Deep Brain Stimulation for Mental Illnesses Raises Ethical Concerns
Imagine that you are one of the hundreds of millions of people who suffer from depression. Medication hasn't helped you, so you're looking for another treatment option. Something powerful enough to change your mood as soon as you need a lift.
"If a participant experiences a personality change, does this change who they are or dehumanize them by altering their nature?"
Enter deep brain stimulation: a type of therapy in which one or more electrodes are inserted into your brain and connected to a surgically implanted, battery-operated medical device in your chest. This device, which is approximately the size of a stopwatch, sends electric pulses to a targeted region of your brain. The idea is to control a variety of neurological symptoms that can't be adequately managed by drugs.
Over the last twenty years, deep brain stimulation, known as DBS, has become an efficient and safe alternative for the treatment of chronic neurological diseases such as epilepsy, Parkinson's disease and neuropathic pain. According to the International Neuromodulation Society, there have been more than 80,000 deep brain stimulation implants performed around the world.
The Food and Drug Administration approved DBS as a treatment for essential tremor and Parkinson's in 1997, dystonia in 2003 and obsessive compulsive disorder in 2009. Since doctors can use drugs and treatments "off-label" (not approved by the FDA) to treat patients with any disease, DBS is now also being investigated as a treatment for chronic pain, PTSD and major depression.
And these new applications are raising profound ethical questions about individuality, personality, and even what it means to be human.
"These patients are essentially having a computer that can modify and influence emotional processing, mood and motor outputs inserted into the brain," said Gabriel Lazaro-Munoz, an assistant professor at The Center for Medical Ethics and Health Policy at Baylor College of Medicine. "These responses define us as human beings and dictate our autonomy. If a participant experiences a personality change, does this change who they are or dehumanize them by altering their nature? These are some of the questions we have to consider."
"When we are not in control of ourselves, are we ourselves?"
The U.S. government has similar concerns about DBS. The National Institutes of Health recently awarded grants to study the neuroethical issues surrounding the use of DBS in neuropsychiatric and movement disorders and appropriate consent for brain research. The grants are part of the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Walter Koroshetz, director of NIH's National Institute of Neurological Disorders and Stroke said, "Neuroscience is rapidly moving toward a new frontier of research on human brains that may have long-lasting and unforeseen effects. These new awards signal our commitment to research conducted in a responsible way as to anticipate all potential consequences, and to ensure that research subjects have a clear understanding of the potential benefits and risks of participating in studies."
Dr. Lazaro-Munoz's Center was awarded one of the grants to identify and evaluate the ethical, legal and social concerns with adaptive deep brain stimulation (aDBS) technologies. Adaptive DBS is a relatively new version of the technology that enables recording of brain cell activity that is then used to regulate the brain in real time. He and his team will closely observe researchers conducting aDBS studies and administering in-depth interviews to trial participants, their caregivers, and researchers, as well as individuals who declined to participate in such studies. The goal is to gain a better understanding of the ethical concerns at stake in order to guide responsible research.
Dr. Lazaro-Munoz said one of the concerns is dehumanization. "By using this technology are we compromising what makes us human? When we are not in control of ourselves, are we ourselves?" He notes that similar concerns were raised about pharmaceutical treatments for illnesses. "Both change behaviors and emotional processing. However, there is a difference. Culturally we are more used to using drugs, not implanting devices into brain and computer interfaces. Many people think of it as science fiction."
The changes in behavior due to DBS can be dramatic, perhaps none more so than with Parkinson's disease; patients may see their chronic tremors suddenly vanish.
Pills for OCD and depression take longer than DBS to see significant improvement, sometimes months. "A DBS device is either on or off. And patients and families see changes immediately," Dr. Lazaro-Munoz said. "Family members are often startled by these changes, as are the patients." He's observed that patients feel more in control with pills because they can alter and "play" with the dose or even skip a dose.
The changes in behavior due to DBS can be dramatic, perhaps none more so than with Parkinson's disease; patients may see their chronic tremors suddenly vanish, like in this must-see video.
But surgical procedures to treat motor symptoms are also increasingly being implicated as a cause of behavioral changes, both positive and negative, in patients with Parkinson's. The personality changes reported in patients who undergo DBS include hypermania, pathological gambling, hypersexuality, impulsivity and aggressiveness. One patient who suffered from OCD fell in love with the music of Johnny Cash when his brain was stimulated. On the positive side, patients report memory enhancement.
One patient who is pleased with DBS is Greg Barstead, who was diagnosed with Parkinson's in 2003, when he was the president of Colonial Penn Life Insurance Company. He also has dystonia, which affects his neck and shoulders. Barstead said that DBS has been helpful for a range of symptoms: "My shoulder is a lot less stiff and my neck hurts less. And my tremors are under control. It is not perfect, as it doesn't relieve all the Parkinson's symptoms, but it does enough of a good job that both my wife and I are very happy I had DBS."
