It’s a dreadful and daunting list. It evokes a universe of suffering even as it speaks to the promise inherent in every successful DBS procedure: If we can do this, then perhaps we can do that. Faced with the challenge to take DBS further, Okun and Foote offer a measured view of the state of their art. “Right now, our understanding of the circuitry in the brain is fairly rudimentary,” says Foote. The technology is “pretty crude,” especially when compared with the human brain, with its 100 billion neurons and an estimated 100 trillion synapses.
In the past, Okun explains, the big debate in the field was whether DBS worked by inhibiting abnormal circuits or exciting other brain activity. Both sides ended up being right: The neurons closest to the implanted leads are inhibited by the electrical current, while axons leading away from the targeted cells are stimulated. In addition to these changes, says Okun, in the last few years we’ve learned that DBS also alters brain chemistry and blood flow, and even leads to the growth of new brain cells. And recent studies using electroencephalography show that DBS causes what Okun calls “neurological oscillations,” disease-specific changes in the electrical wave patterns that ripple through the brain. In Parkinson’s disease, for example, DBS suppresses the beta wave, while in Tourette’s syndrome, it stimulates the gamma wave.
Okun and Foote have seen firsthand the power of their “pretty crude” technology to affect mood and emotion. They even filmed it and presented it to an audience as part of a talk they gave in 2012. In the video, a woman undergoing a DBS operation to alleviate her debilitating obsessive-compulsive disorder beams with joy and laughs when, during the normal course of the successful procedure, Okun and Foote “tickle” a region near her nucleus accumbens, a part of the brain associated with pleasure, reward, motivation and other complex phenomena.
“Describe what you’re feeling right now,” Okun says. With an ecstatic smile on her face, in a voice giddy with joy, the woman replies, “I feel happy.”
It’s an extraordinary moment, and a powerful demonstration of DBS’s potential as a treatment for disorders like major depression. It’s also unsettling, a peek into a possible future where human happiness is the product not of the experiences and relationships that make up a life, not even of mood-altering medications, but of an elective surgical procedure, a face-lift for the brain.
Okun and Foote are acutely aware of the ethical issues raised by their DBS work. They have adopted a guiding principle that defines their goals and proscribes anything that might be considered outside the bounds of proper medical practice: The purpose of DBS, they insist, is to alleviate pain and suffering. It’s a clear standard. The question is, will it endure over time as the specialty continues to evolve?
Standing just outside the OR after Rodney Haning’s operation, still in his scrubs, his surgical mask dangling from his neck, Foote tries to imagine a day when healthy, normal people will choose to undergo DBS in order to enhance their lives. He understands the appeal. Referring to early results from Alzheimer’s research, he says, “What if we were able to make people remember better? Who’s not going to want that?”
But it’s still brain surgery, he argues. “Can you imagine,” he says, “if I take a perfectly normally functioning human being who wants to have some enhancement, and I do an operation, and I hurt them, and they end up a not perfectly normally functioning human being? Imagine the liability there.” He can’t see how the surgical boards and the FDA would ever allow such a thing. Of course, “If it ever got to the point where it was essentially risk-free,” he says, “then you would let the line go a little further, probably.”
Foote ponders that idea as the subject of cosmetic surgery comes up. Sixty years ago, plastic surgery, a technically challenging specialty with one of the longest training regimens in medicine, was centered on the treatment of facial trauma and disfigurement. Today, ordinary people think nothing about undergoing multiple cosmetic procedures to make themselves more attractive, and surgeons are happy to perform them.
“That’s actually a really good analogy,” Foote says. “I hadn’t thought of it that way. If you’re not dysfunctional, should you be able to get functional surgery? And I think DBS is going to be a similar battleground.” He hesitates a moment, then finishes the thought. “And we will ultimately cave in. Just like we did with cosmetic surgery.” This is a revelation for him, and not a good one. “I hadn’t really gone that far in my head, but now that I think about the whole cosmetic surgery thing... yeah... goddamn.”
Foote returns from the future and his mood brightens immediately when he’s asked how it feels to watch patients like Haning leave the OR smiling and waving their tremor-free hands. “It’s still a rush,” he says, “every single time.”
A few days after his operation, Rodney Haning is back home in the Villages, the Florida golf community where he lives with his wife, Barbara Jo. He’s been practicing in his den with his favorite putter, looking forward to a busy spring and summer playing the game he loves. He’s tired from the surgery, but feels stronger every day. His tremor is gone, and he hasn’t experienced any side effects from the ongoing treatment. Except for the small scars on the top of his head (his golf hat will cover them when he’s back on the course), there are no signs of his recent adventure in the OR. “I’ve got absolute trust in those guys,” he says of Okun and Foote. “I thought it was real neat during the operation when he said ‘That’s your tremor right there.’ It’s surreal, that’s why I was chuckling every now and then.” He pauses, recalling the details. Then, with a laugh: “There was a hole in my head.”