Notes and Suggestions towards A Theory of Consciousness

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Abstract:
We open by considering briefly some of the characteristics of ordinary
consciousness which seem to have gained consensus acceptance among those studying the
problem of how the physiological systems we are attain subjectivity. We then look at the
Thalamo-Cortical system so aptly described by Newman and offer some observations on the
roles of feedback processes, propagation delays, resonant systems and Llinas' (et alia)
40Hz oscillations. These factors, we argue, provide a way of locking together the
phenomenal, subjective world and the physiological substrate on which consciousness runs.
We then discuss the role of culture in forming brains and consciousnesses, and close with
the suggestion that there is no "Hard Problem": that the phenomenal and
physiological representations are two sides of the same coin. |
1. What is
Consciousness ?Click here to
expand yours.
This will take you places you have never been beforeż
To know the world and to act independently within it and to do things for oneself.
Reflection within on the patterns within as well as reflection off the world by
interacting with others and by projecting into the world for purposes of generating
feedback.
1.1. Consciousness is the "I", the "self" that
we all know, from which we view the world and interact with it, that sense of (to quote
John Searle) "subjective qualitative states of awareness, sentience or feeling"(1). In the 17thCentury Rene Descartes showed
that no matter to what extent our senses might be deceived there would still remain a
something which could be called "myself" even if it were utterly deceived as to
the existence of any one or any thing else. I suppose his "cogito ergo sum"
might have been better put if he'd said I am deceived therefore I am. William James (2a) (in the late 19thCentury) put it as having a sense of a personal
consciousness that is ours, not something that we share [though in passing, how we
consider this against the matter of the social construction of our world view remains to
be discussed].
1.2. Everything we know is a function of experience, either through sense
perception or reflection upon that experience. The mind or the "I" is born empty
of knowledge of the world. As John Locke (3) described it we are born
"tabula rasa" (or a 'blank slate'). It is only by our experience of the
world that we gain ideas of it. There are no "innate ideas".
"Let us then suppose the Mind to be, as we say, white Paper, void of all
characters, without any Ideas; How comes it to be furnished ?....To this I answer, in one
word, from Experience... Our observation employed either about External sensible objects;
or about the Internal Operations of our Minds, perceived and reflected by our selves...
These two are the Fountains of Knowledge from whence all the ideas we have, or can
naturally have, do spring. [Locke. A Treatise of Humane Knowledge, 1721, p67]
It is the data of sensation that have the qualities or "qualia" which are the
stuff of our subjectivity, that which we know.
1.3. Consciousness is a function of the state of our central nervous system,
i.e. the physiology is the substrate upon which consciousness runs. To quote
William James in his Text Book of Psychology, 1892 (2b):
"The immediate condition of a state of consciousness is an activity of some sort
in the cerebral hemispheres... One has only to consider how quickly consciousness may be
abolished by a blow on the head...[or] by a full dose of alcohol...to see how at the mercy
of bodily happenings our spirit is... Destruction of certain definite portions of the
cerebral hemispheres involves losses of memory and of acquired motor faculty of quite
determinate sort...Taking all such facts together, the simple and radical conception dawns
upon the mind that mental action may be uniformly and absolutely a function of
brain-action, varying as the latter varies, and being to the brain-action as effect to
cause." [James, 1892, pp5-6]
1.4. Our state of consciousness:
a/ is always changing as we are exposed to continually novel
sensations.
b/ is selective of what it pays attention to, and
c/ provides a sense of temporal continuity which the normal day-to-day
changes of sleep and wakefulness, as well as abnormal changes such as unconsciousness, do
not interrupt.
1.5. Paul Churchland (author of "The Engine of Reason; The Seat of
the Soul") (4) has described some salient aspects of
consciousness, which we would need to explain in a theory of consciousness.
a/ Short-term memory and its decay.
b/ Directable attention, or conscious control over what we attend to and
what we do.
c/ Multi-valent comprehension through "mulling" or reflection.
d/ Independence from sensory input in say, daydreaming.
e/ The disappearance of consciousness during sleep.
f/ Unity across the senses and unity over time.
1.6. Robert Kirk (5) (of Nottingham University) has developed a
concept of what he calls the "basic package" of capacities that an
organism must have for it to be conscious. This is first about being able to collect
information which is specifically intended for the organism's own use, and then about its
capacity to decide what to do with that information. There is a package of related
activities which apply to this collecting information.
a/ The organism must be able to use the information.
b/ The organism must be able to initiate and control its activity on the
basis of the information it collects.
c/ The organism must be able to assess the information for its usefulness
or interpret it.
d/ The organism must be able to assess the situation it is in so that it
can decide how to respond or whether it should respond.
