The Competitiveness of Nations
in a Global Knowledge-Based Economy
December 2002
Walter J. Freeman
Consciousness, Intentionality, and Causality
Journal
of Consciousness Studies
6 Nov/Dec. 1999
143-172
Index
Figure 1: Linear Causality of the Observer
Figure 2: Circular Causality of the Self
2. Level 1: The circular causality of intentionality
3. Level 2: The circular causality of reafference
Figure 3: The Primitive Forebrain
(a)
Patterns of Neural Activity
Figure 4: Limbic System - Dynamic Architecture
4. Level 3: Circular causality among neurons and neural masses
5.
Circular causality in awareness
6. Consciousness viewed as a system parameter controlling chaos
(b) Current Limitation of Neurodynamics
7. Causality belongs in technology, not in science
(a) Limitations of Linear Causality
(b) Applicability of Circular Causality
8. Anthropocentricity in acts of human observation
(a) Intentionality as property of material objects
(b) Suppression of feedback mechanisms
10. Applications of causality in medical technology
11. The Technology of Mental Illness
12. The science versus the technology of self-control
To explain how stimuli cause consciousness, we
have to explain causality. We can’t
trace linear causal chains from receptors after the first cortical synapse, so
we use circular causality to explain neural pattern formation by
self-organizing dynamics. But an
aspect of intentional action is causality, which we extrapolate to material
objects in the world. Thus causality
is a property of mind, not matter.
1. According to behavioral theories deriving
from pragmatism, Gestalt psychology, existentialism, and ecopsychology,
knowledge about the world is gained by intentional action followed by
learning. In terms of the
neurodynamics described here, if the intending of an act comes to awareness
through reafference, it is perceived as a cause.
If the consequences of an act come to
awareness through proprioception and exteroception, they are perceived as an
effect. A sequence of such states of
awareness comprises consciousness, which can grow in complexity to include
self-awareness. Intentional acts do
not require awareness, whereas voluntary acts require self-awareness.
Awareness of the action/perception
cycle provides the cognitive metaphor of linear causality as an agency.
Humans apply this metaphor to objects
and events in the world to predict and control them, and to assign social
responsibility. Thus linear causality
is the bedrock of social contracts and technology.
2. Complex material systems with distributed
nonlinear feedback, such as brains and their neural and behavioral activities,
cannot be explained by linear causality. They
can be said to operate by circular causality without agency.
The nature of self-control is
described by breaking the circle into a forward limb, the intentional self,
and a feedback limb, awareness of the self and its actions.
The two limbs are realized through
hierarchically stratified kinds of neural activity.
Actions are governed by the
self-organized microscopic neural activity of cortical and subcortical
components in the brain. Awareness
supervenes as a macroscopic ordering state, that defers action until the
self-organizing microscopic process has reached a closure in reflective
prediction. Agency, which is removed
from the causal hierarchy by the appeal to circularity, re-appears as a
metaphor by which events in the world are anthropomorphized, making them
subject to human control.
Department of Molecular & Cell Biology
TEL 510-642-4220 FAX 510-643-6791
wfreeman@socrates.berkeley.edu
3. What is consciousness?
It is known through experience of the
activities of one’s own body and observation of the bodies of others.
In this respect the question whether
it arises from the soul (Eccles, 1994), or from panpsychic properties of
matter (Whitehead, 1938; Penrose, 1994; Chalmers, 1996), or as a function of
brain operations (Searle, 1992; Dennett, 1991; Crick, 1994) is not relevant.
The pertinent questions are - however
it arises and is experienced - how and in what senses does it cause the
functions of brains and bodies, and how do brain and body functions cause it?
How do actions cause perceptions; how
do perceptions cause awareness; and how do states of awareness cause actions?
Analysis of causality is a necessary
step toward a comprehension of consciousness, because the forms of answers
depend on the choice among meanings that are assigned to “cause”: (a) to make,
move and modulate (an agency in linear causality); (b) to explain, rationalize
and blame (cognition in circular causality without agency but with
top-down-bottom-up interaction); or (c) to flow in parallel as a meaningful
experience, by-product, or epiphenomenon (noncausal interrelation).
4. The elements of linear causality are shown in Figure 1 in terms of stimulus-response determinism. A stimulus initiates a chain of events including activation of receptors, transmission by serial synapses to cortex, integration with memory, selection of a motor pattern, descending transmission to motor neurons, and activation of muscles. At one or more nodes along the chain, awareness occurs, and meaning and emotion are attached to the response. Temporal sequencing is crucial; no effect can precede or occur simultaneously with its cause. At some instant each effect becomes a cause. The demonstration of causal invariance must be based on repetition of trials. The time line is reinitiated at zero in observer time, and S-R pairs are collected. Some form of generalization is used. In the illustration it is by time ensemble averaging. Events with small variance in time of onset close to stimulus arrival are retained. Later events with varying latencies are lost. The double dot indicates a point in real time; it is artificial in observer time. This conceptualization is inherently limited, because awareness cannot be defined at a point in time.
5. The elements of circular causality are shown in Figure 2. The double dot shows a point moving counterclockwise on a trajectory idealized as a circle, in order to show that an event exists irresolvably as a state through a period of inner time, which we reduce to a point in real time. Stimuli from the world impinge on this state. So also do stimuli arising from the self-organizing dynamics within the brain. Most stimuli are ineffective, but occasionally one succeeds as a “hit” on the brain state, and a response occurs. The impact and motor action are followed by a change in brain structure that begins a new orbit.
A succession of orbits can be conceived as a
cylinder with its axis in real time, extending from birth to death of an
individual and its brain. Events are
intrinsically not reproducible. Trajectories
in inner time may be viewed as fusing past and future into an extended present
by state transitions. The circle is a
candidate for representing a state of awareness.
6. Noncausal relations are described by
statistical models, differential equations, phase portraits, and so on, in
which time may be implicit or reversible. Once
the constructions are completed by the calculation of risk factors and degrees
of certainty from distributions of observed events and objects, the assignment
of causation is optional. In
describing brain functions awareness is treated as irrelevant or
epiphenomenal.
7. These concepts are applied to animal
consciousness on the premise that the structures and activities of brains and
bodies are comparable over a broad variety of animals including humans.
The hypothesis is that the elementary
properties of consciousness are manifested in even the simplest of extant
vertebrates, and that structural and functional complexity increases with the
evolution of brains into higher mammals. The
dynamics of simpler brains is described in terms of neural operations that
provide goal-oriented behavior.
In the first half of this essay (Sections 2-6) I
describe the neural mechanisms of intention and reafference and learning, as I
see them. I compare explanations of
neural mechanisms using linear and circular causality at three levels of
hierarchical function. In the second
half I describe some applications of this view in the fields of natural
sciences. The materials I use to
answer the question, what is causality?, come from several disciplines,
including heavy reliance on neurobiology and nonlinear dynamics.
