Scanner Reveals Brain Dead Show Signs Of Awareness
Nov 11, 2011 15:35
A new study published in The Lancet suggests that brain dead people might not be as unaware as most people would like to believe.
Researchers used an EEG machine to examine brain waves and found that
three of 16 vegetative patients could understand what they heard and
follow instructions. Here's more on the experiment from Smart Planet:
The “new” brain scanner is an electroencephalogram (EEG), which,
ironically is an older, less expensive machine than the kind of brain
scanner that has been used to look for consciousness in vegetative
patients: a functional magnetic resonance imaging (fMRI).
The research team, led by Damian Cruse and Adrian M. Owen of the
University of Western Ontario, hooked 16 people in a vegetative state up
to an EEG, a common medical device that measures electrical activity
in the brain through electrodes placed on a person’s head.
The scientists then asked them to imagine that they were making a
fist with their right hand whenever they heard a beep. In another
exercise, they had them imagine that they were wiggling their toes when
they heard a beep.
The scientists compared their EEG results to those of healthy people who were asked to imagine the same thing.
Three of the supposedly brain-dead people showed the same two brain
patterns (one for the hand, one for the toes) that the healthy study
subjects displayed during the experiments: Activity for both showed up
in the premotor cortex, the region of the brain that sets physical
movements in motion.
The subjects who displayed the brain activity of conscious people
made up 20% of the study group. They were men (aged 29, 35 and 45) who
had been pronounced vegetative for the past three months to two years.
Such findings could help scientists in deciding whether a gravely injured person is actually in a vegetative state or just unable to respond.