In July 2005, Carol was hit by two cars while crossing a busy road. She survived, but suffered a massive brain injury, which left her in a vegetative state with little hope of meaningful recovery. Carol’s life would never be the same again. Two cars and a moment’s distraction had redefined the rest of her existence; a shocking reminder of how vulnerable we are, and how the trajectory of our lives can change in an instant.
The vegetative state is often described as ‘wakefulness without awareness’. These patients open their eyes and will often have sleeping and waking cycles, although they remain non-responsive to any form of external prompting or stimulation. They are both ‘there’ and ‘not there’, lingering in the indeterminate space between life and death. For decades, it was assumed that such patients lack any awareness, including who they are, where they are, and the predicament they are in.
Several months after her accident, we put Carol into a fMRI scanner at Addenbrooke’s Hospital, Cambridge, and asked her to imagine waving her arms in the air, as if she was playing a vigorous game of tennis. Amazingly, a part of her brain known as the premotor cortex ‘lit up’ in exactly the same way as it does in healthy people, when asked to imagine the same series of actions in the scanner.
This startling result told us that Carol must have understood the instructions and, furthermore, she had been able to turn them into a response; not a physical response, like squeezing a hand or blinking an eye, but a conscious brain response that confirmed beyond doubt that Carol was not vegetative at all, but conscious and aware, even though she had been physically non-responsive for more than five months.
After a few more years of scientific tinkering, we took the technique one stage further and successfully communicated with a young man called Scott who had been apparently vegetative for 12 years following a near-fatal collision with a police car.
By changing his pattern of brain activity in the scanner to indicate a ‘yes’ or a ‘no’, Scott was able to tell us that he knew where he was, how long he’d been there, what he enjoyed watching on TV, and whether or not he was in any pain (he wasn’t). Nevertheless, at the bedside, Scott remained non-responsive whenever he was examined by his doctors and care staff.
By 2016, more than 1,000 patients around the world had been scanned using variations on the brain-imaging technique we had developed, and an independent scientific review concluded that between 20 and 25 per cent of them were like Carol and Scott; conscious and aware, despite their outward appearance, trapped in their immobile bodies, listening silently to every conversation at their bedside, and every decision that had ever been made on their behalf.
While no one knows exactly how many vegetative-state patients there are in the world (in the United States, it has been estimated that there are between 15,000 and 40,000), these figures confirm that tens of thousands of them may not be what they appear to be at all.
Despite this astonishing series of discoveries, the various regulatory bodies that determine whether the findings will be used to benefit the lives of all patients with ‘disorders of consciousness’, like the vegetative state, continue to drag their feet. In 2021, the Royal College of Physicians revised the UK guidelines on the management of these patients, stating that “once a patient is in a prolonged disorder of consciousness… repeat imaging is not routinely required”.
For too many years, patients who are diagnosed as being in a vegetative state have been warehoused – an unfortunate term that is frequently used to describe how they are often ‘written off’, denied the expertise of professionals who can carefully assess their mental functioning over time and spot subtle signs of emerging awareness. Yet we now know that many of these patients have been completely conscious all along. This thought still makes me immensely uncomfortable.
To fail to test for consciousness using technologies like fMRI is to deprive tens of thousands of brain-injured patients worldwide of an important benefit: the opportunity to make themselves heard, to communicate with their clinical team and their relatives, and to contribute to decisions about life-preserving treatment, rehabilitation and other interventions.
By failing to make these scans available, we abandon them. They are voiceless, yet we have created technologies that can give them a voice. It is high time we allow them access to these technologies so they might once again take their place among us in the land of the living.
- This article first appeared in issue 370 ofBBC Science Focus Magazine – find out how to subscribe here
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