In the words of computer technologists
these two disciplines make up God’s own firewall, which keeps hackers from
burning in to access and crack the brain codes.
For reviews on neuroflaming I
recommend introductory texts by Bloom and Lazerson (1988) on “Brain, Mind and
Behavior”, and by Abraham et al. (1990) on “Visual Introduction to Dynamical
Systems Theory for Psychology.”
2. Level 1: The
circular causality of intentionality
8. An elementary process requiring the dynamic
interaction between brain, body and world in all animals is an act of
observation. This is not a passive
receipt of information from the world, as expressed implicitly in
Figure 1.
It is the culmination of purposive
action by which an animal directs its sense organs toward a selected aspect of
the world and abstracts, interprets, and learns from the resulting sensory
stimuli (Figure 2).
The act requires a prior state of
readiness that expresses the existence of a goal, a preparation for motor
action to position the sense organs, and selective sensitization of the
sensory cortices. Their excitability
has already been shaped by the past experience that is relevant to the goal
and the expectancy of stimuli. A
concept that can serve as a principle by which to assemble and interrelate
these multiple facets is intentionality. This
concept has been used in different contexts, since its synthesis by Aquinas
(1272) 700 years ago. The properties
of intentionality as it is developed here are (a) its intent or directedness
toward some future state or goal; (b) its unity; and (c) its wholeness
(Freeman 1995).
9. Intent comprises the endogenous initiation,
construction, and direction of behavior into the world, combined with changing
the self by learning in accordance with the perceived consequences of the
behavior. Its origin lies within
brains. Humans and other animals
select their own goals, plan their own tactics, and choose when to begin,
modify, and stop sequences of action. Humans
at least are subjectively aware of themselves acting.
This facet is commonly given the
meaning of purpose and motivation by psychologists, because, unlike lawyers,
they usually do not distinguish between intent and motive.
Intent is a forthcoming action, and
motive is the reason.
10. Unity appears in the combining of input from
all sensory modalities into Gestalten, in the coordination of all parts of the
body, both musculoskeletal and autonomic, into adaptive, flexible, yet focused
movements, and in the full weight of all past experience in the directing of
each action. Subjectively, unity may
appear in the awareness of self. Unity
and intent find expression in modern analytic philosophy as “aboutness”,
meaning the way in which beliefs and thoughts symbolized by mental
representations refer to objects and events in the world, whether real or
imaginary. The distinction between
inner image and outer object calls up a dichotomy between subject and object
that was not part of the originating Thomistic view.
11. Wholeness is revealed by the orderly changes
in the self and its behavior that constitute the development and maturation of
the self through learning, within the constraints of its genes and its
material, social and cultural environments. Subjectively,
wholeness is revealed in the striving for the fulfillment of the potential of
the self through its lifetime of change. Its
root meaning is “tending”, the Aristotelian view that biology is destiny.
It is also seen in the process of
healing of the brain and body from damage and disruption.
The concept appears in the description
by a 14th century surgeon, LaFranchi of Milan, of two forms of healing, by
first intention with a clean scar, and by second intention with suppuration.
It is implicit in the epitaph of
Ambroise Paré, 16th century French surgeon: “Je le pansay, Dieu le guarit” (I
bound his wounds, God healed him). Pain
is intentional in that it directs behavior toward facilitation of healing, and
that it mediates learning when actions have gone wrong with deleterious,
unintended consequences. Pain serves
to exemplify the differences between volition, desire and intent; it is willed
by sadists, desired by masochists, and essential for normal living.
12. Intentionality cannot be explained by linear
causality, because actions under that concept must be attributed to
environmental (Skinner, 1969) and genetic determinants (Herrnstein and Murray,
1994), leaving no opening for self-determination.
Acausal theories (Hull, 1943;
Grossberg, 1982) describe statistical and mathematical regularities of
behavior without reference to intentionality.
Circular causality explains intentionality in terms of
“action-perception cycles” (Merleau-Ponty, 1945) and affordances (Gibson,
1979), in which each perception concomitantly is the outcome of a preceding
action and the condition for a following action.
Dewey (1914) phrased the same idea in
different words; an organism does not react to a stimulus but acts into it and
incorporates it. That which is
perceived already exists in the perceiver, because it is posited by the action
of search and is actualized in the fulfillment of expectation.
The unity of the cycle is reflected in
the impossibility of defining a moving instant of ‘now’ in subjective time, as
an object is conceived under linear causality.
The Cartesian distinction between subject and object does not appear,
because they are joined by assimilation in a seamless flow.
3. Level 2: The
circular causality of reafference
13 Brain scientists have known for over a century that the necessary and sufficient part of the vertebrate brain to sustain minimal intentional action, a component of intentionality, is the ventral forebrain, including those parts that comprise the external shell of the phylogenetically oldest part of the forebrain, the paleocortex, and the underlying nuclei such as the amydala with which the cortex is interconnected. These components suffice to support identifiable patterns of intentional behavior in animals, when all of the newer parts of the forebrain have been surgically removed (Goltz, 1892) or chemically inactivated by spreading depression (Bures et al., 1974). Intentional behavior is severely altered or lost following major damage to these parts. Phylogenetic evidence comes from observing intentional behavior in salamanders, which have the simplest of the existing vertebrate forebrains (Herrick, 1948; Roth, 1987) comprising only the limbic system. Its three cortical areas are sensory (which is predominantly the olfactory bulb), motor (the pyriform cortex), and associational (Figure 3). The latter has the primordial hippocampus connected to the septal, amygdaloid and striatal nuclei. It is identified in higher vertebrates as the locus of the functions of spatial orientation (the “cognitive map”) and temporal orientation in learning (“short term memory”). These integrative frameworks are essential for intentional action into the world, because even the simplest actions, such as observation, searching for food or evading predators, require an animal to coordinate its position in the world with that of its prey or refuge, and to evaluate its progress during evaluation, attack or escape.
The Primitive Forebrain
(a) Patterns of Neural Activity
14. The crucial question for neuroscientists is,
how are the patterns of neural activity that sustain intentional behavior
constructed in brains? A route to an
answer is provided by studies of the electrical activity of the primary
sensory cortices of animals that have been trained to identify and respond to
conditioned stimuli. An answer appears
in the capacity of the cortices to construct novel patterns of neural activity
by virtue of their self-organizing dynamics.
