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Deep Brain Stimulation for the Minimally Conscious Part 2

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Posted on November 10, 2016 - 3:54pm

Written by Colton Smith

In April 2016 I attended the Symposium on Neuroethics hosted by the State University of New York Downstate Medical Center. Here Neurologists and Neuroscientists discussed emerging neurotechnology and how it’s being implemented. While at this conference I had the pleasure to speak with Dr. Joseph J. Fins. Fins is a physician and the E. William Davis, Jr., M.D. Professor of Medical Ethics and Chief of the Division of Medical Ethics at Weill Cornell Medical College where he is Professor of Medicine, Professor of Medical Ethics in Neurology, Professor of Health Care Policy and Research, and Professor of Medicine in Psychiatry. This is the second half of the interview.

Deep Brain Stimulation. Photo courtesy of Wikimedia Commons

Deep Brain Stimulation. Photo courtesy of Wikimedia Commons.

Colton Smith- So going to a nursing home is almost like an end of life or end state location?

Dr. Joseph J. Fins- It’s not a good place to be if you are minimally conscious. You’ve been labeled as vegetative and you’ve been categorized that way. You’re in a low acuity care center where the medical sophistication just isn’t there. You see, if somebody leaves the hospital and they are in the vegetative state, it doesn’t mean that it’s permanent until three months after anoxic brain injury and twelve months after traumatic brain injury. Before those time limits they still have the possibility of moving into the minimally conscious state over time.

Smith- So it’s possible that even though a patient has been diagnosed as vegetative and has been sent to a care facility, there’s still the possibility that they can restore consciousness over time?

Fins- They can be vegetative when they leave the hospital, but then start displaying signs of consciousness later. The problem is that you can’t do rehabilitation with these patients because they can’t follow commands.  Imagine this scenario. You had an accident six weeks ago that put you into the vegetative state and now two months later you start exhibiting signs of consciousness. The problem is that if the doctor isn’t there to see those signs then the doctor won’t realize that you’re actually minimally conscious. Another problem is that the doctor in the nursing home is unlikely to question what the expert neurologist or neurosurgeon said when you left the academic medical center where you were first treated. There are medical hierarchies and a doctor in a nursing home is not going to question the diagnosis of the professor of neurology at the medical school. But the problem is that these are not really diagnoses. They are brain states. There is an important difference there: If someone leaves the hospital with diabetes, they don’t miraculously lose their diabetes. But these are brain states we are dealing with and these states can change.

Smith- That’s very interesting because you mentioned in your talk that the brain has the potential to go back into some sort of neurodevelopmental state, similar to that of when it was developing.

Fins- We’ve had some studies that have shown that after a long period of injury and latency there may be what's called axonal sprouting. The brain makes new connections between remaining neurons that can change its functional status.

Smith- Could this axonal sprouting change the vegetative brain into a conscious one?

Fins- It can’t change you from the permanently vegetative state to the minimally conscious state, but within the minimally conscious state it may make you improve. There’s a range within the minimally conscious state. What’s fascinating to me is that in the minimally conscious state, these patients who have this axonal sprouting are basically recapitulating what we all go through as children. The brain of a child sprouts connections and hooks up the brain. We sprout connections to new areas of the brain as it develops and then prune back connections. Sprout and prune, sprout and prune. So it seems like in the setting of severe injury the brain is actually using an old familiar tool to make things better. Not right, but better.

Smith- That’s interesting that you say that because a lot of neuroscientists think that that time period goes away once you develop. What’s your opinion on that?

Fins- This process of sprouting does go down over time, but it never completely goes away. It flattens out by the time you’re in your twenties, and by the time you're my age you’re long gone! But what seems different here is that these brains are somehow chronologically altered in a way that we’ve never seen in the history of humankind. Anybody in the past that’s been this severely injured would die. Now over the last 15-20 years we’ve been managing intracranial pressures to keep patients alive. So even though you have this massive amount of injury, you can be sustained for a number of years and then go into this new state. Somehow there’s the possibility that stem cells get activated or some developmental process gets turned back on. Something is triggering these events and we don’t know how, but it’s very exciting.

Smith- That truly does sound exciting. That brings me to my next question. You mentioned in your talk that you’ve been working with deep brain stimulation (DBS). What is your opinion on DBS? I’ve heard that doctors are using DBS to stimulate the thalamus, the relay station of the brain. What is it about stimulating this area that can have an effect on these patients?

