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Practicing Neurologist, New York City; Playwright, Off-Off Broadway Productions, Charter Members; The Gold Ring

The Wizard of I

Consciousness is the fusion of immediate stimuli with memory that combines the simultaneous feeling of being both the observer and the observed into a smooth, enveloping flow of time that is neither truly the past nor the present but somehow inexplicably each of them. It is the ultimate authority and arbiter of our perceptual reality. That consciousness is still an intractable problem for scientists and philosophers to understand is not surprising. Whatever the final answer turns out to be, I suspect it will be an illusion the mind evolved to hide the messy workings of its parallel modular computing.

Neurophysiologists are finding, as they pull ever so slightly at the veil, which shrouds the "Wizard of I," that this indispensable attentive and observant self monitor called consciousness, is dependent upon a trick in overseeing our perceptions. Our subjective sense of time does not correspond to reality. Cortical evoked potentials, electrical recordings, of the normal brain during routine activity have been shown to precede by almost a third of a second the awareness of an actual willed movement or a response to sensory stimulation. The cortical evoked potentials indicate that the brain is initiating or reacting to what is happening far sooner than the instantaneous perception we experience. On a physiological scale, this represents a huge discrepancy that our mind corrects by falsifying the actual time an action or event occurs, thus enabling our conscious experience to conform to what we perceive.

But even more damaging to our confidence in the reliability of our perceptions comes from studies of rapid eye movements, called saccades that are triggered by novel visual stimuli. During the brief moments of these jerky eye movements, visual input to the brain is actively suppressed such that we are literally blind. Without this involuntary ocular censorship, we would be repeatedly plagued with moments of acute blurred vision that would be unpleasant as well as unsafe. From a survival calculus, this would pose an extremely unfavorable disadvantage since it would invariably occur with novel stimuli, which by its very nature required, not the worst but the best visual acuity.

The Wizard's solution to this intolerable situation was to exclude those intervals from our stream of awareness and to replace it instead with a vision extrapolated from what had just occurred to what was immediately anticipated. But consciousness, like a former president, had to come up with an accounting for the erased period. Evolution provided a much longer epic to work out the bugs in its necessary deception than the limited time frame under the gun of a special prosecutor. Instead of trying to hide the existence of the tape, consciousness came up with a far clever trick of obscuring the deletion. It did this by falsifying the time, backdating those necessary moments so that there is no appearance of any gap.

This illusion of visual continuity from inference and extrapolation poses an innate vulnerability in the brain's software that any good hacker can exploit. Magicians, card sharks, three card monte hustlers have made a nice living working this perceptual flaw. In a comic routine, Richard Pyror expressed this best when caught by his wife with another woman. "Who are you going to believe? Me or your lying eyes?"