Consider what makes you the person you are: your memories, your personality, your ability to think and feel. Now imagine losing your ability to make contact with the outside world.
If others could no longer tell whether you were aware of yourself and your surroundings, would you still be you?
Dr. Adrian Owen has devoted his research to reaching out to patients with serious brain damage who exist in a murky state of consciousness. He has been asked to test the consciousness of individuals such as Toronto patient Hassan Rasouli, whose case sparked a historic Supreme Court ruling on determining whether to withdraw life support; Oakville resident Juan Torres, whose astounding recovery from brain damage defied doctors' expectations; and even the late Israeli prime minister Ariel Sharon, who was incapacitated in his final years following a stroke.
As Owen explains in his new book, Into The Gray Zone: A Neuroscientist Explores the Border Between Life and Death, an estimated 20 per cent of patients whom doctors typically regard as vegetative or non-responsive are more aware than they seem. They can see, hear and understand what's going on around them, but are unable to communicate with the outside world.
If they could, what would they say? Owen, who is a Canadian Excellence Research Chair in cognitive neuroscience and imaging based at the University of Western Ontario's Brain and Mind Institute, has been trying to find out.
Twenty years ago, the British neuroscientist was stunned to discover that the brain scans of a patient, who was presumed in a vegetative state, showed her brain responded to photos of familiar faces.
The discovery led him to develop techniques – using brain-scanning technology – to determine whether patients are conscious, and eventually to communicate with some of them who are.
Owen has encountered his share of skepticism, including from colleagues who have questioned his findings. As Owen mentions in the book, the director of the Applied Psychology Unit of the Medical Research Council at Cambridge, where he was previously based, was less optimistic of the results of an early experiment that indicated brain response from a vegetative-state patient, telling him: "It could just be an automatic response."
Other scientists wrote an article in the Lancet in 2013, expressing their concerns about the validity of one of his team's studies, which used electroencephalography (EEG) to detect awareness in patients.
Owen says this kind of scrutiny is all part of the scientific process.
"When you publish a new technique in neuroscience – especially one that involves complex mathematics and computing – it is inevitable that some people will either not completely understand the methods, or think that they have a better way of doing the same thing," he says.
If he can bring his research into clinical practice, his findings could have significant implications for the diagnosis and care of severely brain-damaged patients. Yet, in an interview with the Globe, Owen explains he and his fellow researchers still have a long way to go to fully understanding the grey zone and they're still refining the technology for communicating with those trapped there. But for those with whom he has made contact, having others know they're aware has given them back their sense of "personhood," he says.
What is the difference between being in a vegetative state, being in a coma and being locked-in?
A person in a coma really looks like they're asleep. They have closed eyes, they don't have sleeping and waking cycles, and they very rarely move at all. That's typically the first thing that happens to you after you have a serious brain injury. A coma will rarely last more than a couple of weeks.
After that, some people emerge into a vegetative state, and this is a condition where, now, patients have their eyes open. They look around the room, though not at anything in particular. They'll have sleeping and waking cycles. They'll do spontaneous things such as grunt and snore when they're asleep. And you can exist in that stage for decades. They never respond to any form of external stimulation, which is true of both coma and vegetative state. And that's the basis upon which we've always believed these patients aren't aware.
Locked-in syndrome is less often confused with the other two. It's a situation where a patient is cognitively fine, but they've physically lost all movement to their body or typically they can just retain eye movement or eyebrow movement. Famously, some patients have been able to use that to communicate with the outside world.
So what does it mean to be in the 'grey zone'?
Some patients who appear to be in a vegetative state – and by that I mean using every clinical tool our best neurologists have available to them, they will make no responses – are actually mentally conscious. They can hear, they can see, but are nevertheless not able to make any responses to the outside world. In a functional sense, they are "locked in" inside their heads, but they don't have locked-in syndrome.
The reason I use the term "grey zone" is there is no clinical name. We have no title we can give these patients. This is a population of patients who have always existed, but we only discovered them in 2006.
You predict 20 per cent of unresponsive patients are in this grey zone. What can you say about the other 80 per cent?
There are two ways of answering that question. One of them is just drawing on parsimony and saying, as far as we know, they are what they appear to be. That is, they are in a vegetative state. Their brain is just operating on autopilot. They breathe, they swallow, they blink, but they have no awareness of who they are.
