Whenever I see news about deep brain stimulation, I perk up. The procedure – in which electrodes are implanted deep in the brain to deliver regular pulses of current – is used to treat people like my mother with movement disorders such as Parkinson’s disease or epilepsy. Researchers are also looking into whether it could be used to treat depression, but results on that front have been decidedly mixed.
That’s one reason this story published by MIT Technology Review caught my eye. Neuroscientists have discovered a “mood decoder” — a way to gauge a person’s mood simply by looking at their brain activity for the first time — that could improve deep brain stimulation for depression. The research was recently presented at the annual meeting of the Society for Neuroscience.
Unlike Parkinson’s, depression is something we still don’t fully understand from a purely neurological perspective. It’s hard to figure out which brain regions are associated with depression, since there are so many symptoms, and so it’s challenging to figure out exactly what to stimulate.
After analyzing the brain recordings of three of the five volunteers, neuroscientists found that a brain region called the cingulate cortex darted one way when a patient felt better and the other way when he felt low. The pattern was the same in all three volunteers.
In other words, they really could to see where some of the depressive symptoms originated in an area common to all three people.
“This is the first demonstration of successful and consistent human mood decoding in these brain regions,” said Sameer Sheth, who is leading the trial and is a neurosurgeon at Baylor College of Medicine.
Of course, as with many depression treatments, what works for one person doesn’t always work for another. DBS and the trial itself clearly have several drawbacks. For starters, it’s a quantum leap to conclude that it will work for the millions of people who suffer from depression if you’ve just studied a few people. However, that’s something the neuroscientists are aware of – in fact, they don’t even plan to replicate the procedure on more than just a few people. Instead, Sheth and his team try to find patterns they can use to make DBS more effective. To that end, they have since implanted electrodes in four other people with major depression and now plan to study 12 in total.
Of course, for another, as you can imagine, it’s very risky to have a hole drilled into your head, probed, and then sent electricity to different parts of your brain. It is also expensive and can cost, an average of $22,802.
But it’s a good baby step forward. Sheth and his team are already beginning to identify a few trends that could be helpful in improving DBS and understanding depression. And just as importantly, to me at least, their work takes us one step further in destigmatizing a condition that many still believe is all “in your head” – which technically it is, but now there may be a way for us to see it.