1.7. Our ability to respond to novelty in active and constructive ways is
considered to be somehow over and above the mere 'irritability' of the senses and the
body's reflexivness to sensations which may or may not then have conscious impact. The
plant which follows the sun across the daily sky is not able to refuse to do that. It has
no opportunity to decide whether or not it will not respond to the tropism of the sun. It
can only do it, there is no capacity to act independently of this tropism.
1.8. So ultimately the problem for a theory of consciousness is to explain how
it is that the physical system that we are, this bundle of cells and organs and nerves,
can have subjectivity, can behave independently, can do things for itself and can
respond to input in a way that takes account of whim and ideology rather than simply
reacting to current conditions. This is the question that David Chalmers (6)
asks in his formulation of the "Hard Problem":
"Why is it that physical processing in the brain, no matter how sophisticated,
should give rise to any subjective inner life at all? Why couldn't that have all gone on
in the dark? That's the real mystery." [Chalmers: Brain Project interview]
1.9. Two views of the relationship of the brain to the mind or consciousness
seem to have developed since Descartes. The first is the "dualistic" view that
consciousness somehow exists independently of the physical world and body. This position
derives from Descartes but is perhaps more akin to the modern religious view of the
"soul". The second is the physicalist view which says that in some manner
consciousness is a direct function of the physiology. This view was espoused early on by
de la Mettrie in his very radical 17th Century work "Man a Machine" (7).
My argument is essentially that it is not necessary to dualise the mind away from
the brain, but that normal physiological functioning of the brain includes, within the
array of its processes, that which we consider to be consciousness. That is, that
consciousness is an inescapable result of an immensely complex but highly
organized information processing and representation system. |
2. How we know.
2.1. The multiple ways of talking about consciousness are representations.
So we have the diverse array of philosophical representations, the physiological
representation, the phenomenological representation, the neural net representation, etc.,
which I argue are all simply different ways of talking about the same thing.
Representation is transformation of information from one modality to another. Within a
physiological discussion (representation) of sensation; colors, sounds, feelings and
other qualia are phenomenological representations of those sensations coming in through
the eyes and ears and proprioceptive senses. Each layer of information processing in the
brain is a transform of the input representation into a new representation. The very act
of seeing is in fact a mediated process through a series of layers of representations of
which we are largely unconscious into a series of representations which are bound (usually
inextricably) with sense representations from the other modalities; hearing, touch, etc.
and of which we are in some way aware or conscious. What we know is entirely
mediated by the sense organs and the brain. What we know of the world is inference. So
we have two areas of study, on the one hand that which physical and biological scientists
do, and on the other, that which philosophers and psychologists and cognitive scientists
do. For simplicity I will call these the physiology and the phenomenology of
consciousness.
2.2. Phenomenology
is the study of what we actually know of the world; qualia, the stuff, the
contents of consciousness, rather than the study of what we infer about the world
based on that phenomenology, which is the business of the physical sciences. How we know
it is one aspect of the phenomenology. We perceive and report our perceptions. We imagine
and reflect on the contents of the phenomenology. We report and interact through language
which we gain through the culture as we grow up. Culture and language mould our
consciousness and render us human. But, ultimately, we see colors, hear sounds, feel
emotions all through the use of the brain. Consciousness, whatever its relationship to
the physiology, requires that physiology as the substrate on which it runs.
2.3. So it is the study of the physiology of the brain that is
our first task in developing a theory of consciousness. Whatever we may think about the
phenomenology, whether we take a mystical view or a physicalist view of consciousness,
there is still the information processing and as far as anyone can tell all information is
necessarily embodied in something physical. |
3. Physiology
3.1. As Hughlings Jackson (8) said
in 1876:
"All nervous centers, from the lowest to the very highest (the
substrata of consciousness), are made up of nothing else than nervous arrangements,
representing impressions and movements...I do not see of what other materials the brain
can be made." [Hughlings Jackson "West Riding Asylum Reports" 1876 p267].
And William James asserts that there is a complete parallelism between
the arrangements of nerves and the ideas to which they project:
"The muscles and the sensitive points are represented each by a
cortical point, and the brain is nothing but the sum of these cortical points, to which,
on the mental side as many ideas correspond." [James 1891, p30] Thus it is the
"motor and sensory ideas variously associated [that] are the materials of the
mind". [James, ibid]
3.2. So we need to know something of the physiology and
the organization of the brain to enable us to at least see on what it is that
consciousness operates, that is the substrate or the embodiment of consciousness. [And
there are some considerable differences in the implications of these two terms for our
final theory].