"We are not exactly sure what part of the brain causes depression. Doctors have not identified where to implant the device."
He said he hasn't noticed any personality changes, but noted that the disease itself can cause such changes. In fact, studies have shown that it can cause many psychiatric problems including depression and hallucinations. And, approximately a third of Parkinson's patients develop dementia.
Arthur L. Caplan, founding head of the Division of Medical Ethics at NYU School of Medicine, notes that unlike psychosurgery, DBS can be turned on and off and the device can be removed. "There are less ethical concerns around treating patients with Parkinson's disease than other illnesses because surgeons know exactly where to implant the device and have many years of experience with it," he said, adding that he is concerned about using DBS for other illnesses, such as depression. "We are not exactly sure what part of the brain causes depression. Doctors have not identified where to implant the device. And I would certainly not advocate its use in patients with mild depression."
Dr. Lazaro-Munoz said of the personality changes possible with DBS, physicians need to consider how the patients were functioning without it. "Patients who are candidates for DBS typically used many medications as well as psychotherapy before opting for DBS," he explained. "To me, the question is what is the net result of using this technology? Does the patient have regrets? Are the changes in personality significant or not? Although most DBS patients report being happy they underwent the procedure, some say they don't feel like themselves after DBS. Others feel they are more like themselves, especially if there are dramatic improvements in movement problems or relief of OCD symptoms."
And then there is the question of money. The costs of DBS are covered by most insurance companies and Medicare only for FDA-approved targets like Parkinson's. Off-label uses are not covered, at least for now.
Caplan reminds people that DBS devices are manufactured by companies that are interested in making money and the average cost per treatment is around $50,000. "I am interested in seeing DBS move forward," he said. "But we must be careful and not allow industry to make it go too fast, or be used on too many people, before we know it is effective."
If you look back on the last century of scientific achievements, you might notice that most of the scientists we celebrate are overwhelmingly white, while scientists of color take a backseat. Since the Nobel Prize was introduced in 1901, for example, no black scientists have landed this prestigious award.
The work of black women scientists has gone unrecognized in particular. Their work uncredited and often stolen, black women have nevertheless contributed to some of the most important advancements of the last 100 years, from the polio vaccine to GPS.
Here are five black women who have changed science forever.
Dr. May Edward Chinn
Dr. May Edward Chinn practicing medicine in Harlem
George B. Davis, PhD.
Chinn was born to poor parents in New York City just before the start of the 20th century. Although she showed great promise as a pianist, playing with the legendary musician Paul Robeson throughout the 1920s, she decided to study medicine instead. Chinn, like other black doctors of the time, were barred from studying or practicing in New York hospitals. So Chinn formed a private practice and made house calls, sometimes operating in patients’ living rooms, using an ironing board as a makeshift operating table.
Chinn worked among the city’s poor, and in doing this, started to notice her patients had late-stage cancers that often had gone undetected or untreated for years. To learn more about cancer and its prevention, Chinn begged information off white doctors who were willing to share with her, and even accompanied her patients to other clinic appointments in the city, claiming to be the family physician. Chinn took this information and integrated it into her own practice, creating guidelines for early cancer detection that were revolutionary at the time—for instance, checking patient health histories, checking family histories, performing routine pap smears, and screening patients for cancer even before they showed symptoms. For years, Chinn was the only black female doctor working in Harlem, and she continued to work closely with the poor and advocate for early cancer screenings until she retired at age 81.
Alice Ball
Pictorial Press Ltd/Alamy
Alice Ball was a chemist best known for her groundbreaking work on the development of the “Ball Method,” the first successful treatment for those suffering from leprosy during the early 20th century.
In 1916, while she was an undergraduate student at the University of Hawaii, Ball studied the effects of Chaulmoogra oil in treating leprosy. This oil was a well-established therapy in Asian countries, but it had such a foul taste and led to such unpleasant side effects that many patients refused to take it.
So Ball developed a method to isolate and extract the active compounds from Chaulmoogra oil to create an injectable medicine. This marked a significant breakthrough in leprosy treatment and became the standard of care for several decades afterward.
Unfortunately, Ball died before she could publish her results, and credit for this discovery was given to another scientist. One of her colleagues, however, was able to properly credit her in a publication in 1922.
Henrietta Lacks
onathan Newton/The Washington Post/Getty
The person who arguably contributed the most to scientific research in the last century, surprisingly, wasn’t even a scientist. Henrietta Lacks was a tobacco farmer and mother of five children who lived in Maryland during the 1940s. In 1951, Lacks visited Johns Hopkins Hospital where doctors found a cancerous tumor on her cervix. Before treating the tumor, the doctor who examined Lacks clipped two small samples of tissue from Lacks’ cervix without her knowledge or consent—something unthinkable today thanks to informed consent practices, but commonplace back then.
