24 February 2009
Deep brain stimulation for depression
Sorry about the sound quality.
Schlaepfer et al (2008) Deep Brain Stimulation to Reward Circuitry Alleviates Anhedonia in Refractory Major Depression. Neuropsychopharmacology 33, 368-377.
Kamp (2009) After Long Wait, Medtronic Starts Big Depression Study. CNNmoney.com.
Visit www.iplant.eu for more information
"So I wanted to make a comment on a paper from 2008 by Schlapfer and collegues called deep brain stimulation to reward circuitry alleviates anhedonia in refractory major depression. The reason I want to comment on this paper now is that Medtronic - the largest US vendor of deep brain stimulation implants - have just decided to proceed with phase II clinical trials, involving up to 200 patients, testing this method, testing deep brain stimulation to the human reward circuitry as a method for treating depression. This is major stuff, because
"So DBS is a well established technique for treating brain dysfunction, it's been applied in tens of thousands of cases. You basically take one or two implants the size and shape of spagetthi sticks and insert them into the brain. The tips of the implants contain electrode arrays that are used to deliver current into the brain regions that have become dysfunctional.
"Now what they've done here is they've inserted these implants into the human reward circuit, specifically into the nucleus accumbens, which is a central point for generating feelings of pleasure, reward and motivation. Because one of the central features of depression is that you can't experience these things, they figured DBS in this region might be able to normalize human reward function in severely depressed patients. And IT WORKS! It works and they're now proceeding to show that it works properly in phase II clinical trials.
"Now the thing about this is that if deep brain stimulation applied to the human reward circuit becomes fairly standard treatment so that tons of papers are written on it; so that doctors, surgeons, people all over the world become comfortable and knowledgeable about how to apply DBS to the human reward circuit then eventually it will become blindingly clear that this could be used as an iplant; that this could be used as a brain implant that delivers rewarding brain stimulation if you perform some pre-defined behavior, such as exercise in morbidly obese patients. The very same surgical procedure they use here could be used as a treatment for, say, morbid obesity in patients that can't get themselves to exercise as much as they should. They could be given rewarding brain stimulation as a motivator. But of course it doesn't stop there - it could be used to motivate ANY behavior that's sufficiently simple, that can be defined operationally so that you can attach a specific electrical reward to it. Any behavior - learning, different elements of research - could be motivated in this way. So it's an opportunity for billions of people who feel that they cannot live life the way they would like to: people who severely lack self-discipline, for them this would be a way out. To me at least this seems very very crucial."