3.2.1. For the sake of discussion, the system of the brain can be
broken up into a number of interlinked parts. These are, essentially, the bodily
connections through the spinal cord and the brain stem, the reticular activating system at
the top of the brain stem, the sensory modalities and their connections to the cortex
through a central relay station and the cortex, to which all sensory data may be sent and
in which much of the interpretive and planning and control processing is done. It is the
central relay station which will interest us most here. This central relay system is known
as the thalamus. It, in linkage with the cortex, the basal ganglia, the
hypothalamus, the hippocampus and several other structures, forms the thalamo-cortical
system.
3.3. In an excellent review, published as an electronic seminar
on the Internet, Jim Newman (9) has demonstrated the functions of the thalamo-cortical system and its tributaries in
being the site (or better, the system) most likely for the embodiment of the major
functions of day-to-day consciousness and the processes of integration and control of the
informational structure through which we have our place in the world.
3.3.1. To summarize the thalamo-cortical system. The thalamus
acts somewhat as the hub in a wheel, the spokes of which are nerve bundles traveling
from
the body periphery (carrying sense and bodily data) and which are then relayed up into the
cortex and cortical association areas for interpretive processing. All of the sensory
pathways (with the exception of the olfactory) are routed through the thalamus. For
example, the optic tract runs from the retina, through the optic chiasm to the thalamus
and thence into the lateral geniculate from where it is distributed into the occipital (or
visual) cortex at the back of the brain. Auditory data from the inner ear is relayed
through the medial geniculate into the auditory cortex in the temporal lobes. All of the
face and body's proprioceptive data is routed through the thalamus on its way to the
somato-sensory cortex. These are ascending pathways.
3.3.2. At the same time there is a vast array of nerve bundles
descending from the cortical areas onto the intralaminar nuclei and the nuclear
reticularis in the thalamus. These descending pathways act to gate the sensory data
being presented to the cortex and it is in this capacity for the cortex to control what
data it is being sent at any moment that we can find the function we call selective
attention. Also nerve bundles from the frontal and prefrontal areas go via the basal
ganglia to the thalamus where they are integrated with sensory data to help in the control
of motor functions.
3.4. Essentially what's going on is that there is an array of
massively connected feedback control circuits, organized horizontally around
the thalamus and the basal ganglia and various emotion function nuclei and vertically
between the cortex and the thalamus. The former (the horizontal) give behavioral
control
and the latter (the vertical) provide sensory control, especially in preventing the cortex
from being overwhelmed by sensory input.
3.5. Also, in the cortex are vast arrays of intra-cortical nerve
connections which probably provide the capacity to associate different sensory modalities
and to interpret grouped or bound collections of data from different senses that allow one
to, for example, recognize that the sounds you hear are coming from the mouth you see
speaking to you, and that the individual whose mouth you are watching is saying things
that have meaning. |
4. The organization of things
4.1. But it is the purpose of the descending pathways which I
want to concentrate on for a moment. These descending pathways act as a control system.
The data the cortex is being fed from moment to moment is determined or controlled by the
cortex. We have operating here a kind of feedback network which turns the whole
thalamo-cortical system into a self-regulating process. This capacity for
self-regulation forms the basis for almost all levels of life, from the regulation of
cellular metabolism to the behavior of individuals in society.
4.2.1. So what is this feedback thing? In a system which,
say, acts as a buffer for a subsequent processing system the results of the process are
compared with the needs of the system and any difference (or error) is analyzed
in such a
way as to provide an indication to the buffer of what is needed by the subsequent
processor. This feedback can be either negative (i.e. inhibitory) with respect to the
input, or positive (i.e. excitatory) with respect to the input.
 |
Wiener's generalized feedback process (from Norbert Wiener. Cybernetics,
1948 (10)) |
4.2.2. In the brain, the cortex feeds back to the
thalamus a complex set of inhibitory and excitatory controls which allow it to have a
measure of control over what it is being fed, thus it does not get overwhelmed by the
immense amounts of sensory input which are to a large extent unnecessary for its survival.
If this feedback control system did not exist it would be as though we lived permanently
in the grip of an LSD experience, and we and all of society would collapse. But not with
binaural beat audio technology. Click Here 
4.3. In an engineering context an electronic amplifier is
regulated by a certain proportion of the output being fed back into the input as an
inverted (or negative) representation of that input. But, and this is a crucial point, it
takes time for this process to occur. It takes time for the electrons to travel through
the circuit to the output. This is called propagation delay. If the frequency of
the signal, and the propagation delay through the amplifier, is such that the output of
the amplifier, when fed back to the input is positive (or non-inverted) with respect to
the input then the amplifier becomes an oscillator. You've heard this numerous times when
a microphone is placed in front of the speaker to which it is being fed. The combination
of feedback and propagation delay causes a circuit to reverberate or act as an oscillator.
