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WHEN he found out that his old flame, Maureen, was in a vegetative state as a result of a brain haemorrhage, started wondering whether she, and other people in a similar situation, might have some awareness. He was already scanning parts of the brain to study their function, so when he got the chance a year later to scan Kate, a woman in a vegetative state, he jumped at it. Kate made occasional involuntary movements, but didn鈥檛 respond to external stimuli. It was 1997, and it had always been assumed that people in this condition had no conscious awareness at all. What Owen uncovered would change everything.

What made you scan someone in a non-responsive vegetative state?

This idea was bonkers at the time. But after what happened to Maureen, it was on my radar. It seemed logical that some people might be aware, because people with locked-in syndrome 鈥� in which people can move nothing but their eyes 鈥� are cognitively fine. It seemed probable that there would also be a group of people who are conscious but couldn鈥檛 even move their eyes. But there was a lot of resistance to the idea, because it makes us uncomfortable to think that a person might be completely conscious but trapped inside themselves. When my colleagues said it wasn鈥檛 possible, I鈥檇 say, 鈥淗ow would you know? You have no way of detecting it.鈥�

And did you find any activity in Kate鈥檚 brain?

A viral infection had left her in a vegetative state, but her brain was responding exactly as a healthy person鈥檚 brain would. We showed her photos of family members, for example, and the same part of her brain lit up on the fMRI scan as yours would if I did the same thing to you. That was the first indication we had that any of these people had any cognitive function.

How did you feel when you realised her brain was working?

In those days, the results were a bunch of numbers 鈥� but we looked at them and went, hang on a minute, these numbers suddenly all get really big. I think she鈥檚 activating! It was tremendously exciting.

Was Kate conscious?

No, we couldn鈥檛 say that. We thought wow, maybe she鈥檚 in there. And then somebody said, well is she? Face recognition is an automatic brain response, it鈥檚 not something you necessarily have to be conscious to do.

So you had to work out how to detect consciousness?

We tried speech on the next patient, and again their brain responded normally. But then we wondered, would an unconscious brain still perceive speech? We tried it on healthy people who had been sedated and it turns out that they do. We worked out that a lot of responses don鈥檛 necessarily indicate consciousness. It took us a decade to solve that problem.

And how did you solve it?

I realised I had to get a patient to somehow tell me they were conscious. If I wanted to know if you were conscious, I would say raise your arm, and you would raise it. And I realised that with fMRI we had a tool that could allow someone to do that with their brain.

So we asked someone to imagine playing tennis. It was a simple way of asking a person to do something that would make them think about moving their arms because we knew that imagining big, sweeping arm movements activates the brain鈥檚 premotor cortex. That was a pivotal moment.

What happened when you asked them to imagine playing tennis?

The premotor cortex lit up on the scan. Then we said stop, and the activity went away. It was incredible because this was a woman who had been hit by two cars while crossing the road, who had been in a vegetative state for five months and who had not produced a single response. That鈥檚 the point when I knew we had something really important. that anybody had proved a vegetative patient could actually be conscious.

So people whose brains respond are not in a vegetative state at all?

In a vegetative state, by definition, there is no awareness. The patients that we are uncovering are some other thing, for which there is no name, because nobody knew it existed before we found them.

Have you tried communicating with them?

At the start we were very conservative. If we had rushed in and said we could communicate with the woman who had been hit by cars and then failed to get it working, that would have been incredibly disappointing for her family.

鈥淚t鈥檚 uncomfortable to think that people could be trapped inside themselves鈥�

I get people all the time saying, why don鈥檛 you just bring patients in and let the families talk to them? And the reason is we鈥檙e still not at that stage. It still takes about 5 minutes per yes-or-no question, with imagining playing tennis for 鈥測es鈥� or moving around their house for 鈥渘o鈥�. And it involves highly skilled individuals making careful decisions about data. We have to be very careful that we don鈥檛 promise too much.

We and other teams are now developing more portable brain-computer interfaces. But to my knowledge, no one has yet used one to allow communication in a patient who appears to be vegetative.

Are people treated differently after they show signs of awareness?

Yes, that鈥檚 happened many times. Kate, my first patient, made a pretty good recovery in the end, and I saw her a few years later. She said something she hated was the fact that she had been treated as an object. Once people know there is more going on in someone鈥檚 mind, they become much more interactive, they start to treat them as a person. I basically treat everybody as though they are completely conscious, though it鈥檚 an odd thing because I鈥檓 obviously getting nothing back.

Did you ever scan Maureen?

No, but someone else did, in 2010. There was no brain activity. For me, it was comforting that she obviously wasn鈥檛 suffering. She wasn鈥檛 aware. She hadn鈥檛 been lying there for 20 years in pain. I was glad about that.

What proportion of people in a vegetative state ever get scanned for brain activity?

Virtually zero. People get a basic MRI scan to assess any structural brain damage, but scanning for brain function is not routine care. It is more widely used than before, but typically, people in a vegetative state live for decades at home or in a hospital and are not continually monitored. They have been quite neglected.

It is well over 10 years since we proved that demonstrating awareness has clinical utility. It can help us find which patients are going to go on to do better. That alone means it should be more widely adopted. From my experience, awareness seems reasonably common.

So there must be thousands of people out there who are conscious but nobody knows?

Yes, I鈥檓 quite certain of that.

This article appeared in print under the headline 鈥淔irst contact 鈥� with a trapped brain鈥