15. Two approaches to the study of sensory
cortical dynamics are in contrast. One
is based in linear causality (Figure
1). An experimenter identifies a
neuron in sensory cortex by recording its action potential with a
microelectrode, and then determines the sensory stimulus to which that neuron
is most sensitive. The pulse train of
the neuron is treated as a symbol to ‘represent’ that stimulus as the
‘feature’ of an object, for example the color, contour, or motion, of an eye
or a nose in a face. The pathway of
activation from the sensory receptor through relay nuclei to the primary
sensory cortex and then beyond is described as a series of maps, in which
successive representations of the stimulus are activated.
The firings of the feature detector
neurons must then be synchronized or ‘bound’ together to represent the object,
such as a moving colored ball, as it is conceived by the experimenter.
This representation is thought to be
transmitted to a higher cortex, where it is compared with representations of
previous objects that are retrieved from memory storage.
A solution to the ‘binding problem’ is
still being sought (Gray, 1994; Hardcastle, 1994; Singer and Gray, 1995).
16. The other approach is based in circular
causality (Figure 2).
In this view the experimenter trains a
subject to cooperate through use of positive or negative reinforcement,
thereby inducing a state of expectancy and search for a stimulus, as it is
conceived by the subject. When the
expected stimulus arrives, the activated receptors transmit pulses to the
sensory cortex, where they elicit the construction by nonlinear dynamics of a
macroscopic, spatially coherent oscillatory pattern that covers the entire
cortex (Freeman, 1975, 1991). It is
observed by means of the electroencephalogram (EEG) from electrode arrays on
all the sensory cortices (Freeman, 1975, 1992, 1995; Barrie et al., 1996; Kay
and Freeman 1998). It is not seen
in recordings from single neuronal action potentials, because the fraction of
the variance in the single neuronal pulse train that is covariant with the
neural mass is far too small, on the order of 0.1%.
17. The emergent pattern is not a representation
of a stimulus, nor a ringing as when a bell is struck, nor a resonance as when
one string of a guitar vibrates when another string does so at its natural
frequency. It is a phase transition
that is induced by a stimulus, followed by a construction of a pattern that is
shaped by the synaptic modifications among cortical neurons from prior
learning. It is also dependent on the
brain stem nuclei that bathe the forebrain in neuromodulatory chemicals.
It is a dynamic action pattern that
creates and carries the meaning of the stimulus for the subject.
It reflects the individual history,
present context, and expectancy, corresponding to the unity and the wholeness
of intentionality. Owing to dependence
on history, the patterns created in each cortex are unique to each subject.
18. The visual, auditory, somesthetic and
olfactory cortices serving the distance receptors all converge their
constructions through the entorhinal cortex into the limbic system, where they
are integrated with each other over time. Clearly
they must have similar dynamics, in order that the messages be combined into
Gestalten. The resultant integrated
meaning is transmitted back to the cortices in the processes of selective
attending, expectancy, and the prediction of future inputs (Freeman, 1995; Kay
and Freeman, 1998).
19. The same wave forms of EEG activity as those
found in the sensory cortices are found in various parts of the limbic system.
This similarity indicates that the
limbic system also has the capacity to create its own spatiotemporal patterns
of neural activity. They are embedded
in past experience and convergent multisensory input, but they are
self-organized. The limbic system
provides interconnected populations of neurons, that, according to the
hypothesis being proposed, generate continually the patterns of neural
activity that form goals and direct behavior toward them.
20. EEG evidence shows that the process in the
various parts occurs in discontinuous steps (Figure 2), like frames in a
motion picture (Freeman, 1975; Barrie, Freeman and Lenhart, 1996).
Being intrinsically unstable, the
limbic system continually transits across states that emerge, transmit to
other parts of the brain, and then dissolve to give place to new ones.
Its output controls the brain stem
nuclei that serve to regulate its excitability levels, implying that it
regulates its own neurohumoral context, enabling it to respond with equal
facility to changes, both in the body and the environment, that call for
arousal and adaptation or rest and recreation.
Again by inference it is the neurodynamics of the limbic system, with
contributions from other parts of the forebrain such as the frontal lobes and
basal ganglia, that initiates the novel and creative behavior seen in search
by trial and error.
21. The limbic activity patterns of directed arousal and search are sent into the motor systems of the brain stem and spinal cord (Figure 4). Simultaneously, patterns are transmitted to the primary sensory cortices, preparing them for the consequences of motor actions. This process has been called “reafference” (von Holst and Mittelstädt 1950; Freeman 1995), “corollary discharge” (Sperry 1950), “focused arousal”, and “preafference” (Kay and Freeman, 1998). It compensates for the self-induced changes in sensory input that accompany the actions organized by the limbic system, and it sensitizes sensory systems to anticipated stimuli prior to their expected times of arrival.
22. The concept of preafference began with an
observation by Helmholtz (1872) on patients with paralysis of lateral gaze,
who, on trying and being unable to move an eye, reported that the visual field
appeared to move in the opposite direction. He
concluded that “an impulse of the will” that accompanied voluntary behavior
was unmasked by the paralysis. He
wrote: “These phenomena place it beyond doubt that we judge the direction of
the visual axis only by the volitional act by means of which we seek to alter
the position of the eyes.”. J.
Hughlings Jackson (1931) repeated the observation, but postulated
alternatively that the phenomenon was caused by “an in-going current”, which
was a signal from the non-paralyzed eye that moved too far in the attempt to
fixate an object, and which was not a recursive signal from a “motor centre”.
He was joined in this interpretation
by William James (1893) and Edward Titchener (1907), thus delaying deployment
of the concepts of neural feedback in re-entrant cognitive processes until
late in the 20th century.
23. The sensory cortical constructions consist
of brief staccato messages to the limbic system, which convey what is sought
and the result of the search. After
multisensory convergence, the spatiotemporal activity pattern in the limbic
system is up-dated through temporal integration in the hippocampus.
Accompanying sensory messages there
are return up-dates from the limbic system to the sensory cortices, whereby
each cortex receives input that has been integrated with the input from all
others, reflecting the unity of intentionality.
Everything that a human or an animal
knows comes from the circular causality of action, preafference, perception,
and up-date. It is done by successive
frames of self-organized activity patterns in the sensory and limbic cortices.
4.
Level 3: Circular causality among neurons and neural masses
24 The “state” of the brain is a description of
what it is doing in some specified time period.
A phase transition occurs when the
brain changes and does something else. For
example, locomotion is a state, within which walking is a rhythmic pattern of
activity that involves large parts of the brain, spinal cord, muscles and
bones. The entire neuromuscular system
changes almost instantly with the transition to a pattern of jogging or
running. Similarly, a sleeping state
can be taken as a whole, or divided into a sequence of slow wave and REM
stages. Transit to a waking state can
occur in a fraction of a second, whereby the entire brain and body shift
gears, so to speak. The state of a
neuron can be described as active and firing or as silent, with sudden changes
in patterns of firing constituting phase transitions.
