Terry Wallis had been unable to respond to the world since 1984, when the truck he was riding in veered off an Arkansas bridge and crashed, tires up, into the creek bed below. Wallis spent two weeks in a coma, a state of prolonged unconsciousness, then lived most of the next 19 years in a minimally conscious state in which he could not communicate with words or gestures. But in 2003, at the age of 39, Wallis surprised both doctors and his family with his first word—"Mom"—followed by many others. Studies later found that Wallis' brain had continued to repair itself. Tests done 18 months after he emerged showed that Wallis had regained some motor function, strength, and fluency of speech, while brain scans showed more connectivity in damaged parts of the brain.
While many considered Wallis' recovery a miracle, those 19 years in between produced an interminable stretch of questions without good answers. For one, what was Wallis aware of when he appeared not to be responding? Even today, a coma diagnosis is accompanied by uncertainty, says Jose Suarez, a professor of neurology at the Johns Hopkins School of Medicine and director of the Division of Neurosciences Critical Care. "Families want to know: Is he or she going to wake up?" he says. And, if their loved one does wake up, what will their life look like?
Here's what we do know: A coma can be caused by traumatic brain injury (TBI), stroke, cardiac event, and complications from other illnesses, including COVID-19. Comas can also be induced intentionally to give the brain time to heal until swelling and pressure—which can cut off blood flow to the brain—can recede. But the balance between when a coma is helping the body and when the person is tipping toward decline is unclear. And even though patients in a coma can be kept alive for years, very little is known about what's going on under the surface.
All of this uncertainty can lead to a nihilistic attitude toward coma that's prevented us from learning more about the condition, Suarez says. "People immediately assume that just because you're in a coma, you're not going to do well, and therefore we should probably de-escalate care." But by withdrawing care, health care providers don't learn whether people will continue to survive or improve. "We're essentially cutting off the natural history of the disease."
But what if coma were considered, like diseases, something that could be treated? Launched in 2019 by the Neurocritical Care Society, the Curing Coma Campaigne is the first to address coma as a treatable medical issue, bringing together researchers from Johns Hopkins and around the globe to better understand the condition and improve outcomes for those like Wallis, who died this spring at 57. The campaign has hosted two conferences and an annual World Coma Day, with members publishing original research on the topic. Beth Slomine, co-director of the Center for Brain Injury Recovery at the Kennedy Krieger Institute, says that the campaign aims to convey that individuals who have experienced coma can indeed recover, while its researchers work to develop new strategies for diagnosis and treatment.
In particular, the Curing Coma effort wants to explore how biomarkers, such as molecular and cellular markers shown under brain scans, can indicate neurological health. These tools help health care providers make earlier diagnoses and understand both the current level of a person's consciousness and how they might be responding to interventions, such as medications or noninvasive brain stimulations, two approaches that are under study.
For Suarez, the true challenge underlying coma research is understanding consciousness itself. Consciousness has been explored by scientists, philosophers, and artists for hundreds—if not thousands—of years and may have an even bigger question beneath it: What does it mean to be human? While this question may always be with us, the Curing Coma Campaign aims to help coma patients and their families find the answers that are within reach.