Vegetative state patients may soon be able to communicate

Sep 22, 2010 by Lin Edwards report
Communication in the vegetative state (Owen et al., Science, 2006; Monti et al., NEJM, 2010)

(PhysOrg.com) -- Researchers from Cambridge University in the UK have been able to communicate with brain-injured patients in "locked states" commonly referred to as persistent vegetative states (PVS). They predict such patients will soon be able to communicate and perhaps even move themselves around in motorized wheelchairs.

Neuroscientist Dr. Adrian Owen and colleagues used electroencephalography () monitors connected to 128 electrodes in a cap placed on the heads of brain injured patients, and were able to understand responses from them. Own thinks a similar system connected to a computer will be able to decode messages from their brains and allow them to communicate via a voice synthesizer and even control a motorized wheelchair. These systems could be available within a decade.

Dr. Owen used (fMRI) brain scans to prove that one PVS victim could understand queries and give “yes” or “no” answers to simple questions. The 29-year-old male patient had suffered in a car accident in 2003, and had been in a coma for two years before entering a persistent vegetative state. He appeared to be awake and blinked occasionally, but otherwise showed no signs of awareness.

The team used the fMRI scanner to measure the patient’s brain response while asking him questions. Brain signals associated with “yes” and “no” are complex and quite similar, and to overcome this problem the researchers asked the patient to imagine playing tennis for “yes” and walking through his home for “no”. Tennis movements activate regions at the top of the brain associated with spatial activities, while moving around the home is a navigational task that activates areas in the base of the brain. Using this technique the patient was able to correctly answer six test questions.

The team has now shown that similar responses could be achieved using EEG monitors, which measure in the brain. EEG has the advantages of being much cheaper, smaller, and more portable than fMRI, which uses magnetic fields and radio waves to detect electrical pulses in the . EEG also gives results much more quickly than fMRI, making a conversation possible.

Dr. Owen said “we have seen something that is quite extraordinary” and that we now have a moral and ethical obligation to find ways to help patients in persistent vegetative states to communicate. The communication will be via yes/no questions, but he said “you can get a long way with yes/no questions.”

The research findings suggest about 20 percent of PVS sufferers could be able to communicate, and this may raise questions about switching off life support systems for such patients.

Dr. Owen and several members of team will soon be transferring to research posts at the University of Western Ontario in Canada, where they will receive a grant worth around 20 million US dollars to continue the research.

Explore further: Flashes of light help researchers to both 'read' and 'write' brain signals

More information: -- Monti MM, Vanhaudenhuyse A, Coleman MR, Boly M, Pickard JD, Tshibanda L, Owen AM, Laureys S (2010), “Willful modulation of brain activity in disorders of consciousness.” N Engl J Med 362(7):579-89
-- Owen AM, Coleman MR, Davis MH, Boly M, Laureys S, Pickard JD (2006), “Detecting awareness in the vegetative state” Science 313:1402

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NameIsNotNick
5 / 5 (6) Sep 22, 2010
this may raise questions about switching off life support systems for such patients.


Absolutely, they can ask the patient!
moj85
5 / 5 (4) Sep 22, 2010
this. is. amazing. It doesn't seem like it would be too hard to extend the ability of this system to recognize more difficult concepts. 128 points to analyze seem like a fairly absurdly small number over the entire surface of the head (especially since in-situ installations of brain monitoring equipment can have up to 500 in a square inch). Awesome work.
ereneon
3 / 5 (1) Sep 22, 2010
EEG has pretty poor resolution even with over 100 electrodes. The signal gets blurred by going through the skull, so adding more electrodes is unlikely to help. I have never seen an EEG based brain machine interface that could do more than about 30 bits/minute.
Journey
4 / 5 (1) Sep 22, 2010
Great work! Not only is it good for giving patients choice and appropriate medical treatment, but it will be so helpful for registered nurses looking after these patients.
AnwerPasha
1 / 5 (1) Sep 22, 2010
That is what I knew for last five years and I tried to tell it to every one during last three years. I tried to do my best and by the grace of God two of such patients are now partially communicating with out such a machine
http://www.paklin...tta.html
trekgeek1
5 / 5 (1) Sep 22, 2010
That is what I knew for last five years and I tried to tell it to every one during last three years. I tried to do my best and by the grace of God two of such patients are now partially communicating with out such a machine
http://www.paklin...tta.html


By the grace of God? You mean the same one who caused this injury right? Start giving more credit to advanced self healing that has evolved over millions of years. And the above article had nothing to do with God, it had everything to do with humans being amazingly clever and implementing advanced technologies to medicine.
Journey
5 / 5 (1) Sep 24, 2010
That is what I knew for last five years and I tried to tell it to every one during last three years. I tried to do my best and by the grace of God two of such patients are now partially communicating with out such a machine
http://www.paklin...tta.html


I'm sorry - that is a lovely story but I can't see how that link shows anything better than what we've been doing in western medicine for years. Patients can often respond as you have described IF they are moving out of the vegetative state and have consistent loving attention - but some remain locked in that state despite all efforts. That is where this technology will be of immense help.

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