Opinion | New Findings About Consciousness Are Changing How I Think About Patients

The fourth floor of the long-term-care hospital where I sometimes work houses patients with severe brain injuries. When I am called there to consult, I always hesitate before entering the room. Of all the ways that our bodies can fail, brain injuries are some of the most devastating to witness. Some patients moan involuntarily. Others lie still, their eyes open but unresponsive.

As I place my stethoscope on the patient’s chest, often without a word, I reassure myself that at least the patient is unaware. Her personhood is gone. She is “not in there” any longer.

But an increasing body of research indicates that patients who have suffered catastrophic brain injuries experience a far more complicated reality. A provocative large study published last year in The New England Journal of Medicine suggests that at least one in four people who appear unresponsive actually are conscious enough to understand language. As a doctor who sometimes sees patients like this, these findings are, in a word, terrifying.

Studies like this raise the possibility that there are tens of thousands of men and women locked inside their own minds, isolated to a degree I cannot even imagine. They are voiceless and largely invisible, with some of them being cared for in nursing facilities.

There are a handful of researchers in a few institutions working to identify these patients and develop tools they can use to communicate. A lack of resources is one major barrier. A larger one is philosophical. The way many doctors think about these patients reflects the medical system’s inability to deal with uncertainty, and even what kind of life we believe to be worth living.

I’ve often struggled with how to recommend care for patients with uncertain recoveries after brain injuries. As an intensive care unit doctor, I see patients in the early days following a catastrophic event, collecting as much information as possible to guide families’ decisions about whether to continue life-prolonging therapy or shift to providing comfort. These conversations are challenging, particularly when our neurologist colleagues say the patient just needs more time. I worry that continuing aggressive interventions, like the surgical insertion of a tracheostomy tube, might cause patients and their families needless suffering while chasing an outcome that might be unattainable. At the same time, I never want to withdraw life-prolonging support too early.

When I see these patients again at the long-term-care hospital months later, still unable to communicate with the outside world, I find myself asking: What is worse — to offer hope even if it does not come to pass? Or to deprive someone of the chance to surprise us?

These questions are why I read the recent New England Journal of Medicine study with such interest. Neurologists queried nearly 250 unresponsive patients while monitoring them with brain imaging or brain-wave monitoring. The patients were asked to imagine themselves doing activities, such as playing tennis or swimming — complex cognitive tasks that require sustained attention. One would assume that people who appear completely unaware of the outside world, unable even to squeeze hands when asked, would not be able to understand or follow such a request.

And yet the brain imaging suggested that one-quarter of the patients heard the instructions and followed them — a sign that they are exhibiting what some neurologists might call “covert consciousness.” Given the difficulty of the test itself, the researchers believe the one-fourth figure is actually an underestimate of how many patients were experiencing some level of consciousness.

These patients were tested a median of eight months after their brain injuries. In other words, many of them could have been living with covert consciousness for quite a while, aware enough to understand language but without any ability to express it. “How many people are lying in bed, getting ignored, and the staff are talking about them as if they’re not there, not putting books-on-tape or the TV on?” asked Brian Edlow, a critical care neurologist at the Massachusetts General Hospital and a co-author of the New England Journal of Medicine study.

We do not know. Clearly there are patients for whom standard neurological exams cannot reveal their actual level of brain functioning. And yet there is no concerted, widespread effort to use higher-level testing to assess these patients for covert consciousness (despite recognition that these assessments can do so). The type of brain imaging and the subsequent data analysis require money, skilled expertise and personnel. This is not available at most institutions, and surely not at most chronic care facilities.

There is also the issue of what Dr. Nicholas Schiff, a neurologist at Weill Cornell Medicine and a co-author of the New England Journal of Medicine study, described as “futility” bias, the belief that even if we knew what these patients were going through, there is still no way to really help them.

This is no longer true. For patients who are truly locked in (meaning their cognitive abilities are completely preserved but they are unable to move because of a specific stroke or a neuromuscular disease, such as amyotrophic lateral sclerosis, or A.L.S.), researchers are testing what is called an intracortical brain-computer interface. This machine is implanted in the brain, reads the input from the patient’s motor cortex — essentially translating what his body is trying to say — and turns it into language. This technology has given people who are completely paralyzed the ability to communicate.

Communication with this technology hasn’t been attempted for people who have covert consciousness. Since these are patients who have had brain injuries, any communication would likely be imperfect. But we will not know how much is possible until we try, which is why Dr. Schiff and his team are working on research protocols that could one day offer these patients a voice.

I recently found myself at another bedside in the long-term hospital, visiting a young man who had suffered a severe brain injury from a bicycling accident nearly six months before. His parents sat at his bedside, as they had every day. The patient’s eyes were open, but he did not respond to my voice, nor did he squeeze my hands when I asked, or follow me with his eyes as I walked through the room. I did not know how much of him was still there, and, if he was aware of any of this, whether it would be a life he would find acceptable.

This time, with the recent research in mind, I paused. I spoke to him before I began my exam. Maybe it didn’t make a difference, but maybe it did. As profoundly troubling as these questions are, as uncomfortable as it is to engage with this level of uncertainty, we can’t look away.

Daniela J. Lamas, a contributing Opinion writer, is a pulmonary and critical care physician at Brigham and Women’s Hospital in Boston.

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