While it would be wonderful for the likes of astral projection and 'special abilities' to be true, the evidence is at best very weak, and at worst the work of self confessed hoaxers who's aim was to show just how easy it is to 'demonstrate' such abilities, even in supposedly tightly controlled conditions.

I have taken hallucinogens in the past, and am well aware that our consciousness is capable of so much more than the everyday, but those conscious states I experienced were directly related to the chemical changes those substances made to my brain, and subsided as those chemical effects wore off. Other drugs obliterate consciousness altogether, again directly related to the chemical changes that they create in the brain. Neurological experiments suggest that activity takes place in the brain BEFORE we experience consciousness related to it, or at least we can be easily fooled into believing we have made a conscious decision about a particular piece of behaviour, when infact it has already been set in motion at an unconscious level.

Thus, whatever function consciousness serves, all evidence points to it most definitely being directly related to brain state, rather than existing as an independent phenomenon