Gerald M.Edelmann A UNIVERSE OF CONSCIOUSNESS Basic 2000

pg. 20 Everyman's Private Theater:  Ongoing Unity, Endless Variety   Our strategy for explaining the neural basis of consciousness is to focus on the properties of conscious experience that are tbe most general, that is, that are shared by every conscious state. One of the most important of these properties is Integration or unity.  Integration refers to the fact that a conscious state cannot be subdivided at any one time into independent components by its experiencer. This property is related to our inability consciously to do more than two things at once, such as adding up a check while carrying on a heated argument.  Another key, and apparently contrastive, property of conscious exterience is its extraordinary differentiation or informativeness:  At any moment, one out of billions of possible conscious scates can be selected in a fraction of a second. We thus have the apparent paradox that unity embeds complexity ­ the brain must deal with plethora without losing its unity or coherence. Our task is to show how it does so. ______________________________________________________   The range and variety of conscious phenomenoloy stretch as widely as one's experience and as far as one's imagination can go; it is everyman's private theater. Books have been written about categorizing the realm of the conscious, and entire philosophical systems have been erected on the basis of attempts to decipher its structure. Consider some obvious characteristics of everyday conscious experience. Conscious states manifest themselves as sensory percepts; images; thoughts; inner speech; emotional feelings; and feelings of will, self, familiarity, and so on.  These states can occur in any conceivable subdivision and combination. Sensory percepts­the paradigmatic constituents of conscious experience­come in many different modalities: sight, hearing, touch, smell, taste, proprioception (the feeling of our own body), kinesthesia (the sense of bodilv positions), pleasure, and pain. Furthermore, each modality comprises manv different submodalities. Visual experience, for example, includes color, form, movement, depth, and so on. Though less vivid and less rich in detail than sensory percepts, thought, inner speech, and conscious imagery are all powerful reminders that a conscious scene can be constructed even in the absence of external inputs. Dreams are the most striking demonstration of this fact. Despite certain peculiarities, such as the dreamer's gullibility, singlemindedness, and loss of self-reflectiveness, dreaming and waking consciousness are remarkably alike: Visual objects and scenes are usually recognizable, language is intelligible, and even the stories that unfold in dreams are highly coherent and can be mistaken at times as true. Consciousness can be passive as well as active and effortful. When we let sensory input freely take possession of our conscious states, paying no attention to this or that in particular, consciousness is as receptive and broad as it is natural and effortless, as for example, when we stroll down the street and enjoy the sights of the town.  On the other hand, when we specifically search for some item in the constant flow of sensory input to which we are exposed, perception becomes an action-oriented activity. The English language has incorporated the distinction between passive and active perception: seeing and watching, hearing and listening, feeling and touching. We are aware of when the more active side of consciousness is called for, since it usually requires an effort on our part.  When we direct or focus attention or search for something in our consciousness; when we struggle to retrieve a memory; when we keep a number or an idea in working memory, perform a mental calculation or imagine a scene, or are deeply immersed in thought; when we plan, plot, or try to anticipate the consequences of our plans and plots; when we initiate an action or choose deliberately among multiple alternatives; when we impose our will; or when we struggle with a problem, consciousness is as active as it is effortful. In most states of consciousness, there is an awareness of being situated or located in time and space and an awareness of our bodies, types of awareness that are clearly based on many different sources of information. There is also often a conscious fringe, which has to do with feelings of familiarity, of being right or wrong, of being satisfied or not. There can be, as well, all those refined discriminations that are the essence of culture and art. Finally, conscious experience varies in its intensity; the global level of alertness can range from relaxed slumbering to the hypervigilant state of the fighter pilot in action, and sensory perception can be more or less vivid. There is the well-known ability, called attention, to select or differentially amplify certain conscious experiences to the exclusion of others. Furthermore, consciousness is inextricably linked to certain aspects of memory, as we emphasize in later chapters. Indeed, immediate memory, which lasts for fractions of a second, is often equated with consciousness itself.  Working memory, the ability to "keep in mind" and manipulate conscious contents, such as phone numbers, sentences, and positions in space, for a few seconds is clearly closely related to consciousness. This subdivision and analysis of different aspects of conscious experience could be extended ad libitum. One can spend a lifetime analyzing and refining one or another facet of one's conscious experience, from the appreciation of art to the discrimination of wines, from the exercise of will and concentration of thought to the attainment of blessed states of pure, unencombered perception. As interesting as the rich phenomenology of consciousness may be, we will not discuss its multitudinous aspects further. We simply acknowledge that the possibIe modalities and contents of conscious experience, although not arbitrary, are exceedingly numerous.  Instead of analyzing the everchanging situations played out in everyman's private theater, we concentrate on a few principles that, like the three unities of classical drama­time, place, and action­they all share. In this chapter, we therefore focus on those fundamental aspects of conscious experience that are common to all its phenomenological manifestations: privateness, unity, and informativeness.   THE IRREPRESSIBLE WHOLENESS OF BEING:  PRIVATENESS, UNITY, AND COHERENCY OF CONSCIOUS EXPERIENCE In the foreword to his classic, The Integrative Action of the Nervous System, Charles Sherrington expressed the personal and unitary character of consciousness with his usnal eloquence:  "Each waking day is a stage dominated for good or ill, in comedy, farce, or tragedy, by a dramatis persona, the 'self'. And so it will be until the curtain drops.... Although multiple aspects characterize [the conscious self, this self is a unity."  William James also recognized that the unitary, private nature of consciousness is its foremost property. Notwithstanding the teachings of some Eastern religions, he concluded that each conscious event is a process that has a single "point of view" and has definite boundaries and cannot be shared: In this room­this lecture room, say­there are a multitude of thoughts, yours and mine, some of which cohere mutually, and some not. They are as little each-for-itself and reciprocally independent as they are all belonging together. They are neither no one of them is separate, but each belongs with certain others and with none beside. My thought belongs with my other thoughts, and your thought with your other thoughts.... The only states of consciousness that we naturally deal with are found in personal consciousness, minds, selves, concrete particular I's and you's.... The universal conscious fact is not "feelings and thoughts exist", but "I think" and "I feel."

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