It becomes a resonant circuit which may be considered as holding the information in
the circuit for longer than the period of the original information. This is a form of
memory.
 |
Video Feedback shows the effect of propagation delay in creating an oscillating system
which can undergo considerable perturbation and still be stable. |
4.3.1. In the thalamo-cortical reverberatory
system this will be what we know as short-term memory. But there is a bigger system
here. Myriads of feedback pathways are operating, propagation delays of all sorts of
intervals are involved and so we have a very complex, but organized and self-regulating
set of systems which is the activity of our brains. The period of the resonance might well
be in the order of several hundred milliseconds, which is similar to human reaction time.
This short-term memory period is our present, our being-in-the-world. We don't feel the
world as being a succession of instantaneous states but as a period of connectedness with
things before they become the past.
4.4. Now Rodolfo Llinas and others, particularly using
magneto-encephalography, have remarked on a rhythmical 40Hz pattern traveling
"across the entire cortex" (Newman). This is a field being sensed by the
detector with a duration of 25 milliseconds before it collapses again. (Is this some sort
of function of the refractory period of a neuron's activation sequence?) This rhythmical
field will be the result of coordinated neural activity which happens in steps (or
cycles). In the engineering world we call this a clocked system. Clocked systems grab the
state of the system and hold it till the next clock cycle where they grab the next state.
The state of the system is refreshed every 25 milliseconds.
4.4.1. Given the variable propagation delays through different
sensory pathways a means of synchronizing and holding various input so that they can be
bound together and become as different aspects of a single event is provided by a clocked
system. This will also provide what is perhaps the so called eidetic memory into which
we dip for confirming what was just said for example. Or perhaps from which we
"hear" ourselves speak and know what we are saying.
4.4.2. Presumably also some aspects of the past state of the
system are retained by the current sample and fed back into the current sample via
descending processes from the cortex, enabling the sense of being in a continuing
phenomenal field of the present.
4.5. But this would only apply to the conscious system, what we
are actively attending to, the stuff of our consciousness currently. Now, obviously, we
all also have instant response requestors and reflexes which operate at the immediate
sense level and use express routes into the attention setting sub-system. So there may be
higher processing frequencies, or clock rates, with other faster (for example music
listening) systems being active. Though the massively parallel nature of all sensing
sub-systems presumably enables this full sensory awareness to occur at slower speeds than
otherwise necessary, (that is, at sampling rates below what would be necessary in serial
sampling for sensory awareness).
4.6. In the magneto-encephalographic frame this field of
activation, showing up as 40Hz oscillations, is a matter of nerve propagation and the
activities of electrons and electro-magnetic fields. I want to suggest that in order to
describe what goes on in these reverberatory fields we might use the concept of phase
modulation as a means for describing the process of the large-scale behavior
of an organized complexly interacting system. That is, the electro-magnetic/chemical activity of
the system is describable within phase-modulation terms.
4.6.1. I will elaborate: in a dynamic system, phase is a
description of the timing aspects of various parts of the system with respect to one
another. If we look at an event at one moment, look away to something else and then look
at the first event again we will see that event at a different phase of its
process. Phase describes sets of relations over time and as these sets of relations are
altered by, say, contextual factors, the system may be said to be phase modulating.
4.6.2. Behavior impacts on the nervous system which is
undergoing this immensely complex phase-modulation live. The thalamo-cortical system, fed
by perceptual input and the brain stem, and supported, analyzed and "driven" by
the cortex is an immense feedback network which, if happening in an electronic circuit
environment, could only be considered a resonating circuit. Notice that propagation delay
will play an important role such that the propagation delay and its results in the adding
and subtracting of waveforms (i.e. phase modulation) contributes to the resonance of a
system.
4.6.3. Any input, fed forward from sensory input systems or fed
back into the circuit from cortical association and control structures will affect the
"shape" of the overall reverberating circuit. The amount of any signal in the
circuit will be affected by the intensity of the input and the feedback structures.
4.6.4. Signals being propagated through the thalamo-cortical
structure or any other structure in the brain are embodied in nerve processes and grouped
as assemblies, the magnitude of which are determined by the needs of the active system at
the time (a la Greenfield (11)). These nerve processes have at least an
electronic aspect (as well as a neurochemical aspect) and as such will create an
electro-magnetic field within and about the physiological structures of nerve assemblies.
