Life / Health

Beyond sci-fi: A neuroscience expert's journey into the Gray Zone

University of Western Ontario professor helps break through to patients who may seem vegetative, but are aware — and want to be heard.

Over the past 20 years, neuroscientists have discovered how to peer into the brains of unresponsive patients using new technologies such as functional MRI, PET scanning and electroencephalogram (EEG).

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Over the past 20 years, neuroscientists have discovered how to peer into the brains of unresponsive patients using new technologies such as functional MRI, PET scanning and electroencephalogram (EEG).

Meet Kate. She was a 26-year-old preschool teacher, happily living life with her partner and cat in in Cambridge, U.K.

Then she came down with a cold virus that spread to her brain and spinal cord. Once she was out of danger, there was no option to pull the plug: her heart was beating. She could breathe on her own. But the virus had decimated the parts of her brain responsible for speech and conscious movement. She was awake, but apparently not aware. Diagnosis: persistent vegetative state.

But Kate’s inner life was nothing like a vegetable. She was one of the 20 per cent of totally unresponsive patients who, thanks to new brain-imaging technology, can communicate, in a limited way, with the outside world.

They can even answer yes-or-no questions with their minds, such as by imagining playing tennis. Rarer still, Kate recovered communication ability after years locked inside her own body.

She was in what University of Western Ontario neuroscience professor Dr. Adrian Owen calls the Gray Zone, which is the subject of his new book, Into the Gray Zone. He spoke to Metro about the “one in five,” and what their stories can tell us.

From a layperson’s perspective, brain-imaging technology seems like magic: Abracadabra, the brain lights up and we can tell they’re thinking about tennis. What can these machines do? What can’t they do?

We’d like to be able to say to (vegetative patients), “If you can understand me, raise your left hand.” But they can’t do that. So we go straight to their brain and say, “If you can hear me, please activate this part of the brain.” And asking somebody to imagine a certain task is a way of doing that. We’re not reading minds. But we are able to generate simple imagery responses to a yes or a no.

You write about how patients’ loved ones, desperate to see signs of life, often misinterpret random movements as, for instance, the person squeezing their hand. How do you know the brain activity you’re seeing isn’t random?

We would not take a single brain imaging response as being evidence at all. We typically try and replicate it 10 times. We put the bar very high. In all of the cases I’ve described in the book, there is no possibility – I can say that with my absolute best neuroscience hat on – that these are chance occurrences.

Why do some people end up in the “one in five” who you connect with, and others don’t?

It’s very perplexing, even for neuroscientists. There’s an area of the brain called the thalamus, it's a bit like the relay station for the whole brain. It has a connection to the motor cortex, and that’s the area that allows you to move. And if you have damage to that connection, you can think of an action, but you can’t actually carry it out. In general, the patients who produce the best responses in the scanner are the most likely to make a recovery.

People who previously couldn’t communicate can now say if they’re in pain. Has this evolved your view on the debates about end-of-life and suffering?

For me personally, it’s the realization that what you see is not necessarily what’s actually going on there. Whether someone has Alzheimer’s disease or Parkinson’s or brain injury, we should never presume what it must be like to be that person, because science may tell us something very different.

What are the next steps for this research?

We’re stuck in this “now what?” situation when we initiate communication (with vegetative patients). We, and others, are exploring means by which they could communicate in a routine way with their families. One of them is a type of EEG; another one is called near-infrared spectroscopy. It’s much more cost-effective and portable, but it does just about as well as fMRI.

Why do you devote so much of your book to patients’ families and their role?

Brain injuries affect us all. Very often the focus is on the patient in scientific writing. The reality is very different. Families take on extremely time-consuming and economically expensive rehabilitation efforts. People who don’t know somebody with a head injury often think that so-and-so had an accident, and they’re not the same as they used to be. The truth is, so-and-so had an accident, and nobody who knows them is the same as they used to be.

(Families) spend hour after hour, day after day with patients. They really know every nuance of the patient’s behaviour in a way that the best neurologist in the world couldn’t possibly. A doctor also can’t look for signs of the person they knew because they never knew the person before (brain damage). That does make a huge difference.

You include so many personal stories. Which one touched your heart the most? 

I think the story of Jeff, out in Edmonton. His father had taken him to the movies every week for, I think, 14 years. He had no idea if his son was in there or not. We showed Jeff an Alfred Hitchcock movie while he was in the MRI scanner. It was immensely satisfying to be able to go to the father and say, “We showed him a movie. And you’re right. He is watching the movies. He is understanding. And all those trips to the theatre have given him a huge amount of pleasure.” 

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