The Neural Bases of Embodied Human Consciousness
Andrea V. Swift, Ph.D. and S. David Stoney, Ph. D., Richmond County Psychological Services, Augusta, GA 30909 and Dept. of Physiology, Medical College of Georgia, Augusta, GA 30912 (Emeritus)
I. Introduction. Partly as a function of conditioned thinking, seeming absence of satisfactory alternatives, and "folk empiricism" (1) many neuroscientists and neurophilosophers appear to believe that neural activity is necessary and sufficient for embodied human consciousness. This "neuralistic" point of view has been criticized by Stoney at this meeting (2).
Although various accounts have recognized the shortcomings of neuralism (3), most of these, either because of a desire to fully account for human consciousness or due to acceptance of the idea that neurons are able to "represent" things (4), do not successfully emancipate mind from the confines of the skull. Here we present a process philosophical account of the neurobiological bases of consciousness that avoids the solipsistic trap of neuralism. This approach allows us to recognize the limited horizons of classical neural theory (CNT, 2) and brings the accountable human agent into a postcritical era, one that recognizes each persons participation on a difficult planet (5) in a quantum universe (6).
II. Embodied human consciousness. Before the issue of the neuronal contribution to consciousness can be addressed, a tentative definition of consciousness and its historical development must be established. Since consciousness is ordinarily via the body, the most appropriate, honest place to start is from the perspective of embodied consciousness.
Fig. 1. Increases in hominid brain size in relation to the current ice age and transitions in embodied human consciousness. Transition from animal awareness to the archaic and ancestral modes are associated with primary orality, i.e., the development of language. Transitions to compact and differentiated modes are associated with the progressive development of literacy. (Adapted, in part, from Mithen, 7. Also see 5.)
Embodied human consciousness developed in the crucible of the current ice age, the 2 3 million year period of cyclic alternations between long, dry, cold glacial phases and short, wet, warm interglacial phases. During this period, brain size increased in the hominid line (7). However, everything we consciously know about consciousness is a product of the highly literate, self-aware historical period that coincides with the end of the current interglacial phase of the earths climate cycle. The historical record and cultural anthropology shows that modern consciousness developed from preliterate, primary oral beginning where it was dominated by knowledge-by-empathy (8). Primary oral consciousness likely extended from 100,000s of years in the past right up to the compact consciousness of the earliest civilizations, 4,000 to 6,000 years ago. Since then a more differentiated, individuated consciousness more dependent on knowledge-by-analysis has made progressive gains. This contemporary style of consciousness, with its strong self-consciousness, has been associated with a burgeoning development of writing, print, and electronic media.
Today we recognize that we are likely at a transition point from the modern form of embodied human consciousness (EHC) to some variety, yet to be fully determined, of postmodern consciousness. Our trajectory to the present contemporary mind and some of the choices we face are highlighted if we model EHC in a phase space demarcated by self-awareness, awareness of participation, and alienation, as shown in Fig. 2.
Fig. 2. Embodied human consciousness naturally describes an arc from low levels of self-awareness to higher - and ultimately self transcendent - levels. High self-awareness corresponds to a state of postcritical mind where one comes to appreciate that understanding is the recognition of the I in the thou. In this state, ego consciousness is minimized as conscious awareness of participation (universal interconnectivity) increases. Arcs are likely somewhat different for males (upper) and females (lower), but considerable variation is possible. Failure to consciously appreciate the participatory dimension leads to increasing alienation and may ultimately lead to a posthuman condition of solipsistic loneliness and indifference (e.g., 9). The dotted line represents the possibility of unembodied consciousness (10).
III. What do neurons contribute to embodied human consciousness? If, contrary to CNT, neurons are not in the business of mediating internal representations, then what is it that they are doing and how does it engender the neural dependence of EHC? (Here it is presupposed that the reader is familiar with panexperiential concepts. For recent expositions see 11.)
1. Experiential events (a.k.a. actual occasions or "organisms") with"feelings" are the fundamental stuff of the universe. Experience occurs as more-or-less distinct droplets that are comprised of episodes of awareness.
2. Just as gravity instantaneously and ever-presently draws the physical aspects of experiential events together in the physical universe, so too there is an instantaneous, ever-present coalescing of feelings of experiential events in the mental universe. This is referred to as a positive "prehension."
3. Feelings imply awareness! (Awareness necessarily instantiates with feeling.)
4. Experiential events manifest subjective aim (value) in greater or lesser degree. Value is intensified when experiential events join together to form compound individuals. Such is not the case for mere aggregates of experiential events.