Populations of neurons also have a
range of states, such as slow wave, fast activity, seizure, or silence.
The science of dynamics describes
states and their phase transitions.
(a)
Stability
25. The most critical question to ask about a
state is its degree of stability or resistance to change. Stability is
evaluated by perturbing an object or a system (Freeman 1975).
For example, an egg on a flat surface
is unstable, but a coffee mug is stable. A
person standing on a moving bus and holding on to a railing is stable, but
someone walking in the aisle is not. If
a person regains his chosen posture after each perturbation, no matter in
which direction the displacement occurred, that state is regarded as stable,
and it is said to be governed by an attractor.
This is a metaphor to say that the system goes (“is attracted to”) the
state through interim transiency. The
range of displacement from which recovery can occur defines the basin of
attraction, in analogy to a ball rolling to the bottom of a bowl.
If a perturbation is so strong that it
causes concussion or a broken leg, and the person cannot stand up again, then
the system has been placed outside the basin of attraction, and a new state
supervenes with its own attractor and basin of attraction.
26. Stability is always relative to the time
duration of observation and the criteria for what is chosen to be observed.
In the perspective of a lifetime,
brains appear to be highly stable, in their numbers of neurons, their
architectures and major patterns of connection, and in the patterns of
behavior they produce, including the character and identity of the individual
that can be recognized and followed for many years.
A brain undergoes repeated transitions
from waking to sleeping and back again, coming up refreshed with a good night
or irritable with insomnia, but still, giving arguably the same person as the
night before. But in the perspective
of the short term, brains are highly unstable.
Thoughts go fleeting through awareness, and the face and body twitch
with the passing of emotions. Glimpses
of the internal states of neural activity reveal patterns that are more like
hurricanes than the orderly march of symbols in a computer, with the
difference that hurricanes don’t learn. Brain
states and the states of populations of neurons that interact to give brain
function, are highly irregular in spatial form and time course.
They emerge, persist for a small
fraction of a second, then disappear and are replaced by other states.
27. Neuroscientists aim to describe and measure
these states and tell what they mean both to observations of behavior and to
experiences with awareness. We
approach the dynamics by defining three kinds of stable state, each with its
type of attractor. The simplest is the
point attractor. The system is at rest
unless perturbed, and it returns to rest when allowed to do so.
As it relaxes to rest, it has a brief
history, but loses it on convergence to rest.
Examples of point attractors are neurons or neural populations that
have been isolated from the brain, and also the brain that is depressed into
inactivity by injury or a strong anesthetic, to the point where the EEG has
gone flat. A special case of a
point attractor is noise. This state
is observed in populations of neurons in the brain of a subject at rest, with
no evidence of overt behavior or awareness. The
neurons fire continually but not in concert with each other.
Their pulses occur in long trains at
irregular times. Knowledge about
the prior pulse trains from each neuron and those of its neighbors up to the
present fails to support the prediction of when the next pulse will occur.
The state of noise has continual
activity with no history of how it started, and it gives only the expectation
that its average amplitude and other statistical properties will persist
unchanged.
28. A system that gives periodic behavior is
said to have a limit cycle attractor. The
classic example is the clock. When it
is viewed in terms of its ceaseless motion, it is regarded as unstable until
it winds down, runs out of power, and goes to a point attractor.
If it resumes its regular beat after
it is re-set or otherwise perturbed, it is stable as long as its power lasts.
Its history is limited to one cycle,
after which there is no retention of its transient approach in its basin to
its attractor. Neurons and populations
rarely fire periodically, and when they appear to do so, close inspection
shows that the activities are in fact irregular and unpredictable in detail,
and when periodic activity does occur, it is either intentional, as in
rhythmic drumming, or pathological, as in nystagmus and Parkinsonian tremor.
29. The third type of attractor gives aperiodic
oscillation of the kind that is observed in recordings of EEGs and of
physiological tremors. There is no one
or small number of frequencies at which the system oscillates.
The system behavior is therefore
unpredictable, because performance can only be projected far into the future
for periodic behavior. This type was
first called “strange”; it is now widely known as “chaotic”.
The existence of this type of
oscillation was known to mathematicians a century ago, but systematic study
was possible only recently after the full development of digital computers.
The best known simple systems with
chaotic attractors have a small number of components and a few degrees of
freedom, as for example, the double-hinged pendulum, and the dripping faucet.
Large and complex systems such as
neurons and neural populations are thought to be capable of chaotic behavior,
but proof is not yet possible at the present level of developments in
mathematics.
30. The discovery of chaos has profound
implications for the study of brain function (Skarda and Freeman 1987).
A dynamic system has a collection of
attractors, each with its basin, which forms an ‘attractor landscape’ with all
three types. The state of the system
can jump from one to another in an itinerant trajectory (Tsuda 1991).
Capture by a point or limit cycle
attractor wipes clean the history upon asymptotic convergence, but capture in
a chaotic basin engenders continual aperiodic activity, thereby creating
novel, unpredictable patterns that retain its history.
31. Although the trajectory is not predictable,
the statistical properties such as the mean and standard deviation of the
state variables of the system serve as measures of its steady state.
Chaotic fluctuations carry the system
endlessly around in the basin. However,
if energy is fed into the system so that the fluctuations increase in
amplitude, or if the landscape of the system is changed so that the basin
shrinks or flattens, a microscopic fluctuation can carry the trajectory across
the boundary between basins to another attractor.
This crossing constitutes a first
order phase transition.
32. In each sensory cortex there are multiple
chaotic attractors with basins corresponding to previously learned classes of
stimuli, including that for the learned background stimulus configuration,
which constitutes an attractor landscape. This
chaotic prestimulus state of expectancy establishes the sensitivity of the
cortex by warping the landscape, so that a very small number of sensory action
potentials driven by an expected stimulus can carry the cortical trajectory
into the basin of an appropriate attractor. Circular
causality enters in the following way. The
state of a neural population in an area of cortex is a macroscopic event that
arises through the interactions of the microscopic activity of the neurons
comprising the neuropil. The global
state is upwardly generated by the microscopic neurons, and simultaneously the
global state downwardly organizes the activities of the individual neurons.
33. Each cortical phase transition requires this
circularity. It is preceded by a
conjunction of antecedents. A stimulus
is sought by the limbic brain through orientation of the sensory receptors in
sniffing, looking, and listening. The
landscape of the basins of attraction is shaped by limbic preafference, which
facilitates access to an attractor by expanding its basin for the reception of
a desired class of stimuli. Preafference
provides the ambient context by multisensory divergence.
The web of synaptic connections
modified by prior learning maintains the basins and attractors.
Pre-existing chaotic fluctuations are
enhanced by input, forcing the selection of a new macroscopic state that then
engulfs the stimulus-driven microscopic activity.
