Inside a neuroscientist’s quest to cure coma
By Ross Pomeroy | Published: 2025-04-21 14:30:00 | Source: Neuropsych – Big Think
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The study of consciousness is a field crowded with scientists, philosophers, and educators. But neuroscientist Daniel Tucker focuses on a shadow twin: the unconscious.
His path to this research began with a tragedy he witnessed firsthand. While at a music festival, a young concert-goer near Tucker dove headfirst into a shallow lake. He quickly appeared, his body limp and still. Tucker and others rushed to help. He performed CPR, but it quickly became apparent that the young man’s neck had been broken. There was nothing to be done.
“This was a very strange experience as he watched his consciousness disappear from existence,” Tucker tells Big Think. “I was confused. Here was this person, this body, this brain, and something was missing.”
“Not only was it really ambiguous, it was very important from an ethical and medical standpoint, because that’s the thing where we place all our moral values; that’s character.”
Tucker was in graduate school at the time, and was already interested in consciousness and the neuroscience behind it. Losing consciousness was only on his radar as a way to further clarify consciousness. It was something consistent and measurable in a field that is often philosophical rather than empirical. But his direct encounter with death stimulated a new focus on the unconscious itself, and a desire to move into medical and translational research. Tucker couldn’t save this young man from permanent unconsciousness, but perhaps he could save others.
Hidden prisons
Now 33, Tucker is a postdoctoral fellow in the UCLA Department of Neurology. Outside of the lab, he puts a lot of effort into his physical and mental health, exercising regularly and journaling daily, pausing to think about things he’s grateful for. Within the lab, he focuses on the neurobiology of the unconscious: what happens in the unconscious brain? In this endeavor, he examines brain organoids in petri dishes, analyzes the flow of information in the brain, and uses deep learning artificial intelligence to explore differences in electrical activity between the conscious and unconscious brain.
Tucker points out that endeavors to understand consciousness and the unconscious are deeply intertwined, but the latter rests on a more empirical foundation.
“Thinking about losing consciousness is more scientifically and medically treatable,” Tooker explains. “Consciousness is a really ill-defined concept. As someone who has been thinking about this scientifically for a while, I still don’t know what it really means to be conscious. I can’t describe it to you clearly. It’s a lot easier for me to say what it means to be unconscious. And obviously something changes in the brain when we’re unconscious. It’s a common endpoint for a lot of different things, like deep sleep, generalized seizures, and anesthesia, so scientific study is not only easier, it’s medically important.” Also.
This medical importance is what drives Tucker now. Perhaps its greatest goal is to treat coma and other disorders of consciousness, such as the vegetative state. Coma, a deep, prolonged state of unconsciousness from which a person cannot awaken, affects 258 out of every 100,000 Americans each year. Stroke, COVID-19, cardiac arrest, and traumatic brain injury are common causes. Many of these people live in either a coma or a minimally conscious state, where they are fully “awake” but unaware, or only minimally aware of their surroundings. As many as 300,000 Americans live in this gray area of consciousness. Those trapped in this fog are often referred to as being “in a coma.”
“Because vegetative patients aren’t really able to engage in the world, I think they’re kind of hidden away,” Tucker says. “I could have driven by some of these people’s homes, and I would never have guessed that there was a patient locked inside and basically tied to a bed who couldn’t move. Because they’re invisible. They can’t get out and walk. They can’t defend themselves. You could walk by them all the time, and you’d have no idea.”
Disturbances of consciousness can be devastating. Tucker says that these diseases do not only consume the lives of those directly affected.
“They’re being cared for by their loved ones. They have to be on a feeding tube. They can’t use the bathroom.”
Coma treatment
So, how can medical research free those imprisoned by unconsciousness? Tucker has several ideas.
One such experiment that is still in its early stages is modeling disorders of consciousness in brain organoids: small structures of brain cells grown in petri dishes of stem cells. If researchers could find a way to give them a “coma” (as indicated by neuronal activity), perhaps by simulating brain injury, they could test different compounds to try to return that activity to a single code of consciousness.
Another route is through modeling the coma “in silico” – in the computer. Tucker recently drove an effort To train deep neural networks to detect consciousness across multiple brain regions, leading to realistic simulations of conscious brain states and disturbances of consciousness. This will allow him and his colleagues to test whether different types of deep brain stimulation can transform the brain’s unconscious simulation into a conscious state. They can then try these types of stimulation on coma patients.
“Now that we have a good model of the comatose brain, the awake brain, and artificial intelligence that can detect the difference, we can simulate the stimulation of each brain structure at the whole-brain level.”
Daniel Tucker
Saxa what?
Tucker is probably very excited about the potential cure derived from his treatment Recently published research. He trained the AI model on relevant data from scientific literature to predict whether a drug could “wake up” someone based on its 3D structure.
“AI has been really good at that,” he says. “It can pick up bioactive structures in molecules that we might not have thought about or looked at.”
But when the AI model finished its work and returned a list of potential pharmaceutical treatments, Tucker was stunned. The diabetes medication was significantly higher than all other medications.
“I’m sitting here at my laptop and the AI is making its most important predictions, and I’m like, ‘What is saxagliptin?’ He remembers.
Tucker tweaked the algorithm’s parameters over and over again, and consistently returned the same answer: saxagliptin. Maybe the AI was onto something.
He has found some preclinical work that shows the drug helps treat Parkinson’s disease and stroke. He then educated himself on how the medication worked. Saxagliptin inhibits DPP-4, the enzyme that breaks down GLP-1, a hormone now widely known because the new wave of weight-loss drugs like Wegovy and Moonjaro mimic it to promote satiety. However, DPP-4 also alters levels of a host of other brain-modifying compounds.
“What has become clear is that it appears to address all known pathophysiology of disorders of consciousness,” Tucker found.
So Tucker got this promising result, but he still didn’t know if it meant anything. Then he and his colleagues compared that to something more realistic. He examined the medical records of thousands of coma patients at UCLA, and it became clear that people who accidentally took saxagliptin or other similar drugs like Wijovi woke up from comas at much higher rates than coma patients who did not.
Scientists know of other drugs that can enhance arousal and awareness in comatose patients, but they are only minimally effective. Amantadinean antiviral also used for Parkinson’s disease, is the most commonly used. Tranquilizer Ambien It can also be strangely effective. In rare cases, comatose patients regain consciousness when the drug takes effect, but then lose consciousness when it wears off.
Tucker says saxagliptin could be an even more promising new pharmaceutical tool.
“What’s exciting about this class of drugs is that they work through a completely different set of pathways that are different from anything else we’ve looked at in terms of disorders of consciousness and coma.”
A promising treatment experience
Over a video call, Tucker was excited about the prospect of testing saxagliptin in a clinical trial in comatose patients.
“People want their loved ones back. Especially in these chronic conditions, it’s very difficult, because they’re there. They’re alive. They’re breathing. They’ll sleep. They’re waking up. But they’re not responding to anything.”
But what sharply dampens his enthusiasm is the bleak state of funding for research into disorders of consciousness.
“This is not something that drug companies really care about,” he says. Federal grants for this type of speculative research are also difficult to obtain, especially for early-career scientists. The cost of the ideal trial he envisions would easily exceed six figures. He would like to have at least 30 comatose patients participate, so as not to miss a rare but meaningful effect: someone might regain consciousness.
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