5. For a compound individual, feelings and the capacity for awareness that accompanies them compound via prehensions into a dominant occasion of experience (a.k.a. "mind"). Awareness can be said to develop a "depth of field," one that includes at least a degree of self-awareness.
6. Subordinate organisms, e.g., molecules and cells, of a compound individual share the value of the regnant (dominant) occasion of experience of the compound organism.
7. In this quantum universe, all objects, including actual occasions, are images.
8. Prehensive unification between contiguous experiential events generates a joint image and there is thus no need for an "internal" representation of "external" objects.
B. The dual role of neurons in embodied human consciousness
1. Neurons are themselves compound organisms. As such, they are capable of prehensive union with (feeling the feelings of) other cells of the body (organisms), including nearby neurons and glial cells, as well as remote organisms.
2. The prehensive function of neurons is clearly reflected in their responsiveness to sensory stimuli, which better reflects prehension than it does representation (Stoney, 2).
3. The flux of ionic organisms (e.g., Ca++, Na+ & K+) across neural membranes triggers episodes of neural awareness.
4. Neurons are also electromagnetic oscillators and, due to use-dependent strengthening of synapses - which is what action potentials are for - coalesce into functional ensembles (prehensive neural circuits) that oscillate in the gamma range (> 30 Hz).
5. When electromagnetically active, prehensively linked neurons constellate the feelings of the neurons, which includes feeling the feelings of local and remote organisms, into episodes of awareness. These awarenesses constitute the content of conscious awareness for the dominant occasion of experience.
6. The value that is implicit in the dominant occasion of experience is shared with constituent organisms and derives, in part, from the creatures dominant occasion of experience being a constituent of the dominant occasion of experience of the universe. This is the origin of human creativity.
C. What generates episodes of awareness and conscious perception?
1. Since by no stretch of the imagination can the brain be considered to have evolved for conscious perception, it follows that episodes of embodied awareness, which overlap and sum to produce the illusion of a "stream of consciousness," must be generated by activation of neural circuits for movement, actual or potential. Such activations are the physiological equivalent of "yes/no" decisions.
2. As illustrated in the figure below, episodes of awareness have durations appropriate to the intent of the action (actual or potential), hence at any moment many episodes of awareness will be summating.
Fig. 3. The motorsensory theory of awareness. Every brain-originated goal-directed movement initiated by the organism triggers an episode of awareness with a duration appropriate to the intent with which the movement is associated. In this example, tic marks show the onset times for the neural specification of each movement. Episodes of awareness are indicated by the horizontal lines (1 8). Since any brain-caused movement of skeletal muscle will serve to trigger awareness, including those associated with postural adjustments and saccadic eye movements, each seconds worth of experience can be expected to contain many movements and many overlapping episodes of awareness, which sum. Movements occurring during a short period of clock time will ordinarily be governed by the same intent and will thus produce episodes of awareness of about the same duration, e.g., 1 4. Episodes of awareness triggered by movements governed by different intent will be of different duration, e.g., 5. Just as the individual movement components coalesce into a goal directed action, experience (conscious perceptual awareness) takes shape as the summation of overlapping episodes of awareness. Short episodes of awareness (e.g., 1-5) may be subordinate to longer episodes of awareness that began in the past and which will end in the near or far future, e.g., 6. In general, the saliency of episodes of awareness tends to fade, insofar as embodied human consciousness is concerned, the greater the temporal distance from the present, e.g., 7, 8. In this fashion, experience constantly increases, like a long string being rolled up into a ball. But, we tend to lose track of the things that began near the beginning of the string.
3. Episodes of awareness are accompanied by a gating of sensory channels so as to emphasize inputs appropriate to the actual or potential movement. Thus perception is skewed towards salient objects, events, and features. Unobtrusive stimuli for which the sensory channels are not attuned may not be perceived. This accounts for the results of the change and inattention blindness experiments (See ORegan & NoŽ in 3).
A. Consciousness arises as a compounding of the awareness that necessarily accompanies the feeling of feelings by all the organisms that constitute a compound individual.
B. Such compounded awareness necessarily includes prehensions between the dominant occasion of experience and events in the environment, thus consciousness is always about something.
C. Although the nervous system is necessary for mind it is not sufficient and any quest for consciousness in the brain is necessarily misguided.
D. What having a brain does for us is to provide for perception of the world from the perspective of body, i.e., it enables embodied human consciousness.
E. Neural firing (individually, as well as collectively as ensembles) signals prehensive unification.
F. Neural electrical activity signals exterior features, contact, etc., while neural prehension signals interior features (feelings).
