Some patients diagnosed as being in a vegetative state showed signs of brain activity during brain scans, according to a new study that researchers said could change the way science views patients thought to have lost all awareness.

It was a small study -- of just 54 patients with severe brain injury, 23 in a vegetative state and the rest in a less severe "minimally conscious state." But the British and Belgian researchers think the findings could be quite significant, offering clues for better diagnosis of people with brain injuries and development of a technique to communicate with them.

Patients were placed in an MRI scanner and asked to imagine hitting a tennis ball and walking from room to room in their homes. Four of the 23 vegetative patients responded to the commands by showing brain activity on the scanners.

And one man was even able to detailed yes and no questions about his life before his injury.

The research, appearing in the latest New England Journal of Medicine, also raises ethical dilemmas about how modern medicine should treat such patients, this NYT story explains. 

It also comes with plenty of caveats: Only a small number of patients responded. The scanning technology needs work and isn't ready to be a diagnostic tool just yet. And as an accompanying editorial by Dr. Allan H. Ropper of Brigham and Women's Hospital in Boston states, brain activity as seen on the scanner is not indicative of a "stream of thought," i.e. memory, self-awareness and reflection. 

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