Condition first discovered by Schulich Medicine neuroscientist named by scientific community
By Jeff Renaud, special to Schulich Medicine & Dentistry Communications
While it has been 18 years since Adrian Owen discovered consciousness in patients in a vegetative state, hardly a day has gone by when Western University’s world-renowned neuroscientist doesn’t connect back to his Eureka moment.
And now, in a new study published Aug. 15 by The New England Journal of Medicine (NEJM), the medical phenomenon officially gets a name: ‘cognitive motor dissociation.’ The paper is co-authored by Owen and more than 50 leading authorities, including neurologists, doctors, imaging experts and research scientists.
The acknowledgement of cognitive motor dissociation – labelled colloquially as ‘covert consciousness’ by the Curing Coma Campaign – and its formal classification have been a long-time coming for Owen. When the discovery was first made public, some major luminaries in the field disavowed it, with some even calling it a one-off or a fluke.
“I have always believed in what we accomplished, but of course, it is rewarding to finally see it recognized in this way,” said Owen, a professor at the Schulich School of Medicine & Dentistry. “It was completely serendipitous that we just had the right patient at the right time. If she hadn’t been aware, then maybe we wouldn’t have kept going. But this particular woman’s brain activated in response to our new imaging test the very first time we tried it. And then, the story just exploded.”
On the origin of discovery
At the time, Owen, already a highly respected researcher at the University of Cambridge’s Cognition and Brain Sciences Unit, designed the ‘tennis task,’ which asks a patient to imagine playing tennis (a simple direction one could choose to follow or ignore) and something else like imagining walking around their house, or another activity not related to volatile arm movement. Both directions require a cognitive decision to be made, but importantly, light up two unique parts of the brain during a functional magnetic resonance imaging (fMRI) scan and thereby, as Owen described, indicate the patient is conscious.
The findings from Owen’s landmark study were published by Science in 2006.
“We first started to see brain activity in some vegetative patients about 10 years prior, but we just had no idea what it meant,” said Owen. “We showed them pictures and played them tapes of people speaking and bits of their brain would light up, but we couldn’t get beyond, ’Well, that’s very interesting. But are they conscious?’ And then I just had this Eureka moment where I realized what we needed to do was to get somebody to do something that can’t be an automatic reflex. It can’t be just an unconscious brain response. It had to be something that they do willfully and so we came up with the tennis task.”
In the new NEJM study, Owen and collaborators from six leading cognition and brain institutions from around the world, including U.S., U.K., Belgium and France, released data on a large group of seriously brain injured patients who had been tested using the tennis task. All told, 353 patients were assessed for the new study and approximately 25 per cent are indeed conscious.
Owen shared similar results 14 years ago in another NEJM study, in which he detected consciousness in one in four patients in a vegetative state, but only 50 patients had been tested at that time.
“Again, we always knew we were reaching these patients, but science takes time and as scientists we form a hypothesis, test the hypothesis by performing a study, publish the results and then retest it. And then others retest it. We’ve been retesting consciousness in patients in a vegetative state for 18 years,” said Owen. “And now, finally, it has a name: cognitive motor dissociation.”
-Professor Adrian Owen, Schulich School of Medicine & Dentistry
Research advances at Western
The same year as his first NEJM study, Owen was awarded a $10 million Canada Excellence Research Chair (CERC) in cognitive neuroscience and imaging at Western. Owen moved, along with most of his research team, to Canada in 2011.
After arriving on campus, Owen’s first Western study showed similar results using electroencephalogram (EEG) technology, a method which allows for more accessible bedside visits with patients as opposed to more cost-prohibitive and often impractical fMRI scans. The results were published in The Lancet in 2011.
For the new NEJM study, data from fMRI only or EEG only were available for 65 per cent of the participants, and data from both fMRI and EEG were available for the other 35 per cent. The researchers detected cognitive motor dissociation in 60 of the 241 participants (25 per cent), who had shown absolutely no behavioural responses when tested clinically.
Overall, cognitive motor dissociation was found most often in younger patients who suffered from head trauma while the best results for time between brain injury and assessment came for those tested less than eight months after the event.
Andrea Soddu, a Western medical physics professor and long-time Owen collaborator, is another pivotal figure in the efforts to unravel the complexities of cognitive motor dissociation.
“The challenge in cognitive motor dissociation lies in detecting brain activity that doesn’t translate into physical responses,” said Soddu, a co-author on the new NEJM study. “This disconnect between cognition and motor output often leads to false positives and negatives.”
Soddu’s future work will focus on leveraging AI-driven techniques with resting-state fMRI, EEG, and heart rate variability (HRV) data to refine these detections and deepen understanding of consciousness in patients with severe brain injuries, ensuring more accurate diagnoses and better patient outcomes.
Making contact
After nearly two decades of assessing patients, Owen is more confident than ever that what his team is doing brings relief to family members or friends regardless of whether the news they deliver is positive or negative.
“One could imagine, it’s worse finding out that your loved one is locked-in than finding out that they have no sense of who they are and where they are and the predicament that they’re in. But, this isn’t generally the case, and it’s completely the other way around,” said Owen. “They are almost always more satisfied knowing that the person they’d lost is still in there even though they can’t communicate with them as they once were able to do.”
Beyond gratitude and appreciation from his patients’ families and friends, Owen’s accomplishments have not gone unrecognized. In the 2019 New Year Honours List, Owen was made an Officer of the Most Excellent Order of the British Empire (OBE) for services to scientific research and earlier this year he was elected a Fellow of the Royal Society, joining the ranks of Charles Darwin, Albert Einstein and Stephen Hawking.
“This one discovery has 100 per cent completely changed my life,” said Owen. “Before the Science paper, my life at Cambridge was perfectly fine, but basically unassuming. I was just going about my days doing my work, but the discovery led to an entirely new field of research into the causes and consequences of serious brain injury that has shaped my career ever since. It resulted in my CERC at Western, moving to Canada and meeting my wife. Both personally and academically, the discovery has completely changed my life.”