Fins- I believe that the thalamus is truly a relay station. It’s the hub in the brain that links up a circuit that my colleagues Niko Schiff and Jerome Posner have begun to describe as the Mesocircuit. This Mesocircuit is a putative theory for consciousness.

Smith- So this Mesocircuit in the brain is what is responsible for our conscious mind?

Fins- For people who have disorders of consciousness the reactivation of the Mesocircuit allows for thalamic output to the cortex to be restored, but, the thalamus not only hooks up to the cortex but also down to the brain stem. The brain stem is the part of the brain that is necessary for arousal. DBS is a way of driving thalamic output to the cortex and helping to reintegrate this circuit, which is there but dormant.

Smith- So if you stimulate the thalamus of a minimally conscious patient, will that restore some of their brain function allowing them to communicate with us?

Fins- We’ve actually done that. We published a study about it in Nature in 2007. In that study we used DBS to bilaterally stimulate a patient who could only communicate by moving an eye. After the procedure he was able to say six or seven word sentences, say the first sixteen words of the pledge of allegiance, go shopping at Old Navy, and tell his mother that he loved her. We restored his ability to communicate by using thalamic DBS.

Smith- That’s incredible. I had no idea that was possible. Do you believe that DBS is the future of medicine?

Fins- Let me put it this way, I think it’s going to be part of the future of medicine, but I think it’s a technology that we’ll probably outgrow over time as we get more sophisticated with manipulating the brain. It has taught us a lot and there’s a lot more to run through to really take advantage of this.

Smith- Is there anything else Dr. Fins?

Fins - The point that we didn’t get to, which I think is really important, is the ethics and policy issues. It is so important that we affirm the rights of people who are minimally conscious, integrate them back into civil society, and give them the opportunity to communicate with others. The reason that my colleagues and I have been so focused on restoring functional communication is that by restoring communication we both build and rebuild community. We need to bring these people back from being segregated. They are being segregated just like people were segregated in the Jim Crow south. We want to bring these people back from chronic care and allow them to reintegrate with their families and their communities. By restoring functional communication we give them the opportunity to engage with others.

We’re trying to give back people their voice. I believe that this is a civil rights issue of our generation. That’s the point that I’ve tried to get across at the end of my book Rights Come to Mind, which was just published last year by Cambridge University Press. We have to affirm the rights of these people, and all this great science isn’t going to happen unless we think it should happen. If we don’t think that these people are worthy then it won’t happen. We really need to see this as an urgent moral call to meet the needs of these people who are utterly and totally dependent on the good will of others.

Smith- That’s a very profound thought. It sounds like you believe that this is the next civil rights issue on par with the women’s rights movement, the black rights movement, or even the gay rights movement.

Fins- I do think that this in the lineage of these other rights movements. As I was finishing my book I was really struggling with the question, “Where does the Americans with Disability Act (ADA) fit into the horrible and almost scandalous way in which we treat these people”? What I realized is that the ADA law is there, but people don’t think it applies to these people. They’re not perceived as human and they don’t have the rights of citizenship. They’re just not viewed as being covered by the law.

Smith- Just because these people can’t communicate with us?

Fins- And because of the long history and overgeneralization from the vegetative state to these other people who look like them but aren’t. I have written that, “From Seneca Falls to Selma to Stonewall there was a right to vote unless you’re a woman, there was a right to education unless you’re a poor black child in the south, and there was a right to get married unless you were gay.” Over the history of time we have begun to evolve the perception that these other folks have to be included in the enfranchisement of the rights that the majority enjoy. I think that the next big civil rights hurdle is for the people who have this cognitive-motor dissociation, where their brains are more intact than their bodies reveal.

Smith- Wow, very profound statements. I’m excited for the future of neuroscience. It sounds like we’re making a lot of progress.

Fins- I appreciate being given the opportunity to talk a little bit about it.

Smith- Of course! Thank you Dr. Fins, it’s been a pleasure.

This blog post is in connection with the closed scientific workshop in partnership with the National Institutes of Health that was held to spark discussions of big, unanswered questions on how the brain and machines process patterns, aimed at understanding consciousness, intelligence, and madness. Also related is the Origins Dialogue with Johnny Depp and Lawrence Krauss on Finding the Creativity in Madness.

Read part 1 of this blog series, Deep Brain Stimulation for the Minimally Conscious Part 1

Read part 3 of this blog series, Deep Brain Stimulation for Treatment-Resistant Depression Part 1

Read part 4 of this blog seriesDeep Brain Stimulation for Treatment Resistant Depression Part 2