Neuroscience: the mind reader
June 14, 2012 | Source: Nature News
Adrian Owen (credit: Adrian Owen)
Adrian Owen has found a way to use brain scans to communicate with people previously written off as unreachable in a so-called “vegetative state.” Now he’s fighting to take his methods to the clinic.
Patients in these states are usually written off as lost.
Owen took fMRI scans of a 23-year-old woman in a vegetative state while he asked her to imagine playing tennis and walking through the rooms of her house. When healthy, conscious adults imagine playing tennis, they consistently show activation in a region of the motor cortex called the supplementary motor area, and when they think about navigating through a house, they generate activity in the parahippocampal gyrus, right in the centre of the brain.
The woman, who had been unresponsive for five months after a traffic accident, had strikingly similar brain activation patterns to healthy volunteers who were imagining these activities, proving, in Owen’s mind, that she was conscious.
Other researchers contended that the response was not a sign of consciousness, but something involuntary, like a knee-jerk reflex. Daniel Greenberg, a psychologist at the University of California, Los Angeles, suggested in a letter to Science that “the brain activity was unconsciously triggered by the last word of the instructions, which always referred to the item to be imagined”.
But Owen went on to bolster his case. Working with neurologist and neuroscientist Steven Laureys from the University of Liège, Owen showed that of 54 patients in a vegetative or minimally conscious state, five responded in the same way as the first woman. Four of them were in a vegetative state. After refining their methods, the researchers asked patient 23 to use that capability to answer yes-or-no questions: imagine playing tennis for yes, navigating the house for no. They then asked about things that the technicians scoring the brain scans couldn’t possibly know.
But Parashkev Nachev, a clinical neuroscientist at Imperial College London, criticizes the work for “assuming that consciousness is a binary phenomenon”. Many patients, such as those having certain types of epileptic seizures, exhibit limited responsiveness without being conscious. Nachev says that more data are needed to indicate where in the continuum of cognitive abilities people in vegetative states fall.
Currently, there are tens of thousands of people in a vegetative state in the United States alone. Owen reckons that up to 20% of them are capable of communicating; they just don’t have a way to do so. “What we’re seeing here is a population of totally locked-in patients,” Owen says.
Owen now wants to put his technique into the hands of clinicians and family members.
An early goal of the program was to repeat the fMRI findings using an electroencephalogram (EEG). An EEG lacks fMRI’s precision. But other tasks — imagining wiggling a finger or toe — produce signals that, through repetition, become clear. An EEG is also cheap, relatively portable and fast (with milliseconds of lag compared with 8 seconds for fMRI), meaning that the research team can ask up to 200 questions in 30 minutes. Now, using an EEG, Owen is planning to study 25 people in a vegetative state every year.
One goal is to identify other brain systems, such as smell or taste, that might be intact and usable for communication.
Owen’s methods raise more difficult dilemmas. One is whether they should influence a family’s or clinician’s decision to end a life. If a patient answers questions and demonstrates some form of consciousness, he or she moves from the “possibly allowed to die” category to the “not generally allowed to die” category, says Owens.
Even more ethically fraught is whether the question should be put to the patients themselves. Owen hopes one day to ask patients that most difficult of questions, but says that new ethical and legal frameworks will be needed. And it will be many years, he says, “before one could be sure that the patient retained the necessary cognitive and emotional capacity to make such a complex decision.”
So far, he has stayed away from the issue. “It might be a little reassuring if the answer was ‘no’ but you can’t presuppose that.” A “yes” would be upsetting, confusing and controversial.
Ref.: Martin M. Monti et al., Willful Modulation of Brain Activity in Disorders of Consciousness, New England Journal of Medicine, 2010, DOI: 10.1056/NEJMoa0905370
Comments (11)
by Vern Westgate
I have a semi-related question. Persons with ALS (Lou Gherig’s disease), who choose to go on ventilators when their breathing fails, still have brain function. But many loss all other functions by which to communicate. Would this technology give them the ability to communicate, as it were, telepathically?
by Christian Gehman
Try reading the patients fiction and poetry, see if those sympathetic areas light up in response to a story. If there’s any thought going on, the story could be about someone who opened a red door (lion) or a blue door (meadow with cows). The red door could be labeled Yes, the blue door no. If the brain scans show different function for red and blue door, this might indicate that communication is possible.
by Jack
Frustrating (and terrifying too) for a vegetative person to consciously hear someone else declaring him/her unscious.
Wonderful experiment though.
by Dennis R.
Terri Schiavo might have confirmed what her husband said– that she didn’t want to live in a vegetative state.
Being able to infer consciousness of and communication with someone by measuring their brain waves seems ground-breaking. But will their brain functions improve, stay the same, or decline with continued stimulation? It’s an area for further study, granted. But consider that Owen says he believes only 20% of people in what has been called a vegetative state are capable of communicating. What does he base this belief on?
To my way of thinking, brain activity in someone who can’t speak, eat, move, or communicate without external aid still seems akin to a vegetative state. At what point do the recipients of such treatment get to decide that too? When and how often will they be asked if they want their lives to end? Will they have the right to make such a choice? Can we trust the interpreters of their brain activity to give honest answers? Who gets to play god in such situations? Our lawmakers? Is questions of ethics, whose ethics will “rule?”
by Sno
I totally agree with the idea that consciousness isn’t a binary thing. You really just need to look around you to know that.
by Marcos Marin
Why those geniuses don’t simply ask the subject NOT TO imagine playing tennis?! This would completely destroy the other genius’ psychologist argument… they should consult with the nlp crowd, if with smarts like this they can already ask simple yes/no questions, richard blander would make them sing! hahaha
by qwerty_jones
If that technology had been around a couple of years ago they could have asked Terri Schiavo what she thought as they starved her to death.
The criticism seems to be coming from the utilitarian camp who are eager to switch off as many patients as possible, as quickly as possible.
With the Singularity being a distinct possibility within our lifetimes, this utilitarian stance is no longer valid or acceptable.
by St. Abyssal
Terri Schiavo’s brain had atrophied to the size of a walnut. She was already dead before they “starved” her.
by Editor
Source?
by qwerty_jones
Actually Terri Schiavo’s brain atrophied to half the size of what it should have been, but still far larger than a walnut.
http://en.wikipedia.org/wiki/Terri_Schiavo_case
One could potentially live with that. Medical history is full of miracles. When I was a medical student I remember a professor telling in a lecture that there once was a dancer without a cerebellum, although I cannot find a source now. (A cerebellum is responsible for controlling movement.) In any case sometimes people recover from most grave injuries. Although usually and sadly they don’t.
In Terri Schiavo’s case the autopsy later showed that apparently all pyramidal neurons were gone.
It is possible she would not have been able to communicate at all. Or conversely she might have confirmed that she agrees with her husband. My point is, had this technology been available then millions of dollars may not have been spent on litigation. And much anguish could have been spared to her parents and other parties involved.
by Bri
When we are asleep, the brain is still processing information. That’s how you can react to a loud noise. When you see someone in rem sleep, try talking gently to them. I used to get a kick out of doing that in my high school years. The person sleeping will often babble incoherently. When they wake they don’t remember a thing! The brains awake, but they’re not home.