This electro-magnetic field is what is detected in magneto-encephalography, and because it
is embodied in a physical structure it will display a kind of "shape" showing the
phase relationships among different representational aspects of the current condition of
conscious knowing and the near-conscious data contained in various support structures'
informational processes. Any instantaneous state of the system can be described by a phase
diagram (albeit an extremely complex one) and as the system changes in real time,
according to new input, reverberant memory and associations, the phase state of the system
will be modulating. Thus a phase modulation description will map the ongoing changing
states of the physiology and of consciousness.
4.6.5. It should be obvious from what I have been saying here
that the changes in phenomenal consciousness generated by a new input, a new decision
or whatever, will take place in actual physiological nerve processes and these
physiological changes will thus change the electron transport conditions in the nerves.
Electron transport can be detected as electro-magnetic fields and so we have directly
detectable physical concomitants of phenomenological activity. Of course our
detection equipment would need to have extraordinarily sophisticated signal processing to
tease out the contribution of any particular input or thought to the overall
shape of the
field, but in principle it could be done.
4.6.6. The nervous system is an electro-chemical system
undergoing phase modulation and propagation delay and resonance with the world. The period
of the propagation delay may well be a couple of hundred milliseconds, enough to give us
the present we are always with. The buzz of representations and productions in the brain
are us and we represent them phenomenologically and investigate their physiology and their
physics. We are inside this resonance, we live it, we are it. |
5. A couple of observations on phenomena
I would like to mention a couple of phenomenal events which say
interesting things about some of the conditions of this reverberatory process of being
conscious.
5.1. First. At Tucson II, Daniel Dennett gave a demonstration of
a visual phenomenon in which a person looking at an image on a monitor screen was
simultaneously watched for eye movement, or saccades, as the subject focused
on different
aspects of the image presented. When one such saccade occurred the image displayed was
changed in some way, usually quite strongly, for example the color of a coat worn by
someone in the image would change color. The person being tested would almost invariably
be unable to detect any change in the image, being unable to describe what had changed. It
was usually not until told about the change, that they would suddenly see it.
5.1.1. Now the saccade is of interest for me here. I would
suggest that the saccade happens in the collapsed period of Llinas' 40Hz rhythmical field
and thus we don't see anything during that period. As we are triggered by difference (i.e.
the activity of things changing, the actual changing) as our primary comparator, the
slower cortical comparators don't have the data of a noticed change to set them up (or
off). One of the reasons for this to happen is that the collapsed period, in some sense
means no seeing (or whatever). During a saccade the shifting pattern of light on the
retinas moves very fast and all sorts of confusing data would be provided and so it might
be necessary that a number of critical circuits, particularly motion detectors, be
disabled while the flick of the eye occurs so that we don't "spin out".
5.2. Secondly, I want to mention another visual phenomenon that
shows some interesting relations here. I've often noticed, oddly enough mostly while
sitting in restaurants, that a person will walk past an open doorway, say walking along
the street, and I will realize that I only noticed them being in the doorway after there
had already developed a significant space behind them, i.e. between them and the door jam
on the edge from which they had entered the scene. So this must mean that it takes a
considerable period for the recognition of most mundane, non-threatening events, possibly
an interval of 25 milliseconds, which is the period of these putative "sampled events
in consciousness". |
6. Now, back to the cortex itself: Addressing
memory.
6.1. In the cortex there is also a layer of horizontally
connected nerve processes. These are the association pathways which store and associate
all the array of stimulus which has become memory. I wonder whether a neuron assembly
which is involved in memory processing could be able to assist in the remembering of
different things overlaid onto the one network by controlling the triggering of patterns
of data through different synaptic structures applied to a particular neuron. Nerve nets
are programmed dynamically by weightings that might also recede to zero (off) just as they
might vary only slightly around a mean value. The same nerve net will produce a great
array of different outputs depending on the weights applied at its inputs and so a number
of different, say, "concepts" could be represented by the same nerve net,
depending on the representations of input and recurrent data available in all the
contextual, i.e. surrounding, neural elements in the net. These "patterns of
activation" [P.M.Churchland's phrase] could be seen as a kind of addressing structure
in which the values represented serve as addresses (or pointers) for concepts further
upstream.
6.2. A neuron structure will then be able to assist in the
storage and retrieval of a number of different memories from an assembly through this
variable addressing structure. This addressing structure will presumably emulate the
original patterns of the laying down of any particular memory trace. In a sense the
addressing structure is the memory and it triggers activators (or representation
processors) to work in particular ways in assembling different memories (that is
re-assembling the past).