As Lacks underwent treatment for her cancer, her tissue samples made their way to the desk of George Otto Gey, a cancer researcher at Johns Hopkins. He noticed that unlike the other cell cultures that came into his lab, Lacks’ cells grew and multiplied instead of dying out. Lacks’ cells were “immortal,” meaning that because of a genetic defect, they were able to reproduce indefinitely as long as certain conditions were kept stable inside the lab.
Gey started shipping Lacks’ cells to other researchers across the globe, and scientists were thrilled to have an unlimited amount of sturdy human cells with which to experiment. Long after Lacks died of cervical cancer in 1951, her cells continued to multiply and scientists continued to use them to develop cancer treatments, to learn more about HIV/AIDS, to pioneer fertility treatments like in vitro fertilization, and to develop the polio vaccine. To this day, Lacks’ cells have saved an estimated 10 million lives, and her family is beginning to get the compensation and recognition that Henrietta deserved.
Dr. Gladys West
Andre West
Gladys West was a mathematician who helped invent something nearly everyone uses today. West started her career in the 1950s at the Naval Surface Warfare Center Dahlgren Division in Virginia, and took data from satellites to create a mathematical model of the Earth’s shape and gravitational field. This important work would lay the groundwork for the technology that would later become the Global Positioning System, or GPS. West’s work was not widely recognized until she was honored by the US Air Force in 2018.
Dr. Kizzmekia "Kizzy" Corbett
TIME Magazine
At just 35 years old, immunologist Kizzmekia “Kizzy” Corbett has already made history. A viral immunologist by training, Corbett studied coronaviruses at the National Institutes of Health (NIH) and researched possible vaccines for coronaviruses such as SARS (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Syndrome).
At the start of the COVID pandemic, Corbett and her team at the NIH partnered with pharmaceutical giant Moderna to develop an mRNA-based vaccine against the virus. Corbett’s previous work with mRNA and coronaviruses was vital in developing the vaccine, which became one of the first to be authorized for emergency use in the United States. The vaccine, along with others, is responsible for saving an estimated 14 million lives.On today’s episode of Making Sense of Science, I’m honored to be joined by Dr. Paul Song, a physician, oncologist, progressive activist and biotech chief medical officer. Through his company, NKGen Biotech, Dr. Song is leveraging the power of patients’ own immune systems by supercharging the body’s natural killer cells to make new treatments for Alzheimer’s and cancer.
Whereas other treatments for Alzheimer’s focus directly on reducing the build-up of proteins in the brain such as amyloid and tau in patients will mild cognitive impairment, NKGen is seeking to help patients that much of the rest of the medical community has written off as hopeless cases, those with late stage Alzheimer’s. And in small studies, NKGen has shown remarkable results, even improvement in the symptoms of people with these very progressed forms of Alzheimer’s, above and beyond slowing down the disease.
In the realm of cancer, Dr. Song is similarly setting his sights on another group of patients for whom treatment options are few and far between: people with solid tumors. Whereas some gradual progress has been made in treating blood cancers such as certain leukemias in past few decades, solid tumors have been even more of a challenge. But Dr. Song’s approach of using natural killer cells to treat solid tumors is promising. You may have heard of CAR-T, which uses genetic engineering to introduce cells into the body that have a particular function to help treat a disease. NKGen focuses on other means to enhance the 40 plus receptors of natural killer cells, making them more receptive and sensitive to picking out cancer cells.
Paul Y. Song, MD is currently CEO and Vice Chairman of NKGen Biotech. Dr. Song’s last clinical role was Asst. Professor at the Samuel Oschin Cancer Center at Cedars Sinai Medical Center.
Dr. Song served as the very first visiting fellow on healthcare policy in the California Department of Insurance in 2013. He is currently on the advisory board of the Pritzker School of Molecular Engineering at the University of Chicago and a board member of Mercy Corps, The Center for Health and Democracy, and Gideon’s Promise.
Dr. Song graduated with honors from the University of Chicago and received his MD from George Washington University. He completed his residency in radiation oncology at the University of Chicago where he served as Chief Resident and did a brachytherapy fellowship at the Institute Gustave Roussy in Villejuif, France. He was also awarded an ASTRO research fellowship in 1995 for his research in radiation inducible gene therapy.
With Dr. Song’s leadership, NKGen Biotech’s work on natural killer cells represents cutting-edge science leading to key findings and important pieces of the puzzle for treating two of humanity’s most intractable diseases.
Show links
- Paul Song LinkedIn
- NKGen Biotech on Twitter - @NKGenBiotech
- NKGen Website: https://nkgenbiotech.com/
- NKGen appoints Paul Song
- Patient Story: https://pix11.com/news/local-news/long-island/promising-new-treatment-for-advanced-alzheimers-patients/
- FDA Clearance: https://nkgenbiotech.com/nkgen-biotech-receives-ind-clearance-from-fda-for-snk02-allogeneic-natural-killer-cell-therapy-for-solid-tumors/Q3 earnings data: https://www.nasdaq.com/press-release/nkgen-biotech-inc.-reports-third-quarter-2023-financial-results-and-business