Deep brain stimulation as a treatment for depression.

Health and medicine explained.
Feb. 19 2008 5:24 PM

Neurostimulation

Is it a good idea to drill holes in people's heads to treat them for depression?

(Continued from Page 1)

Despite this early encouragement, there are reasons to be cautious. Parkinson's researchers were able to induce and treat tremors in animals before embarking on DBS in humans. But animal research on depression doesn't really work, because we don't know how to measure animals' mental states. That means human trials from the outset. The two major ones proceeding so far are being sponsored by companies—St. Jude Medical and Medtronic—that make the implants and so have a vested interest in the results. The legacy of psychosurgery is not exactly reassuring, either. DBS may be a far cry from the days when lobotomies robbed patients of the ability to feel emotions like love and compassion. But not long ago, patients receiving ECT suffered serious memory loss.

It's also unsettling that scientists can't account for why the patients in the small initial studies felt better—or why some showed dramatic changes and others improved only slightly or not at all (although no one got worse). Theories abound about whether the DBS voltage changes the firing pattern in the brain or affects a larger depression "circuit" that other treatments can't reach.There are no data on the long-term risks of continuous stimulation, and it's uncertain if the results could be replicated on a larger scale. "This is certainly not yet ready for prime time," says Mayberg, who has enrolled 20 more people in her study. DBS also carries a 1 percent to 2 percent risk of intracranial hemorrhage and a 5 percent to 10 percent risk of infection or a malfunctioning pacemaker. At the highest voltage, some patients temporarily felt lightheaded or mentally slow. Also, there's the potential for brain damage from gliosis (the brain's version of scar tissue), which can develop around the contact points.

Advertisement

At the same time, autopsies of Parkinson's patients who received DBS implants revealed no significant changes in the areas around the electrode contacts, according to Cleveland Clinic neurosurgeon Dr. Ali Rezai. He also points out that his depressed subjects tested the same in terms of cognitive functioning before and after getting implants. In some cases, the current even improved their memories. (Again, scientists don't know why.)

On balance, the FDA is right to move forward with this precarious research. The history of antidepressant drugs is full of examples of treatments that scientists didn't—and still don't—precisely understand and that nonetheless have brought relief to millions of people. And unlike other neurostimulation therapies for depression on the market or in development, the brain pacemaker has a track record. Some 40,000 people worldwide have undergone DBS, mostly for Parkinson's and other movement disorders. Researchers testing it for mental illness say they follow strict protocols by admitting only subjects who have tried and failed to respond to numerous rounds of drugs, psychotherapy, and ECT. In other words, like a lot of people willing to try experimental treatments, these patients have less to lose.

None of this means, however, that DBS is likely to be used to treat depression on a wide scale. Researchers currently are looking for brain markers that might flag which patients would respond best to it. The treatment also isn't a cure-all, and patients may need to supplement it with more traditional talk therapy. Meanwhile, neurologists are exploring the use of brain pacemakers to treat drug addiction, anorexia, obesity, Tourette's syndrome, and obsessive-compulsive disorder. We have to simultaneously become more comfortable with poking around in people's brains without letting ourselves forget just how mysterious and delicate this all is.

TODAY IN SLATE

Doublex

Crying Rape

False rape accusations exist, and they are a serious problem.

Scotland Learns That Breaking Up a Country Is Hard to Do

There’s a Way to Keep Ex-Cons Out of Prison That Pays for Itself. Why Don’t More States Use It?

The Music Industry Is Ignoring Some of the Best Black Women Singing R&B

How Will You Carry Around Your Huge New iPhone? Apple Pants!

Culturebox

Theo’s Joint and Vanessa’s Whiskey

No sitcom did the “Very Special Episode” as well as The Cosby Show.

Television

The Other Huxtable Effect

Thirty years ago, The Cosby Show gave us one of TV’s great feminists.

Cliff Huxtable Explains the World: Five Lessons From TV’s Greatest Dad

Why Television Needs a New Cosby Show Right Now

  News & Politics
The World
Sept. 19 2014 12:33 PM The Precarious Predicament of Russia’s Neighbors
  Business
Moneybox
Sept. 19 2014 12:09 PM How Accelerators Have Changed Startup Funding
  Life
The Vault
Sept. 19 2014 12:08 PM The CIA Used to Have a Commute-by-Canoe Club. One Member’s Memories.
  Double X
The XX Factor
Sept. 19 2014 11:33 AM Planned Parenthood Is About to Make It a Lot Easier to Get Birth Control
  Slate Plus
Slate Picks
Sept. 19 2014 12:00 PM What Happened at Slate This Week? The Slatest editor tells us to read well-informed skepticism, media criticism, and more.
  Arts
Brow Beat
Sept. 19 2014 12:10 PM Watch the Trailer for Big Eyes, a Tim Burton Movie About People With Normal-Sized Eyes
  Technology
Future Tense
Sept. 19 2014 11:40 AM Apple Invented the Perfect Way to Handle Your Giant New Phone
  Health & Science
Medical Examiner
Sept. 19 2014 12:13 PM The Most Terrifying Thing About Ebola  The disease threatens humanity by preying on humanity.
  Sports
Sports Nut
Sept. 18 2014 11:42 AM Grandmaster Clash One of the most amazing feats in chess history just happened, and no one noticed.