Adventures in Adaptive Deep Brain Stimulation

You bear the mark of the ouroboros, the sign of eternal life. And what is that circle, but the shadow of the sun itself.

— Karen Maitland

Ever get the feeling that the universe is trying to tell you something? At the beginning of this year I did not know what the symbol depicted above was called. I’m sure I had seen it many times, but never picked up its name. Then one day, while doing some research into blockchains, I saw the word – Ouroboros. That led me down a rabbit hole that landed in biosemiotics, a field of theoretical biology that asserts that all life is based on communicating and interpreting symbols. An interesting thought, epitomized in many ways by the ouroboros, a symbol of eternal rebirth, a never-ending cycle of creation, an infinite procession with no beginning and no end, a closed loop.

A couple weeks later I binge-watched again what for me was the most engaging show I had seen in years, a German sci-fi thriller called Dark. However this time through I was almost distracted by how many times an ouroboros was displayed somewhere in a scene and, without giving too much away, the role that symbol played in driving the plot forward.

After that it started popping up everywhere. On tattoos of people I passed, in images or bizarre headlines I’d flick through on the internet, even an old friend opened a company called Ourboro, a deliberate play on words.

If I were a little more spiritually inclined I am guessing I would have taken all of that as a sign from above when I started to seriously consider the most important decision I might ever have to make about myself- which type of brain surgery should I get?

As I’m sure you can imagine, this is not a decision to take lightly, as I wrote about here. However it was made a little easier when I learned that I would be able to participate in a trial testing a brand new type of adaptive deep brain stimulator, aka closed-loop deep brain stimulation.

To give a very brief explanation, current DBS systems fire a continuous stream of electricity to the implanted area. As of 2019 there had been 160,000 surgeries performed worldwide for a range of conditions but it has proven particularly useful in alleviating some of the symptoms of Parkinson’s. This next generation of adaptive DBS will be able to read brain activity and adjust firing patterns accordingly. That added feature should allow for even more benefit as the symptoms of Parkinson’s can fluctuate pretty wildly throughout the day.

For a much more detailed explanation watch this terrific presentation on aDBS from neurexplain.com.

However, I still have more questions than we have answers for. How is the brain, which is itself an ever adapting system, going to adapt to a device that is constantly adapting to it? What does it feel like when the stimulation gets turned on and off? Will the system really be able to tell what my needs are at any given moment? Will it know when I’ve taken my medication or when I am asleep? What is programming an adaptive brain stimulator like? What will the read-out from my measurements look like? And how exactly does DBS work? (Yes, we still don’t really know)

I know I am at least a bit nuts because I find myself almost giddy with anticipation about getting the chance to be part of this and see if I can answer some of those questions. I am genuinely looking forward to getting an opportunity to test out and hopefully help further refine these devices.

That said, this is invasive brain surgery. I’ll be awake through the entire four hour procedure as the surgical team cuts open my skull and methodically drills, millimeter by millimeter, through layer after layer of my cortex to get the 1.5mm electrode into the 6mm wide target that is the subthalamic nucleus. I have been told it is an experience like no other, and one that you’ll not soon want to repeat. Only that once you think you are done you are reminded that there is a second lead that needs to be inserted into the other half of your brain. This is followed by another procedure a few days later to insert a battery pack into your chest and connect wires running out of your skull through your neck down to the battery.

But wait, there’s more. Recovery is an 8-12 week process as you wait for your body to heal and adjust to these foreign contraptions while you pray no bacteria take up residence. Then there is programming the device to optimize all the different settings and parameters so that you get the most benefit, which itself can take a few months to get right before finally getting the full benefits of the procedure.

I’ve been told that if all that sounds awful, it’s because it is. This is the snake eating itself. But it’s worth it, at least according to the vast majority of people I have spoken with who have gone through this. Though it requires relying on a lot of things to go right, most of which you have no control over. First there is the skilled hands of the surgeon and the surgical protocol that has been fine tuned over time, then there are all the various sensors both implanted and worn that collect the mounds of data, then there are the machine learning algorithms that process all that information and allow the device to read and react accordingly, then there is the programming neurologist who needs to find just the right combination of settings that works for you.

I’ve come to think of neurology like an expedition to uncharted territory. The doctors and scientists are the cartographers and engineers, providing rough maps of the area and whatever tools they can to help people navigate it, but it is the individuals, with support from their families, that must ultimately walk the path, mostly by themselves.

Which is why in the end, despite all the doctors and scientists I know that would be willing to help me if they could, I turn to the patients that have come before me, my fellow adventurers into the brain, to help guide me through what I am about to experience. Though no two people will walk the same route, it is the people that have cut their way through this jungle that I have found have the most to teach and the most comfort to provide. It is an indictment on society that our health systems don’t recognize the value they have to offer.

Here is a great video featuring six such individuals who have undergone DBS. A frank discussion that covers many of the ups and downs one might experience.

Well, that’s it. This time next week I will have gone through it myself. Feeling ready to start this cycle again.