Ingram - Theatre of the Mind

T HERE is something unnerving about writing a book about a subject that even the experts cant define. Welcome to consciousness. It really shouldnt be that hard: we may not think much about consciousness, but we all know whats it like not to have it. When you are sleepingas long as youre not dreamingyou are unconscious. If you faint or get knocked out, you lose consciousness. In those situations, as far as you know, there is nothing much going on in your head. Actually, there is much going on in your brain, but you are unaware of it. Awareness and consciousness are closely related, if not synonymous.

Getting knocked out or slipping into deep dreamless sleep are the most common excursions from consciousness, but there are others. If you have a general anaesthetic for surgery, you are unconscious as long as the anaesthetic is in effect. At least, most people seem to be, but there are unnerving reports from patients like this one: I could see the surgeons at the end of the operating table and I thought, ? my God, they are going to operate on me and Im awake. I tried to tell them but I couldnt speakcouldnt move it was the worst experience of my life. Another wrote, The consciousness was terrifying. The desperate animal terror of trying to signal ones conscious state to someone, but unable to twitch a bloody eyelash.

Less dramatically, patients can sometimes remember or recognize certain words that were spoken while they were under the anaesthetic. In extreme cases, derogatory comments made about the patient (This ones todays Blue Plate special) or the alarmed reaction of the surgeons (Gee, this could well be a tumour ) have been linked to delayed postoperative recovery, suggesting that the words were heard in some sense, though they apparently never actually reached consciousness. Sometimes post-operative hypnosis does reveal that the patient did hear and can remember comments made in the OR.

But does this suggest that there is a kind of consciousness while under anaesthesia? Not necessarily. Because muscle relaxants that induce paralysis are given alongside the anaesthetic, patients suffer, as in those real-life accounts, but also are unable to signal in real time that they remain aware, if indeed they are. As a result, scientists are forced to rely either on indirect indicators of consciousness (such as patterns of brain waves) while the patients are apparently knocked out or on the patients memory afterwards, jogged by hypnosis or not. Neither provides the kind of hard and fast reliable data youd like. This is the subjectivity problem that arises again and again in consciousness research: my thoughts and feelings are my own. No matter how cleverly and vividly Im able to describe them to you, that description is necessarily incomplete, my consciousness at least partly inaccessible to you. For all we know we are all completely aware during surgery but forget it all after. Who can prove that wrong?

What about those momentary lapses during freeway driving, in which you suddenly realize that you have no memory of the last ten kilometres? They seem at first glance to be a short-lived version of the same sort of thing, but while you may not remember your driving, you werent unconscious. You were talking on your cellphone, listening to the radio or lost in other thoughts, and each of those requires that you be conscious and attentive to them. The fact that your mind had wandered from the routine of driving to other, more interesting things is a striking example of the ability of consciousness to select or reject whatever mental activities it wishes. It also illustrates how a thought or image can move easily into consciousness or back out of it, taking only fractions of seconds to do so Thats what happens to your awareness of driving, at least for a while.

This doesnt necessarily mean you were accident-prone during that time on the road, although how would you ever be able to find out? Any sudden emergency would snap you back to full consciousness in an instant, and even if it didnt, it likely wouldnt make any difference: your foot would already be on the brake, directed there unconsciously (more about this later). Even if your momentary lack of awareness did cause you to react marginally more slowly, youd likely never know. What would you have to compare that moment with? Its also possible that once you noticed something was happening and snapped back to full awareness mode, any memory that your mind had been wandering might have been erased.