costing up to $50,000, use of DBS will not quickly become widespread. Eventually, though, the procedure and instruments it requires will be accessible to greater numbers of people — not just to treat disease but, possibly, also as a form of enhancement.

Could there be some risk of creating a population of “pleasure addicts” who want nothing more than to self-administer electrical pulses to the brain? And if we can use brain stimulation to manipulate morality, do we have a moral obligation to treat “bad” people? Such questions help us to delineate the ethical minefield that Heath faced, one that we still will have to navigate.

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