34. The first proposed reason that all the
sensory systems (visual, auditory, somatic and olfactory) operate this way is
the finite capacity of the brain faced with the infinite complexity of the
environment. In olfaction, for
example, a significant odorant may consist of a few molecules mixed in a rich
and powerful background of undefined substances, and it may be continually
changing in age, temperature, and concentration.
Each sniff in a succession with the
same chemical activates a different subset of equivalent olfactory receptors,
so the microscopic input is unpredictable and unknowable in detail.
Detection and tracking require an
invariant pattern over trials. This is
provided by the attractor, and the generalization over equivalent receptors is
provided by the basin. The attractor
determines the response, not the particular stimulus.
Unlike the view proposed by
stimulus-response reflex determinism, the dynamics gives no linear chain of
cause and effect from stimulus to response that can lead to the necessity of
environmental determinism. The second
proposed reason is the requirement that all sensory patterns have the same
basic form, so that they can be combined into Gestalts, once they are
converged to be integrated over time.
5. Circular causality in
awareness
35. Circular causality, then, occurs with each
phase transition in sensory cortices and the olfactory bulb, when fluctuations
in microscopic activity exceed a certain threshold, such that a new
macroscopic oscillation emerges to force cooperation on the very neurons that
have brought the pattern into being. EEG
measurements show that multiple patterns self-organize independently in
overlapping time frames in the several sensory and limbic cortices, coexisting
with stimulus-driven activity in different areas of the neocortex, which
structurally is an undivided sheet of neuropil in each hemisphere receiving
the projections of sensory pathways in separated areas.
36. Circular causality can serve as the
framework for explaining the operation of awareness in the following way.
The multimodal macroscopic patterns
converge simultaneously into the limbic system, and the results of integration
over time and space are simultaneously returned to all of the sensory systems.
Here I propose that another level of
hierarchy exists in brain function as a hemispheric attractor, for which the
local macroscopic activity patterns are the components.
The forward limb of the circle
provides the bursts of oscillations converging into the limbic system that
destabilize it to form new patterns. The
feedback limb incorporates the limbic and sensory cortical patterns into a
global activity pattern or order parameter that enslaves all of the
components. The enslavement enhances
the coherence among all of them, which dampens the chaotic fluctuation instead
of enhancing it, as the receptor input does in the sensory cortices.
37. A global operator of this kind must exist,
for the following reason. The
synthesis of sense data first into cortical wave packets and then into a
multimodal packet takes time. After a
Gestalt has been achieved through embedding in past experience, a decision is
required as to what the organism is to do next.
This also takes time for an
evolutionary trajectory through a sequence of attractors constituting the
attractor landscape of possible goals and actions (Tsuda, 1991).
The triggering of a phase transition
in the motor system may occur at any time, if the fluctuations in its multiple
inputs are large enough, thereby terminating the search trajectory.
In some emergent behavioral situations
an early response is most effective: action without reflection.
In complex situations with unclear
ramifications into the future, precipitate action may lead to disastrous
consequences. More generally, the
forebrain appears to have developed in phylogenetic evolution as an organ
taking advantage of the time provided by distance receptors for the
interpretation of raw sense data. The
quenching function of a global operator to delay decision and action can be
seen as a necessary complement on the motor side, to prevent premature closure
of the process of constructing and evaluating possible courses of action.
This view is comparable to that of
William James (1879), who wrote: “... the study à posteriori of the
distribution of consciousness shows it to be exactly such as we might expect
in an organ added for the sake of steering a nervous system grown too complex
to regulate itself.”, except that consciousness is not provided by another
“organ” (an add-on part of the human brain) but by a new hierarchical level of
organization of brain dynamics.
38. Action without the deferral that is implicit
in awareness can be found in so-called ‘automatic’ sequences of action in the
performance of familiar complex routines. Actions
‘flow’ without awareness. Implicit
cognition is continuous, and it is simply unmasked in the conditions that lead
to ‘blindsight’. In this view, emotion
is defined as the impetus for action, more specifically, as impending action.
Its degree is proportional to the
amplitude of the chaotic fluctuations in the limbic system, which appears as
the modulation depth of the carrier waves of limbic neural activity patterns.
In accordance with the James-Lange
theory of emotion (James 1893), it is experienced through awareness of the
activation of the autonomic nervous system in preparation for and support of
overt action, as described by Cannon (1939). It
is observed in the patterns of behavior that social animals have acquired
through evolution (
39. Evidence for the existence of the postulated
global operator is found in the high level of covariance in the EEGs
simultaneously recorded from the bulb and the visual, auditory, somatic and
limbic (entorhinal) cortices of animals and from the scalp of humans (Lehmann
and Michel 1990). The magnitude of the
shared activity can be measured in limited circumstances by the largest
component in principle components analysis (PCA).
Even though the wave forms of the
several sites vary independently and unpredictably, the first component has
50-70% of the total variance (Smart et al., 1997; Gaál and Freeman, 1997).
These levels are lower than those
found within each area of 90-98% (Barrie, Freeman and Lenhart, 1996), but they
are far greater than can be accounted for by any of a variety of statistical
artefacts or sources of correlation such as volume conduction, pacemaker
driving, or contamination by the reference lead in monopolar recording.
The high level of coherence holds for
all parts of the EEG spectrum and for aperiodic as well as near-periodic
waves.
40. The maximal coherence appears to have zero
phase lag over distances up to several centimeters between recording sites and
even between hemispheres (Singer and Gray, 1995).
Attempts are being made to model the
observed zero time lag among the structures by cancellation of delays in
bidirectional feedback transmission (König and Schillen, 1991; Traub et al.
1996; Roelfsma et al., 1997).
6.
Consciousness viewed as a system parameter controlling chaos
41 A clear choice can be made now between the
three meanings of causality proposed in the Introduction.
Awareness and neural activity are not
acausal parallel processes, nor does either make or move the other as an
agency in temporal sequence. Circular
causality is a form of explanation that can be applied at several hierarchical
levels without recourse to agency. This
formulation provides the sense or feeling of necessity that is essential for
human comprehension, by addressing the elemental experience of cause and
effect in acts of observation, even though logically it is very different from
linear causality in all aspects of temporal order, spatial contiguity, and
invariant reproducibility. The phrase
is a cognitive metaphor. It lacks
the attribute of agency, unless and until the loop is broken into the forward
(microsocopic) limb and the recurrent (macroscopic) limb, in which case the
agency that is so compelling in linear causality can be re-introduced.
This move acquiesces to the needs of
the human observers to use it in order to comprehend dynamic events and
processes in the world.
42. I propose that the globally coherent
activity, which is an order parameter, may be an objective correlate of
awareness through preafference, comprising expectation and attention, which
are based in prior proprioceptive and exteroceptive feedback of the sensory
consequences of previous actions, after they have undergone limbic integration
to form Gestalts, and in the goals that are emergent in the limbic system.