6.3. These addressing structures are set down by experience, by
learning, by practice in the environment particularly through childhood where the basic
patterns are set down. The culture, in which the individual grows up, sets up the meme
structure which is actively embodied on the inter-neuronal synaptic structure. Memes then
become addressing structure with a phenomenological frame or representation. Notice the
role of culture. |
7. The Culture dimension
7.1. What of this cultural dimension? Culture and society provide
the sources of the modulating activity of our day-to-day lives: the
external/social/perceptual and the internal/generative/reflective: We are interactive
systems within the culture. We have an active relationship with others and the world
around us be it in real space, mythic/cultural space or cyberspace.
7.2. Each of us has active relations with people and things. Our
social interactions operate in the face-to-face, the personal, the social; and the remote
(e.g. publishing a book, or producing art). They operate at many scales, and depending how
much social power our output has, within greater or lesser segments of the society or
culture. We generate output, from an embrace to the Magna Carta, and this output has some
sort of impact on some other entities in the culture. The people and structures upon whom
this output impacts will then, should they so chose, be able to produce responses which
are feedback to us, if we choose to receive it. So one is in an active relation with
the world around: what we do changes it, what others do changes us. Now the content of
this activity has meaning and this is achieved through the operations of our brains,
bringing the sensory input into consciousness.
7.3. Culture modulates and guides the growth and development of a
living conscious entity. Culture shapes the content and the interpretive structures of the
brain. We grow into our current self(-identity). What we experience shapes the maturation
of the nervous system and the growth of our "minds".
7.3.1. As an infant develops any move of the muscles stimulates
afferent nerves. This stimulation initiates myelination of the nerve fiber, and also
asserts in the brain the existence of the fiber and its mapping into whichever cortical
area it is involved with. Adjacent fibers carrying stimuli (signals) from adjacent areas
on the sensing surface are similarly myelinated and mapped into the cortex. The infant
will at first only sense inchoately. As more input occurs mappings will be consolidated
and refined. At the same time efferent nerves are carrying signals which initiate
movements, the nerves are myelinated by their use and the muscles are stimulated to
develop in their ability to respond. As muscles move they impact with external objects and
stir internal proprioceptive sensors, thus returning signals to the appropriate sensory
cortexes which carry feedback on the muscle action.
7.3.2. In the brain nerve processes from sensory areas feed data
to other areas of the brain including direct, and higher level, motor control areas. When
the infant hand impacts upon an object the grasping reflex leads to attempted interaction
with the object which further stimulates the sensory systems. If grasping is not possible,
say because of the size of the object, then other action will tend to take place to
compensate in some way, by, say, opening the hand more. The activity of reaching and
touching stimulates the nerves in the arms to grow and myelinate and stimulates the
differentiation and mapping of the nerves in the brain which handle sense data, feeding it
into control centers, differentiating and mapping these nerves. This provides a substrate
for finer control over the muscles. A feedback loop of refining control by successive
approximation results, our aim becomes better and better; and soon we are reaching,
holding, pulling, crawling and so on better and better. Maturation of the brain and
consciousness takes place in direct relation with maturing of the body.
7.4. If the brain is seen as a numerically immense collection of
organized systems of nerves and their interconnections and the supporting wetware that
keeps everything operating, we can represent it as a collection of neural nets in which
the whole range of distributed processing tasks, which we use either in or out of
consciousness, function to keep us operating in the world. All the patterns of stimulation
which flow through this massively parallel distributed processing system are originated in
the body's ongoing becoming in the world, or in external data from the world and our
reflections upon that. So the connectionism that develops among neural processes is
determined by the stimulus they receive and the kinds of systems available for handling
that stimulus. If the so-called "weightings" of the synaptic connections are
dependent upon the exercise of stimulated neural processing systems then the world as we
know it will be embedded in the data structures set up within these neural nets. At birth
there will be little beyond the basic propensities of the brain: to learn to crawl, to
walk, to recognize a face, to acquire language: no content as such. The contents of
consciousness and thus our being in the world are embedded in us by stimulus we acquire by
being in the world.
7.4.1. Setting up the addressing patterns/structures suggested in
section 6 is started here, at birth. Socialization of the infant into the family, language
and society at large, establish and enable consciousness in ourselves as individuals. The
surrounding culture is an intrinsic and necessary part of the process of the emergence of
consciousness in all humans beings. An entirely isolated individual would fail to
develop many of the aspects of consciousness which I canvassed in section 1.