G. Always together, these two modes of neural function account for self- and world-awareness.
H. The amplification of self-awareness by culture (12), which accompanied the development of speech, writing, print, and electronic media, has along with the changes in neural organization that accompanied it led to the advent of the contemporary, conceptual mind and self-aware consciousness.
I. Mind, via prehensions, is coextensive with brain, body, and world during an act of perception.
Fig. 4. A process philosophical approach sees mind as coextensive with brain, body and world in a conscious act of perceptual knowing.
Notes and References
1. Konrad Lorenz, in The Natural Science of the Human Species: An Introduction to Comparative Behavioral Research, The "Russian Manuscript" (1944-1948), Agnes von Cranach (Ed.), Robert D. Martin, Translator, Cambridge, MA: The MIT Press, pg.157,1996, accurately expressed the deep nature of our conditioned dualism:
"The concept of the mind is an age-old inheritance of ancient and oriental philosophy. From a tender age, everything to do with the problem of body and mind or soul has been influenced by every word of our parents and teachers, by the entire authority of the Christian religion and idealistic philosophy, by every book written by our great poets, and even by the expressions of idiomatic speech. As a result, the conviction has been hammered into us that the mind is something that exists in its own right and is independent of the body. In addition to this, any contemplation of the mind must necessarily be an introspective contemplation of one's own mind. And this very mind, the presence of an individual ego, is the most certain of all things. Indeed, it is the only thing that is beyond any doubt. The concept of the mind is one half of a pair of opposing concepts which could not exist at all without the counterpart, the concept of a mindless body."
"Folk empiricism" refers to naÔve assessments of causality, a mistaking of correlations for causal relationships, and a failure to appreciate the fallacy of misplace concreteness. An example: Since brain damage alters the content of conscious experience, it follows that the brain is necessary and sufficient for conscious awareness. I ran across the term in David Ray Griffin, Unsnarling the World Knot: Consciousness, Freedom, and the Mind-Body Problem, Berkley, CA: University of California Press, pg.174, 1998.
2. S. D. Stoney, Classical neural theory (neuralism) and its demise, Tucson5, Consciousness Res. Abstr. 75-6, 2002.
3. For example, see Andy Clark, An embodied cognitive science? TICS 3: 345-51, 1999; Susan Hurley, Consciousness in Action; J. Kevin ORegan & Alva NoŽ, A sensorimotor account of vision and visual consciousness, Beh. Brain Sci. 24, 2001; Evan Thompson and F.J. Varela, Radical embodiment: neural dynamics and consciousness, TICS 5: 418-25, 2001; N.J. Wolf and S.R. Hameroff, A quantum approach to visual consciousness, TICS 5: 472-78, 2001.
4. Eric R. Kandel, From Nerve Cells to Cognition: The Internal Cellular Representation Required for Perception and Action, In: Principles of Neural Science, 4th Ed., Eric R. Kandel, James H. Schwartz, & Thomas M. Jessell (Editors), New York: McGraw-Hill, pg. 397, 2000.
5. S. D. Stoney, Iced Neuron (http://david8.home.mindspring.com/Website).
6. John A. Jungerman, World in Process: Creativity and Interconnection in the New Physics, Albany, NY: State University of New York Press, 2001.
7. Steve Mithen, The Prehistory of the Mind: The Cognitive Origins of Art, Religion, and Science, London: Thames & Hudson, pg. 12, 1996.
8. For example, Lucien Levy-Bruhl, How Natives Think; Claude Levi-Strauss, The Savage Mind; Walter J. Ong, Interfaces of the Word; Owen Barfield, Poetic Diction; Eric Havelock, Preface to Plato.
9. Jean Baudrillard, The Vital Illusion, NY: Columbia University Press, 2000; N.K. Hayles, How We Became Posthuman: Virtual Bodies in Cybernetics, Literature, and Informatics, Chicago: University of Chicago Press, 1999.
10. David R. Griffin, Parapsychology, Philosophy, and Spirituality: A Postmodern Exploration, Albany NY:SUNY Press, 1997.
11. David R. Griffin, Unsnarling the World Knot: Consciousness, Freedom, and the Mind-Body Problem, Berkeley, CA: University of California Press, 1998; David R. Griffin et al (Eds.), Founders of Constructive Postmodern Philosophy: Pierce, James, Bergson, Whitehead, and Hartshorne, Albany, NY: SUNY Press, 1993. See also 6.
12. Charles Whitehead, Social mirrors and shared experiential worlds, J. Cons. Studies 8: 3-36, 2001.