Unpicking Consciousness

New studies done on how anesthesia affects the brain are helping us to understand the mystery of human consciousness. We are pretty unique animals, after all - our powers of self-awareness and intellect have allowed us to profoundly change the entire face of the planet, and to pull off audacious feats of engineering such as this.

It appears that there is no real "seat of consciousness" - but that consciousness arises somehow from the interactions among different parts of the brain.

Brown says that some drugs will decrease the frequency of brain waves seen in EEG readings, resulting in slow, regular oscillating waves across large areas of the brain. Other drugs cause certain areas to show fast, regular oscillations. Because anesthesiologists usually give a cocktail of drugs to each patient, these effects can happen simultaneously. The result, says Brown, is like a jammed signal: "Either way, [the different parts of the brain] can't communicate."

A popular sleep aid, Ambien, has also been shown to help some patients locked in a persistent vegetative state back to full consciousness. We don't yet have all the answers, but the parameters of the question are getting more and more interesting.

The Mystery Behind Anesthesia via the MIT Technology Review