In this view, awareness is basically
akin to the intervening state variable in a homeostatic mechanism, which is
both a physical quantity, a dynamic operator, and the carrier of influence
from the past into the future that supports the relation between a desired set
point and an existing state. The
content of the awareness operator may be found in the spatial pattern of
amplitude modulation of the shared wave form component, which is comparable to
the amplitude modulation of the carrier waves in the primary sensory receiving
areas.
43. What is most remarkable about this operator
is that it appears to be antithetical to initiating action.
It provides a pervasive neuronal bias
that does not induce phase transitions, but defers them by quenching local
fluctuations (Prigogine, 1980). It
alters the attractor landscapes of the lower order interactive masses of
neurons that it enslaves. In the
dynamicist view, intervention by states of awareness in the process of
consciousness organizes the attractor landscape of the motor systems, prior to
the instant of its next phase transition, the moment of choosing in the limbo
of indecision, when the global dynamic brain activity pattern is increasing
its complexity and fine-tuning the guidance of overt action.
This state of uncertainty and
unreadiness to act may last a fraction of a second, a minute, a week, or a
lifetime. Then when a contemplated act
occurs, awareness follows the onset of the act and does not precede it.
44. In that hesitancy, between the last act and
the next, comes the window of opportunity, when the breaking of symmetry in
the next limbic phase transition will make apparent what has been chosen.
The observer of the self intervenes by
awareness that organizes the attractor landscape, just before the instant of
the next transition:
Between the conception
And the creation
Between the emotion
And the response
Falls the Shadow
Life is very long
T. S. Eliot (1936)
The Hollow Men
The causal technology of self-control is
familiar to everyone: hold off fear and anger; defer closure; avoid
temptation; take time to study; read and reflect on the opportunity, meaning,
and consequences; take the long view as it has been inculcated in the
educational process. According to Mill
(1843): “We cannot, indeed, directly will to be different from what we are;
but neither did those who are supposed to have formed our characters directly
will that we should be what we are. Their
will had no direct power except over their own actions... We are exactly as
capable of making our own character, if we will, as others are of making it
for us” (p. 550).
(b) Current Limitation of
Neurodynamics
45. There are numerous unsolved problems with
this hypothesis. Although strong
advances are being made in analyzing the dynamics of the limbic system and its
centerpieces, the entorhinal cortex and hippocampus (Boeijinga and Lopes da
Silva, 1988; O’Keefe and Nadel, 1978; Rolls et al., 1989; McNaughton, 1993;
Wilson and McNaughton, 1993; Buzsaki, 1996; Eichenbaum, 1997; Traub et al.
1996), their self-organized spatial patterns, their precise intentional
contents and their mechanisms of formation in relation to intentional action
are still unknown. The pyriform cortex
to which the bulb transmits is strongly driven by its input, and it lacks the
phase cones that indicate self-organizing capabilities comparable to those of
the sensory cortices. Whether the
hippocampus has those capabilities or is likewise a driven structure is
unknown. The neural mechanisms by
which the entire neocortical neuropil in each hemisphere maintains spatially
coherent activity over a broad spectrum with nearly zero time lag are unknown.
The significance of this coherent
activity for behavior is dependent on finding correlates with behaviors, but
these are unknown. If those correlates
are meanings, then the subjects must be asked to make representations of the
meanings in order to communicate them, so that they are far removed from overt
behavior. Knowledge of human brain
function is beyond the present reach of neurodynamics because our brains are
too complex, owing to their mechanisms for language and self-awareness.
7. Causality
belongs in technology, not in science
46. The case has now been made on the grounds of
neurodynamics that causality is a form of knowing through intentional action.
Thus causality is inferred not to
exist in material objects, but to be assigned to them by humans with the
intent to predict and control them. The
determinants of human actions include not only genetic and environmental
factors but self-organizing dynamics in brains, primarily operating through
the dynamics of intentional action, and secondarily through neural processes
that support consciousness, which is commonly but mistakenly attached to free
will. While this inference is not new,
it is given new cogency by recent developments in neuroscience.
What, then, might be the consequences
for natural science, philosophy, and medicine, if this inference is accepted?
(a) Limitations of Linear
Causality
47. The concept of causality is fundamental in
all aspects of human behavior and understanding, which includes our efforts in
laboratory experiments and the analysis of data to comprehend the causal
relations of world, brain and mind. In
my own work I studied the impact on brain activity of stimuli that animals
were trained to ignore or to respond to, seeking to determine how the stimuli
might cause new patterns of brain activity to form, and how the new patterns
might shape how the animals behaved in response to the stimuli.
I attempted to interpret my findings
and those of others in terms of chains of cause and effect, which I learned to
identify as ‘linear causality’ (Freeman 1975).
48. These attempts repeatedly foundered in the
complexities of neural activity and in the incompatibility of self-organized,
goal-directed behavior of my animals with behaviorist models based on
input-output determinism. I found that
I was adapting to the animals at least as much as they were being shaped by
me. My resort to acausal correlation
based in multivariate statistical prediction was unsatisfying.
Through my readings in physics and
philosophy I learned the concept of ‘circular causality’, which invokes
hierarchical interactions of immense numbers of semiautonomous elements such
as neurons, which form nonlinear systems. These
exchanges lead to the formation of macroscopic population dynamics that shapes
the patterns of activity of the contributing individuals.
I found this concept to be applicable
at several levels, including the interactions between neurons and neural
masses, between component masses of the forebrain, and between the behaving
animal and its environment, under the rubric of intentionality (Freeman 1995).
(b) Applicability of
Circular Causality
49. By adopting this alternative concept I
changed my perspective (Freeman 1995). I
now sought not to pin events at instants of time, but to conceive of intervals
at differing time scales; not to fill the gaps in the linear chains, but to
construct the feedback pathways from the surround; not to average the single
responses to monotonously repeated stimuli, but to analyze each event in its
uniqueness before generalizing; not to explain events exclusively in terms of
external stimuli and context, but to allow for the contribution of
self-organizing dynamics.
50. Circular causality departs so strongly from
the classical tenets of necessity, invariance, and precise temporal order that
the only reason to call it that is to satisfy the human habitual need for
causes. The most subtle shift is the
disappearance of agency, which is equivalent to loss of Aristotle’s efficient
cause. Agency is a powerful metaphor.
For examples, it is common sense to
assert that an assassin causes a victim’s death; that an undersea quake causes
a tsunami; that a fallen tree causes a power failure by breaking a
transmission line; that an acid-fast bacillus causes tuberculosis; that an
action potential releases transmitter molecules at a synapse; and so forth.