7.4.2. Daniel Dennett talks of units of meaning, memes,
that are the content of our consciousness and no doubt active below consciousness as
well. Among other things the brain is a system for acquiring, elaborating and reporting
memes. Their propagation in society is enabled by their operation within the system of our
brains (the processes of our physiology) in which memes have their duration and their
change and flow. The physiology is the skein within which these things are embodied, given
substance. Ideas only exist in brains and in the cultural, in-the-world-manifested
projections of our minds, i.e. the models we project onto the world and the things we make
of the world, be they books or buildings.
7.5. The contents of the brain may well be like the contents of a
language, codes for those things apprehended, as words are codes, signs standing in for
the object. There is only the complex of processes (the patterns of activation, the
addressing structures) standing for the object in the brain. There is a sense in which the
known world is not congruent with what is "out there" in that everything we know
of the world is contained in the processing system which we call the brain. Computer
graphics and imagery are often spoken of as being "simulacra" of things in the
world, the "virtual" as distinguished from something supposed to be real, but
all we know of the world partakes as simulacra. What is contained in the brain/body/self
is (an encoding of) the current flow through, and resonance's of, the data of the world:
social, physical; in light and sound and smell.
7.5.1. What we know is not the world, but our sensory
processing of its waves and disjunctions. It is our culturally derived representations of
what we have experienced. When an infant is born and commences interacting with all
about it its nerves are sparked into the commencement of maturation. The discernment of
the buzzing, blooming confusion reaches focus and sound is differentiable enough to be
from specifiable sources and resolves into language and light resolves into recognition.
The brain is in a very strong way being wired up (more correctly the pathways not
stimulated drop away, atrophy). The internal structures of the nervous system physiology
are the coat-hangers upon which the coats of the culture are being hung. Each individual
will be unique, having been exposed to a unique stream of stimulus and context. The
wardrobe of self will be entirely distinctive made up from the available elements and
styles of the culture surrounding. If people don't wear shirts then shirts are unknown.
One might argue that our representations as internally generated actually project out
meaning onto the fabric of unknowability.
7.5.2. Our physiology develops via interaction with its
environment, both in terms of its immediate physical environment as contacted via movement
and touch (for the drawing out of mobility and engagement), and in terms of the
development of the social-interactive capabilities that render our individual
consciousnesses human. As visual and auditory sensations become sorted out the nerves
establish the connectionism of their nets, and personal, cultural and linguistic
capacities develop. We are dependent on the stimulation we receive from the world for the
growth of our physiology as much as through any drive on the part of the physiology
itself. It is as if growth were drawn out of us by the world, the fabric of the source of
all our sensations. This process never really stops, the ripples and ramifications of our
being in the world feed, enfold, inform the world that we know, informing, enfolding and
feeding us. In this larger scale, culture is the driver of the "phase
modulation" of the physiology of consciousness.
7.6. Emotions and chemical modulation. Our existence in the world
requires input from the world, we are not closed systems. We require food and air and
sunshine and stuff and these have various effects upon our physiology. We also engage in
social contact and this also has impact on the body's physical being. Physical/social
events produce physiological responses both as the process of moving our arms or our
mouths and as the biochemical impacts of the metabolism which enables a muscle to move.
The brain monitors this behavior and feeds back into the body with desires and needs
which also produce biochemical events. All of this stuff starts to become a (somewhat
simplified) look at the role of emotions in consciousness. The appearance of highly
emotional stimuli will change our hormonal chemistry balance and this at least in some
sense will have a modulatory impact on consciousness. If we feel hungry our consciousness
will try and direct us towards feeding. |
8. In conclusion:
A summary of what I think might be going on to produce consciousness.
In a complex flow of world processing, if we change (arbitrarily) the
state or the sign of one aspect, then the timing of this change will effect/affect the
phase-shape of the waveform of that processing flow. In humans this change of state is
psychological/phenomenological: we have decided to alter the conditions, but it alters the
physiological conditions as a direct result. Which came first? The decision or the
conditions requiring the decision. It matters little, they come from both directions,
embedded in the physiology where all this goes on.
This assumes that we have an identifiable system through which this
world-processing occurs. In Bernie Baars' terms this is the Global Workspace (12), in
James Newman's and Rudolfo Llinas' and John Taylor's and Joseph Bogen's terms the
thalamo-cortical system (9) is the work horse, the structure through
which this occurs. The two classes of representation used here map directly onto each
other. The downward control flow from the cortex is the pathway through which a
psychological decision (e.g. a change of plans) is translated into the global
consciousness and the physiology.
