In this issue, Walling and Hicks have written a provocative article hypothesizing a concept of consciousness that relates to a system of repeatable and identifiable patterns of elec-trical activity from the central nervous system of various life forms. They conjecture that this pattern of electrical activity, because it has a basic form, indicates that more than chance is involved, and therefore this might indicate a higher influence that might be “consciousness.” They have applied the concept of nonlinear dynamics to neural activity, and where a process can be identified that can be associated with mathematical order, they have identified it as the basis of consciousness. This, of course, is a giant leap of faith, but nevertheless is very intrigu-ing. May we assume that consciousness can be defined in terms of neural activity? Could consciousness be a separate higher function that may require neural activity to access it?
This article raises the question, “What is consciousness?” Consciousness is taken away approximately 27 million times a year in this country in patients undergoing general anesthesia, probably in a similar number of patients undergoing sedation, and who knows in how many people who medicate themselves into oblivion every day. Of course, we all experience a daily loss of consciousness during sleep, but this experience is very variable depending on how far dreams intrude on consciousness. The etiology of dreams is probably controversial enough to spawn another article. Do we know what consciousness is? Certainly we can appreciate that it has much to do with awareness, attention, perception, memory, and cognition, but is it definable? What makes 2 people recount different renditions of the same event? What is the filter that allows some external stimuli to reach the short-term memory circuits and not others? How does this filter fit into our definition of consciousness?
What are you conscious of right now? Perhaps you are conscious of this editorial and are wondering where it is going. You are probably aware of your environment and perhaps your general comfort level. These sensations and emotions almost compete on a second-by-second basis to achieve ascendancy in your mind. Which ones will you allow to become dominant in your thought processes-your hunger or your thirst for knowledge, your discomfort in your environment, or your difficulty in reaching a conclusion in defining consciousness? Consciousness involves all of our senses. The object that reaches our cerebral cortex has a feel to it that may include warmth, texture, color, odor, sound-even if it is the sound of silence-and a visual imprint. One thing that is sure is that your consciousness is totally yours. No one else can know exactly what you are conscious of at a particular point of time.
Consciousness is necessary to be fully aware of our emotions but not to have a specific emotion. We may be completely oblivious of the inputs from our own sensations.
What makes something register and enter our field of consciousness? Can we differentiate between brain and mind? Consciousness is a state of mind that the brain can certainly process and channel into memory circuits, but can we define consciousness in terms of the electrical activity of the brain? Walling and Hicks suggest that we can.
Where does imagination fit into this discussion? Can we imagine as vividly as we can perceive? Many of us cannot because we lack the necessary sensory inputs, but others can bring to consciousness far more than would have been attained in reality. Consciousness is certainly necessary to have a meaningful survival, and level of consciousness is monitored closely in intensive care units.
Consciousness could be defined in terms of human life, and permanent loss of consciousness can be used as a tool to determine continued medical care, yet up to now consciousness has been indefinable. The concept of higher centers versus neural structure is very intriguing. Religious beliefs also play into this concept.