But interactions across hierarchical
levels do not make sense in these terms. Molecules
that cooperate in a hurricane cannot be regarded as the agents that cause the
storm. Neurons cannot be viewed as the
agents that make consciousness by their firing.
51. The very strong appeal of agency to explain
events may come from the subjective experience of cause and effect that
develops early in human life, before the acquisition of language, when as
infants we go through the somatomotor phase (Piaget 1930; Thelen and Smith
1994) and learn to control our limbs and to focus our sensory receptors.
“I act (cause); therefore I feel (effect).”
Granted that causality can be
experienced through the neurodynamics of acquiring knowledge by the use of the
body, the question I raise here is whether brains share this property with
other material objects in the world. The
answer I propose is that assignment of cause and effect to one’s self and to
others having self-awareness is entirely appropriate, but that investing
insensate objects with causation is comparable to investing them with
teleology and soul.
52. The further question is: Does it matter
whether or not causality is assigned to objects?
The answer here is: very much.
Several examples are given of
scientific errors attributable to thinking in terms of linear causality.
The most important, with wide
ramifications, is the assumption of universal determinacy, by which the causes
of human behavior are limited to environmental and genetic factors, and the
causal power of self-determination is excluded from scientific consideration.
We know that linear extrapolation
often fails in a nonlinear world. Proof
of the failure of this inference is by
reductio ad absurdum. It is absurd
in the name of causal doctrine to deny our capacity as humans to make choices
and decisions regarding our own futures, when we exercise the causal power
that we experience as free will.
8.
Anthropocentricity in acts of human observation
53. Our ancestors have a history of interpreting
phenomena in human terms appropriate to the scales and dynamics of our brains
and bodies. An example of our
limitations and our cognitive means for surmounting them is our spatial
conception of the earth as flat. This
belief is still quite valid for lengths of the size of the human body, such as
pool tables, floors, and playing fields, where we use levels, transits, and
gradometers, and even for distances that we can cover by walking and swimming.
The subtleties of ships that were
hull-down over the horizon were mere curiosities, until feats of intellect and
exploration such as circumnavigation of the earth opened a new spatial scale.
Inversely, at microscopic dimensions
of molecules flatness has no meaning. Under
an electron microscope the edge of a razor looks like a mountain range.
54. In respect to time scales, we tend to think
of our neurons and brains as having static anatomies, despite the evidence of
continual change from time lapse cinematography, as well as the cumulative
changes that passing decades reveal to us in our bodies.
An intellectual leap is required to
understand that form and function are both dynamic, differing essentially in
our time scales of measurements and experiences with them.
The embryological and phylogenetic
developments of brains are described by sequences of geometric forms and the
spatiotemporal operations by which each stage emerges from the one preceding.
The time scales are in days and eons,
not in seconds as in behavior and its neurophysiological correlates.
55. The growth of structure and the formation of
the proper internal axonal and dendritic connections is described by fields of
attraction and repulsion, with gradient descents mediated by contact
sensitivities and the diffusion of chemicals.
Moreover, recent research shows that synapses undergo a process of
continual dynamic formation, growth and deletion throughout life (Smythies,
1997). The same and similar terms are
used in mathematics and the physical sciences such as astronomy and cosmology,
over a variety of temporal and spatial scales, many of which are far from the
scales of kinesthesia to which we are accustomed.
On the one hand, morphogenesis is the
geometry of motion, which we can grasp intuitively through time lapse
photography. On the other hand, the
motions of speeding bullets and hummingbird wings are revealed to us by
high-speed cinematography.
(a)
Intentionality as property of material objects
56. The attribution of intention as a property
of material objects was common in earlier times by the assignment of spirits
to trees, rocks, and the earth. An
example is the rising sun. From the
human perspective the sun seems to ascend above the horizon and move across
the sky. In mythology this motion was
assigned to an agency such as a chariot carrying the sun, or to motivation by
the music of Orpheus, because music caused people to dance.
In the Middle Ages the sun, moon,
planets and stars were thought to be carried by spheres that encircled the
earth and gave ineffable music as they rotated.
The current geometric explanation is
that an observer on the earth’s surface shifts across the terminator with
inertial rotation in an acausal space-time relation.
Still, we watch the sun move.
57. Similarly, humans once thought that an
object fell because it desired to be close to the earth, tending to its
natural state. In Newtonian mechanics
it was pulled down by gravity. In
acausal, relativistic terms, it follows a geodesic to a minimal energy state.
The Newtonian view required action at
a distance, which was thought to be mediated by the postulated quintessence
held over from Aristotle, the “ether”. Physicists
were misled by this fiction, which stemmed from the felt need for a medium to
transmit a causal agent. The
experimental proof by Michaelson and Morley that the ether did not exist
opened the path to relativistic physics and an implicit renunciation of
gravitational causality. But
physicists failed to pursue this revolution to its completion, and instead
persisted in the subject-object distinction by appealing to the dependence of
the objective observation on the subjective reference frame of the observer.
(b) Suppression of feedback
mechanisms
58. In complex, multivariate systems interactive
at several levels like brains, causal sequences are virtually impossible to
specify unequivocally. Because it
introduced indeterminacy, evidence for feedback in the nervous system was
deliberately suppressed in the first third of the 20th century.
It was thought that a neuron in a
feedback loop could not distinguish its external input from its own output.
An example was the reaction of Ramón y
Cajal to a 1929 report by his student, Rafael Lorente de Nó, who presented
Cajal with his Golgi study of neurons in the entorhinal cortex (Freeman 1984).
He constructed diagrams of
axodendritic connections among the neurons with arrows to indicate the
direction of transmission, and he deduced that they formed feedback loops.
Cajal told him that his inference was
unacceptable, because brains were deterministic and could not work if they had
feedback. He withdrew his report from
publication until Cajal died in 1934. After
he published it (Lorente de Nó 1934), it became an enduring classic, leading
to the concept of the nerve cell assembly by its influence on Donald Hebb
(1949), and to neural networks and digital computers by inspiring Warren
McCulloch and through him John von Neumann (1958).
The concept of linear causality
similarly slowed recognition and acceptance of processes of self-organization
in complex systems, by the maxim that “nothing can cause itself.”
The phrase “self-determination” was
commonly regarded as an oxymoron. A
similar exclusion delayed acceptance of the concept of reafference, also
called corollary discharge (Freeman 1995).
59. Description of a linear causal connection is
based on appeal to an invariant relationship between two events.
If an effect follows, the cause is
sufficient; if an effect is always preceded by it, then the cause is
necessary. From the temporal order and
its invariance, as attested by double-blind experimental controls to
parcellate the antecedents, an appearance of necessity is derived.
The search concludes with assignment
of an agency, that has responsibility for production, direction, control or
stimulation, and that has its own prior agency, since every cause must also be
an effect.