A formal description (a model only, an abstraction) of the particular
planning process will have decision points within the streams of data where, so to speak,
"collision" or merging occurs between streams. One might call it a functional
description of the processes, or functions, engaged at any particular moment. Conjunctions
between ideas will occur, new perceptions enter, some demanding immediate attention,
priority. Planning needs to be altered: "Don't bump into me!". The link between
perception and planning, between hearing and interpretation is through the
thalamo-cortical system. What to attend to is determined as much by input, (e.g. an
interruption) as by high level decision about what word to put next.
The real time "results" of "running" the function
description is the process of being of an individual. (And on another scale, where the
exchange and flow of ideas and goods in a society describe the dynamic "state",
the fluid flow, of that society).
We are a phenomenological state machine implemented on a physiological
substrate. Consciousness will be a subsection of this state-machine running day-to-day,
moment-by-moment thoughts and memory, attentiveness and active sensory and motor control.
We change the neural states and assemblies and we change the weightings of synaptic
connections and this is going to change the process and pathways of electron flow which
modulates the waveform of the system description live, on the fly. Modulating the waveform
of our on-going process is a function of the phase relationships of the contributory data
streams. It happens over time.
This complex wave shape of "immense dimension" modulating over
time will produce a self-sustaining resonance. Our sense of continuity shows much depth in
this resonance.
These resonant circuits will run in both localizable
and global levels.
Are the smaller ones, the localizable, directly a part of consciousness or more the
(source of) contributory streams? Are they entities in themselves (Daemons)? Are they
ideas? concepts? thoughts and emotions that keep coming back to us? Is there a system with
oversight which I call self: "myself"? We are probably a complex of these things
which it is the job of the psychiatrist, for example, to repair when damaged or disrupted
or just grown too distorted to allow us to keep operating.
The "explanatory gap" invoked by David Chalmers in his
formulation of the Hard Problem is the issue of how to explain the presence of
subjectivity, i.e. the phenomenal, in an otherwise materialist, objective, representation
which is physiology. Descartes originally created this problem when he split off the mind,
the self, from the otherwise mechanical description of the body. Having made the
separation (which I suspect was more of a political act than anything else) he then had to
explain how the mind could control the body. His invoking the Pineal body as the means
through which this control occurred was shown to be unsatisfactory and so the problem as
formulated remained. We now see it in Chalmers' Hard Problem which is really a question of
how do the two kinds of representation map onto each other.
As I have said above "The buzz of representations and productions
in the brain are us and we represent them phenomenologically and investigate their
physiology and their physics. We are inside this resonance, we live it, we are it."
There is no Hard Problem, consciousness is simply the ongoing process of
being (inside) an immensely complex reverberatory circuit with a stripped down, simplified
set of attentions and interpretations which we apply at any particular moment. Our active
control over what we are doing from moment to moment is a physiological activity. We know
what we want to do and we do what's necessary to achieve it by the self-regulation of what
comes onto the "global workspace" the "stage" of consciousness
[Baars]. I don't see this as some sort of competitive process but a co-operative process
which we are inside and actively engaged in. Self-regulation is not competitive but
constructive.
The only dualism necessary is the dualism of two classes of descriptive
representation, the phenomenological and the physiological. They talk about the same
process and we can see this mapping relation in the phase modulation of the
electro-magnetic fields produced by nerve activities which are a direct affect of a change
of phenomenological state, (e.g. a change of mind, a new decision).
The only hard problem we really have is getting our own heads around
this idea that just as the complex interrelations between molecules and cells and their
organized structuring and dynamics produces living things so the organized dynamics of the
vast neuronal structure of our brains as in the world will also "go live" and
this is being conscious.
References and Links
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1. John Searle: presentation to Tucson II. 2a.
William James. (1890) Principles of Psychology
2b. William James. (1892) Textbook of Psychology
3. John Locke. (1721) An Essay on Human Understanding
4. Paul Churchland. (1995) The Engine of Reason, the Seat of the
Soul. A Philosophical Journey into the Brain. M.I.T. Press.
5. Robert Kirk (1996) The Basic Package in The
Brain Project
6. David Chalmers (1996) The Hard Problem in
The Brain Project
7. de la Mettrie L'Homme Machine
8. Hughlings Jackson. West Riding Asylum Reports 1876
9. James Newman (1997) Putting the Puzzle Together, Part I: Towards a
General Theory of the Neural Correlates of Consciousness. in Journal of
Consciousness Studies, 4 1, pp47-66.
10. Norbert Wiener (1948) Cybernetics, or Control and
Communication in the Animal and the Machine, Wiley.
11.. Susan Greenfield (1996) Neural Assemblies[GRNFIELD.HTM - MISSING]
in The Brain Project |
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