The other answer I can give you is that perhaps some of them are not in that situation. Until 10 years ago, we thought 100 per cent of vegetative patients were exactly as I described, completely unaware. And now we know that's not true for at least 20 per cent. Scientifically, there are very good reasons that number could go higher.
I don't for a minute want to suggest all patients are aware or all patients are conscious; the effects of very severe brain damage are devastating. But it's certainly possible some of them have a level of awareness that we don't yet understand.
With your first patient, Kate, you discovered she was able to recognize photos of familiar faces. How did seeing her brain activity in the scanner affect her quality of life?
It was 20 years ago this year that we scanned Kate. At the time, people thought we were absolutely bonkers for putting patients like Kate in scanners because this is very expensive technology. People thought, there's no point. You're going to see no brain activity.
So it was an enormous surprise to find that when we showed her a picture of a face that was familiar to her, the part of the brain we know is involved in facial recognition lit up. This changed the way people thought about Kate, [who eventually regained the ability to speak] and people certainly started to treat her very differently immediately afterward. As she said to me many times since, "At that point, I went from being a body to being a person again."
At what point did you feel sure the brain signals you were picking up weren't just coincidental?
From the very beginning. By the time I put Kate in the scanner, I'd had almost 10 years of experience running brain-imaging studies. So this wasn't something we just stumbled upon. By then, I understood a lot about what would and what would not activate the brain.
It literally worked like this: I pointed at an area of the brain and said, "If she can recognize faces, that area of the brain is going to light up." And that is exactly what happened. It's just not the type of thing that happens by scientific chance. We then did it on a second patient, and it happened again. So you very quickly build up a level of confidence.
What I think we were less sure about was what exactly those signals meant. It was about 10 years before we could point to a patient like Kate and say, "That person is definitely conscious."
Can you explain how you were able to communicate with patients in the grey zone by asking them to imagine different scenarios?
If you were able to raise and lower your arm on demand, it wouldn't take me very long for me to decide you were conscious. You obviously understand the instructions you've been given, and you're generating an action based on those instructions. That's exactly what we were doing with patients, but the actions they were producing were brain actions versus bodily actions.
It's a huge scientific step, but a very small theoretical one to turn that into a method of communication, where we basically asked someone questions. We'd say, "If the answer is 'yes,' imagine playing tennis. If the answer is 'no,' imagine moving around your house."
In the very early studies, we would ask people questions we knew the answers to. So we'd say things like, "Is your name Adrian?" And if the tennis-playing area of the brain lit up, the area involved in motor imagery, we knew they were saying "yes," which meant not only were they communicating with us, they also know their name is Adrian. And then, we'd say, "Okay, is your name Paul?" In that case, the spatial navigation area of the brain would light up and then we would know they were saying "no."
This method is obviously restricted to "yes" or "no" questions, because they could only do these two things. But it very quickly became like the parlour game 20 Questions, and you can learn an awful lot about people. We moved onto things like, "Are you happy?" and "Are you in pain?" and in one case, "Do you want to continue living like this?"
In the book, you were apprehensive about asking whether a patient was in pain. How come?
Well, it terrified me, to be honest. It was the first time we'd really asked a question where I knew we could have an enormous impact on a patient's life. Until then, it had been questions to verify communication, like, "Do you know what year it is? Do you know where you are?" They were more practical nuts-and-bolts questions about how much the patient knew about who they were and their predicament.
For 12 years, [a patient named] Scott had been supposedly in a vegetative state at that point. The idea, for me, that he could have been in pain that entire time and we knew nothing about it, it's terrifying. I think that does start to touch on what many people think of as a fate worse than death.
Ultimately, in your own research, what do you hope to achieve?
One of the things most of these patients complain about, they don't tend to recover and say, "I really missed seeing my children grow up." They say, "I really missed the sense of control. Every single decision was made for me. Every single light switch that was turned on, every time I was fed, every time the TV channel was changed, that decision was made for me. I had no control of my life."
The goal I've really been pursing in 20 years is to try to return some autonomy and decision-making to patients wherever possible. I see family members making incredibly hard decisions about whether to, for example, withdraw life support in the neurointensive health unit. Given that we now know there are patients who we used to think were incapable of making those decisions, who may well be capable and may well want to make that decision, what I'm trying to do is develop technologies and use neuroscience to try wherever possible to give that voice back to these patients.
This interview has been condensed and edited.