Gerald.M.Edelmann
A UNIVERSE OF CONSCIOUSNESS
How Matter becomes Imagination
Basic 2000pg200
Keywords:
What goes on in your head when you have a thought? - ...to take into account that a subjective domain is embodied in each person: Whatever thought I entertain, fragments reflecting my past history are likely to be at the fringe of my consciousness. Given the number and kinds of processes that are going on in parallel in any individual at a particular moment - perceptions, images, feelings, beliefs, desires, moods, emotions, plans, recollections - Is the expression of a thought ever isolated, or is it always accompanied by images, perceptions, sensations, and feelings? To answer this question, let us designate the products of primary consciousness as mental life I and those of higher-order consciousness as mental life II. - With the emergence of a higher-order consciousness through language, there is a consciously explicit coupling of feelings and values, yielding emotions with cognitive components that are experienced by a person - a self. When this coupling occurs, the already complex events of mental life I become intercalated with those of mental life II, which is even more complex. A true subjectivity emerges with narrative and metaphorical powers and concepts of self and of past and future, with an interlacing fabric of beliefs and desires that can be voiced or expressed. Fiction becomes possible. -
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In this chapter, we ask the question: What goes on in your head when you have a thought? Despite the advances in neuroscience, there is no biding the fact that we still do not know the answer in sufficient detail. Some would even say the answer is: "We don't have the faintest idea. " William James was perhaps the first to attempt this exercise seriously. Repeating the exercise in the light of our present understanding of the neural basis of consciousness supports the conclusion that an awfal lot goes on in the brain every time we have a thought, most of it in parallel and of an aweinspiring complexity and richness of assoriation. A good deal of it is information having a complexity that is far beyond the capabilities of present-day computers.
What Goes On In Your Head When You Have A Thought? This question is posed here as if context, environment, and circumstance did not matter but, of course, they do. But even if these factors were all tightly specified, the answer must still be: We do not really know. Suppose we said: WGOIYHWYHAT? and you connected this cryptic sequence with the first letters of the words in the original question. How do your mental contents alter when you make such a connection after you have thought about the meaning of the question? To attempt to answer this question, we construct a hypothetical scenario around the human head within which we have no doubt that thoughts occur. We know the anatomy of human brains, we have pathology and neurosurgery to give us clues, and we undoubtedly will be able to devise new imaging techniques to correlate the activity of the brain with verbal instructions and reports. As long as we are aware of the pitfalls that they entail, we can also make use of first-person reports, introspection, and the consciousness of consciousness.
Before we embark on an exercise in speculative neurology, trying to imagine what goes on in the brain during a thought, we must clear up a few important issues. First, we have to take into account that a subjective domain is embodied in each person: Whatever thought I entertain, fragments reflecting my past history are likely to be at the fringe of my consciousness. Given the number and kinds of processes that are going on in parallel in any individual at a particular moment - perceptions, images, feelings, beliefs, desires, moods, emotions, plans, recollections - it is easy to become confused. If we do not discriminate those processes that are aided by language or for which language may be essential from those that do not require language, we may not be able to learn what a thought entails.
To make this discrimination, we must review the relationship between internalist and externalist views of the mental.
The internalist view (a firstperson view) is that as we interact with the world to establish our beliefs, their content is determined by particular kinds of brain activity that are reachable by introspection.
The externalist view (a third-person view) is that mental life is a construct that is mainly dependent on the interpersonal or social exchanges that are based on language. According to this view, the whole system of language is essential to thought; it is the public aspect of language that gives thought its meaning and that is the basis of mental content. This does not mean that we cannot have "thoughts" without putting them into words. For example, Albert Einstein claimed that his most creative thoughts about physics did not explicitly involve words. Nevertheless, the externalist view claims that to the extent we think about something, our sustained thought is based on the emergence of a mental life through language.
As before, we have to sort out which parts of these two extreme positions are necessary and which are sufficient before we go ahead. It should then be possible to discriminate at least some of the brain processes.that we choose to call mental.
As far as perceptions, images, and feelings are concerned, the internalist view needs no defense. The subjective life of an organism with primary consciousness only (such as a young chimp or a baby before he or she acquires language) is supportable as a process that is uniquely embodied in each individual. And with experience leading to the development of concepts in the nonsentential sense, such an individual can almost certainly connect perceptions and images with feelings in a more or less autonomous manner.
