We may be getting closer to an answer.
A study announced at the Society for Neuroscience conference reportedly shows how to distinguish between someone who is minimally conscious and someone who is in a vegetative state. Such a determination has been a vexing matter for quite a while. Does a person who is brain damaged, showing no signs of response to external stimuli, have any level of awareness of their situation and surroundings? We may now be able to determine that by measuring the length of brainwaves.
The research for the study included subjecting six brain damaged and unresponsive patients as well as 32 healthy and awake participants to mild electric shocks. Brain activity was then monitored on EEGs. In the brains of healthy patients, an enormous and diverse spike of activity was observed. For the damaged, there was significantly less brainwave response. While the implications of these findings still need fleshing out, they may be useful in cases such as those climacteric moments of determining whether to end life support.
I'm still not sure. I think that the study may be trying to get at something somewhat different from what many colloquially consider consciousness to be. It's a fuzzy, subjective thing, consciousness. Just where is it located in the brain? Is it even within the brain itself? Is consciousness even something that can be studied, measured, or observed in a laboratory sense? Perhaps what we term "consciousness" is really no more than a consensual illusions.
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