Researchers have identified signs of awareness in a patient in a vegetative state, a discovery that could perhaps lead to devices enabling such individuals to interact with others.
The research, led by scientists from the University of Cambridge and the Medical Research Council Cognition and Brain Sciences Unit, measured the electrical activity over the scalp of 21 patients diagnosed as vegetative or minimally conscious and 38 healthy volunteers.
In doing so, they found that one vegetative patient was able to filter through unimportant information to focus on relevant words they were told to pay attention to. Taking this one step further, they used functional MRI (fMRI) to find that the same patient was able to follow simple commands to imagine playing tennis.
Three other minimally conscious patients reacted to novel but irrelevant words; however, they were unable to selectively focus on the target word.
Based on these results, the scientists believe that some vegetative or minimally conscious patients may be able to direct their attention to surrounding noises.
"Not only did we find the patient had the ability to pay attention, we also found independent evidence of their ability to follow commands -- information which could enable the development of future technology to help patients in a vegetative state communicate with the outside world," said Dr. Srivas Chennu from the University of Cambridge.
The study, Chennu explained, is part of a greater effort to better understand the brain functioning of patients currently unable to interact with the outside world.
"In order to try and assess the true level of brain function and awareness that survives in the vegetative and minimally conscious states, we are progressively building up a fuller picture of the sensory, perceptual and cognitive abilities in patients," the researcher said. "This study has added a key piece to that puzzle, and provided a tremendous amount of insight into the ability of these patients to pay attention."