But extended narrative, logic, or highly abstract thought are out of the question. And beliefs and desires in the rich sense of the demands of a true self seeking satisfactions in a social setting based on linguistic exchange remain more or less inaccessible. We would nevertheless hesitate to declare that such an animal has no mental life. What must be conceded is that an individual can have a mental life in the absence of linguistically based beliefs and desires. Only if we restrict the mental to a linguistically based self - the externalist view - do we exclude this possibility. According to the externalist view, a mature chimpanzee with semantic capability bot no true language still cannot think. We doubt this conclusion.
Roughly speaking, the internalist view describes primary consciousness while the externalist position describes higher-order consciousness seen in humans. In humans, both kinds of consciousness operate concurrently, and with the exception of mystical, drugged, or confused states, this simultaneous operation is unavoidable. In contrast, while a nonlinguistic animal can have a mental life, that life is necessarily a restricted one because the animal lacks a self-concept. Although such an animal has a unique mental history, it is not a subject - a self who is able to be conscious of being conscious.
Another disputed issue concerning imagery and imagination must be cleared up before we ask, WGOIYHWYHAT? The dispute over the existence of mental images began with the Greeks and continues unabated to this day. Pictorialists insist that there are mental images, pictures in the head. Propositionalists insist that we may think there are mental images? but the real processes underlying these vague accompaniments are actually propositional and syntactical structures. The pictorialists rely on a strong body of evidence showing that the times required, for example, to carry out the mental rotation of geometric figures or to move mentally from one point on a map to another are linearly related to the actual degrees or distance originally traveled when such acts are carried out "in the real world."
The body of evidence indicating that a "language of thought" does not exist would seem to undercut the claims of the propositionalists. A propositionalist would have to show, for example, how an animal like a dog or a chimpanzee could actually have a language of thought. But even if the inability to make this demonstration favors the pictorialists, are we forced to support the idea of an explicit picture in the head? We all know that when we consciously experience an image, it is usnally vague, partial, and "not real." It is entirely possible to account for the pictorialists' experimental results by considering that the brain generates concepts that are based on a nonrepresentational memory.
To establish a mental relationship, such a memory, which must operate in terms of global mappings based on prior real-world movements, may well be constrained neurally to relate the time taken to carry out its reconstructions to the original times or distances actually traveled. Such a correlation, therefore, does not, in itself, prove the pictorialists' claim. This is not to deny that we consciously experience images, just that the images exist as "representations." We are truly imagining, and short of schizophrenic hallucinations and dreams, we know it. Given the close relationship between perception and memory in a complex brain whose functional connectivity matches the statistics of the environment, it is perhaps no surprise that what we perccive or image in the waking state and what we imagine in dreams is remarkably similar. There is certainly no need to posit that there are actual images in the brain simply because we experience them in conscious states.
Now we come to an important question: Is the expression of a thought ever isolated, or is it always accompanied by images, perceptions, sensations, and feelings? To answer this question, let us designate the products of primary consciousness as mental life I and those of higher-order consciousness as mental life II. There is no harm in this distinction as long as it is understood that these forms of consciousness coexist, overlap, and feed each other. We suspect that no event in mental life II is ever completely divorced from the happenings in mental life I. Consider images: We can have images without words or images with words (or even images stimulated by words). We can have imageless thoughts with or without words. But always in the background, there is the parallel buzz of perception, feeling, mood, and fleeting memories. Of course, mechanisms of attention can come into play, reducing this buzz to near-silence in extreme states of concentration. But most thoughts come into being in the presence of a clamor, however muted, from mental life I.
What keeps a thought going? The answer is likely an intricate combination of ongoing perception, attention, memory, habit, and reward, including aspects of previous learning. Again the drive comes from a mixture of mental life I and mental life II. If someone's thought concerns a recollection, it may be rich in associated imagery. If it concerns willed action, it may or may not be accompanied by any imagery, and if it concerns mathematical objects, it may have associated imagery or just a sequence of habitual symbolic operations without pictures.
If I have the thought "I must go to the store before it is too late," I am deep into mental life II and implicitly assume social interactions, highly-developed language, richly connected memories, and relations to others. The thought may have arisen when I entered the kitchen for a drink of water and remembered belatedly that I promised that I would do the shopping on this day. Entering the kitchen, I see the clock: near closing time, a strong prompting for the thonght that drives me.
