There was a very interesting article on the New Scientist website, about the question of consciousness. The author, Ray Tallis, argues that we have failed to explain how consciousness equates to neural activity inside the skull because the task is self-contradictory.

Tallis, a Professor of geriatric medicine at the University of Manchester, and Fellow of the Academy of Medical Sciences, challenges the "orthodoxy", held by most neuroscientists and philosophers of the mind, that very soon scientists will be able to explain the mystery of human consciousness in terms of the activity of the brain. He stresses, however, that his argument is not about technical limitations; rather it is about the deep philosophical confusion embedded in the assumption that if you can correlate neural activity with consciousness, then you have demonstrated they are one and the same thing, and that a physical science such as neurophysiology is able to show what consciousness truly is.
 
Trapped Inside 24/11/2009
 
This is the sort of things you see in films or read in novels –"Johnny Took his Gun" by Dalton Trumbo or "The Patient" by Georges Simenon are but two of the examples that spring to mind– but the report that circulates all media since yesterday is very real. A paralysed Belgian man who doctors thought was in coma for 23 years was conscious all along. It was only recently that a scan showed that his brain was "almost entirely" functioning. You can read the BBC report here.

I cannot begin to grasp what it must have been this experience for this poor man, but I can very vaguely imagine. A recent book and film used the metaphor of a diving bell. You are inside your body as if you are inside a diving bell. It's alright when you can control your diving bell. You swim around and interact with all other beings in diving bells you encounter. Suddenly something happens and you loose control of the diving bell. Your life as such is not threatened; but you can't communicate any more, you can't interact. You are trapped inside.