Treating Parkinson's with Math

So... I'm back in the USofA now, after a long-ish trip to Sweden for the CNS conference. Overall, the meeting was pretty good, and there was some great science presented! On top of that, Stockholm is a gorgeous city, and well worth a visit.

One of the keynote talks at this meeting was by a German physicist-turned-neuroscientist (much like myself), on a very exciting new treatment for Parkinson's Disease.

For those of you who don't know, Parkinson's is a debilitating condition often associated with uncontrolled shaking of the limbs, and difficulty in controlling movement.

They key to treatment is the realization that Parkinson's arises from overly synchronized neural activity in the midbrain, often caused by a lack of dopamine-producing cells. Normally, neurons fire relatively asynchronously (not all at the same time), so that synchrony is a clear atypical situation.

The question is, then, can that synchrony be removed, and if so, will that restore functionality for the Parkinson's patient? Schockingly, the answer is yes!

This, on it's own, is nothing really new. In particular, a technique called deep brain stimulation (DBS) has been around for awhile, and amounts to implanting something akin to a pacemaker in the brain. While that is already a big advance in Parkinson's treatment, it's not really a cure because as soon as one turns off the pacemaker, the symptoms return, and the effectiveness of the pacemaker often decreases over time.

What Tass and his colleagues did, however, is a bit more interesting. They started by modeling the diseased condition as a set of coupled oscillators (a standard physicsy thing to do), wherein the couplings were affected by the neural activity (via STDP, a well-known form of neural plasticity that is though to underly learning and adaptation).

They then realized that, if they could co-activate subsets of these oscillators, the STDP adaptation would, over time, break those connections that were forcing the synchronous activity.

So far, I think it's a fairly neat story, but not an unusual one: a physicist sees some real-world thing and says "ah... I think that's easy to model", and writes down some equations.

However, Tass took this a bit further, and invented a device to perform that neural co-activitation, leading to a technique he calls Coordinated Reset stimulation. He got permission to implant it into some Parkinson's patients, and studied their outcomes.

The results were surprising: after only a short period of treatment, the Parkinson's symptoms were gone, and they did not return when the treatment ended (much unlike the standard DBS pacemaker treatements).

A summary of this talk is available online. I think it's a great reminder to physicists to keep tackling real-world problems, and not to stop once the equations are solved, but rather to keep pushing until the solution is implemented, or it becomes apparent that it is not implementable.