Now consider what is going on in my head. First, my basal ganglia, cerebellum, and motor cortex are involved in my walking and in unconscious habitual procedures, such as turning on the water tap. As I move, global mappings are sending signals to my body, arms, and legs, of which I am also mostly unconsciaus. A series of reentrant interactions among my visual maps, parietal cortex, and forebrain areas are involved in immediately translating the signals from the clock face into the time. The activity of the dynamic core plays out a complex contextual scene, along with images from my body. At that moment, a strong surge from mental life I - a feeling of slight fear converted through mental life II into an emotion with necessary cognitive components: anxiety. "The store may be closed." Ascending value systems - the locus coeruleus, basal forebrain nuclei, raphe nuclens, and hypothalamus - send out a particular combination of neurotransmitters that reflect the salience of these various signals. The core must register the neural consequences of this activity - feelings as well as perceptions and recollections.
At this point, a clear elicitation of language and of the true subjective (and emotional) life may emerge: an inner paraphrase (possibly vocalized) "Damn! I must go to the store." And with this paraphrase, the entire memory system of language is engaged, coupled in the core specifically to the temporal cortex; to the frontal cortex for concepts; and, through ports out, to the basal ganglia again for plans to go down to the garage, followed finally by motor cortical signals.
All this still accompanied by little wisps of discomfort from my meal and possibly fleeting memories of opportunities missed. To add a Freudian touch to this little play, we might say that the "reason" I was late to realize my promise concerned a repressed episode related to early punishments by my mother over failed errands, connected to failed performances in later life.
In this account, we are richly into emotions, beliefs, and desires. But notice that whatever the combination, an extraordinary number of brain events are going on simultaneously. Some are directly related to my anxiety, some are subsequently related to my plans to reduce it, and some are simply contemporaneous. In other words, some brain events may be considered causally connected, while others are coincidental, occurring in parallel.
Nevertheless, depending on external events or memories or my reactions to anxiety, what was coincidental and not causally significant may unexpectedly become strongly causal, change my conscious attention, and alter my feelings and actions in an unpredicted fashion.
This near-simultaneous evocation of complexity in the dynamic core and its connection to unconscious routines may be called the Jamesian scenario. The first thing we can say about it is that even in an animal without language, once its nervous system can carry out perceptual categorization and develop conceptual memory, a huge set of possible actions opens up. In an animal with primary consciousness, the activities of the nervous system are driven by value systems, perception, movement, memory, and habit. The reward or threat of a scene consisting of both causally connected and causally unrelated events is assessed in terms of the past experience of that individual animal, and that scene drives behavior. The dynamic, temporally ongoing, bootstrap between a value-category memory and perceptual categorization reflects an individual history, one illuminated at each moment by a remembered present-primary consciousness, mental life I.
With the emergence of a higher-order consciousness through language, there is a consciously explicit coupling of feelings and values, yielding emotions with cognitive components that are experienced by a person - a self.
When this coupling occurs, the already complex events of mental life I become intercalated with those of mental life II, which is even more complex. A true subjectivity emerges with narrative and metaphorical powers and concepts of self and of past and future, with an interlacing fabric of beliefs and desires that can be voiced or expressed. Fiction becomes possible.
The driving force for weaving this remarkable fabric is still provided by the componentry of primary consciousness and memory itself, not to speak of animal appetites. The number of brain areas contributing to the dynamic core and the global mappings that are simultaneously engaged is large, fluctuating, and subject to various linkages. Still, what appears to be a large number of circuits and cells that are actually engaged at any one time is only a small fraction of the number of combinations that are possible in the repertoires of a selectional brain. It is the possibility of enlisting new combinations that gives flexibility to what would otherwise appear to be routine behavior. Like evolution itself, the workings of the brain are a play between constancy and variation, selection and diversity. Given the additional power that language exerts in such a selectional system, meaning can emerge from value through the development of a conscious self.
Is thought necessarily always conscious? Whatever the play between tbe conscious and the unconscious and however strongly unconscious routine may, at times, overwhelm conscious decisions, thought itself, in our view, requires consciousness. To declare that what is mental is conscious and that thinking is conscious does not, however, exclude the enormous irnpact of unconscious learned routines or emotions on thought. Nor does it exclude the possibility that what is threatening to the self can be repressed. The reflections described in chapter 14 make it possible to take this position without claiming constant or exclusive control of our behavior by either conscious processes or unconscious routines.
It will be some time before we can visualize and track in detail the actual brain processes that accompany a thought in all their glory and remarkable complexity. For now, we may conclude that what goes on in the head when each self has a thought is an awful lot. A good part of it for humans is conscious information. We may usefully ask some interesting questions: Where and when in nature did information and then conscious information arise? And how free are humans in their thoughts and knowledge when the informativenesss of higher-order consciousness comes into play? We take up these and other questions in the final chapter.
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