60. According to David Hume (1739), causation
does not arise in the events; it emerges in the minds of the observers.
The temporal succession and spatial
contiguity of events that are interpreted as causes and effects comprise the
invariant connection. It is the
felt force of conjoined impressions that constitutes the quale of causality.
Since the repetition of these
relations adds no new idea, the feeling of the necessity has to be explained
psychologically. He came to this
conclusion from an abstract premiss in the doctrine of the nominalism,
according to which there are no universal essences in reality, so the mind
cannot frame a concept or image that corresponds to any universal or general
term, such as causality. This was
opposed, then as now, to the doctrine of scientific realism. Hume and his
nominalist colleagues were anticipated 500 years earlier by the work of
Aquinas (1272), who conceived that the individual forms of matter are
abstracted by the imagination (“phantasia”) to create universals that exist
only in the intellect, not in matter. Early
20th century physicists should have completed the Humeian revolution in their
development of quantum mechanics, but they lost their nerve and formulated
instead the
61. Conversely, John Stuart Mill (1873) accepted
“the universal law of causation” but not necessity “... the doctrine of what
is called Philosophical Necessity” weighed on my existence like an incubus...
I pondered painfully on the subject, till gradually I saw light through it.
I perceived, that the word Necessity,
as a name for the doctrine of Cause and Effect applied to human action,
carried with it a misleading association; and that this association was the
operative force in the depressing and paralyzing influence which I had
experienced” (pp. 101-102). He
developed his position fully in “A System of Logic” (1843).
62. Kant (1781) insisted that science could not
exist without causality. Since
causality was for him a category in mind, it follows that science is a body of
knowledge about the world but is not in the world.
Causality then becomes a basis for
agreement among scientists regarding the validation of relationships between
events, and the prediction of actions to be taken for control of events in the
world. Since it could not be validated
by inductive generalization from sense data, but was nevertheless essential to
give wholeness and completion to experience [Apperzeption], Kant concluded
that it must be “a priori” and “transcendental” over the sense data.
This led him to designate causality as
a category [Kategorien] in and of the mind, along with space and time as the
forms of perception [Anschauungsformen], by which the sense data were
irretrievably modified during assembly into perceptions, making the real world
[Ding an sich] inaccessible to direct observation.
63. Friedrich Nietzsche (1886) placed causality
in the mind as the expression of free will: “The question is in the end
whether we really recognize the will as efficient, whether we believe in the
causality of the will: if we do - and at bottom our faith in this is nothing
less than our faith in causality itself - then we have to make the experiment
of positing the causality of the will hypothetically as the only one ... the
will to power” (p. 48).
64. Putnam (1990) assigned causality to the
operation of brains in the process of observation: “Hume’s account of
causation... is anathema to most present-day philosophers.
Nothing could be more contrary to the
spirit of recent philosophical writing than the idea that there is nothing
more to causality than regularity or the idea that, if there is something
more, that something more is largely subjective.” (p. 81)
“If we cannot give a single example of
an ordinary observation report which does not, directly or indirectly,
presuppose causal judgments, then the empirical distinction between the
“regularities” we “observe” and the “causality” we “project onto” the objects
and events involved in the regularities collapses.
Perhaps the notion of causality is so
primitive that the very notion of observation presupposes it?” [p. 75]
65. A case was made by Davidson (1980) for
“anomalous monism” to resolve the apparent contradiction between the
deterministic laws of physics, the necessity for embodiment of mental
processes in materials governed by those fixed laws, and the weakness of the
“laws” governing psychophysical events as distinct from statistical classes of
events: “Why on earth should a cause turn an action into a mere happening and
a person into a helpless victim? Is it
because we tend to assume, at least in the arena of action, that a cause
demands a causer, agency and agent? So
we press the question; if my action is caused, what caused it?
If I did, then there is the absurdity
of an infinite regress; if I did not, I am a victim.
But of course the alternatives are not
exhaustive. Some causes have no
agents. Among these agentless causes
are the states and changes of state in persons which, because they are reasons
as well as causes, constitute certain events free and intentional actions.”
[p. 19]
66. His premisses have been superceded in two
respects. First, he postulated that
brains are material systems, for which the laws of physics support accurate
prediction. He described brains as
“closed systems”. In the past three
decades numerous investigators have realized that brains are open systems, as
are all organs and living systems, with an infinite sink in the venous return
for waste heat and entropy, so that the 1st and 2nd laws of thermodynamics do
not hold for brains, thus negating one of his two main premisses.
Second, he postulated that, with
respect to meaning, minds are “open” systems, on the basis that they are
continually acting into the world and learning about it.
The analyses of electrophysiological
data taken during the operations of sensory cortices during acts of perception
indicate that meaning in each mind is a closed system, and that meaning is
based in chaotic constructions, not in information processing, thus negating
the other of his two main premisses. In
my view, neurons engage in complex biochemical operations that have no meaning
or information in themselves, but inspire meaning in researchers who measure
them. The degree of unpredictability
of mental and behavioral events is in full accord with the extent of
variations in the space-time patterns of the activity of chaotic systems, thus
removing the requirement for the adjective, “anomalous”, because it applies to
both sets of laws for the material and mental aspects of living systems.
Moreover, the adoption of the concept
“circular causality” from physics and psychology removes agency.
That which remains is “dynamical
monism”.
10. Applications
of causality in medical technology
67. Causality is properly attributed to
intentional systems, whose mechanisms of exploring, learning, choosing,
deciding, and acting constitute the actualization of the feeling of necessary
connection, and of the cognitive metaphor of agency.
It is properly used to describe
technological intervention into processes of the material world after analysis
of the interrelations of events. Surmounting
linear causal thinking may enable neuroscientists to pursue studies in the
dynamics of the limbic system to clarify the meanings of statistical
regularities in chaotic, self-organizing systems and change their outcomes by
experimental manipulation. Social
scientists may take advantage of the discovery of a biological basis for
choice and individual responsibility to strengthen our social and legal
institutions by complementing environmental and genetic linear causation.
The nature-nurture debate has
neglected a third of the determinant triad: the self
People can and do make something of
themselves. Neurophilosophers studying
consciousness in brain function may find new answers to old questions by
re-opening the debate on causality. What
acausal relations arise among the still inadequately defined entities
comprising brains? What is the global
operator of consciousness? The
mind-brain problem is not solved, but it can be transplanted to more fertile
ground.
68. My proposal is not to deny or abandon
causality, but to adapt it as an essential aspect of the human mind/brain by
virtue of its attachment to intentionality. This
can be done by using the term “circular causality” divorced from agency in the
sciences, and the term “linear causality” in combination with agency in the
technologies, including medical, social, legal, and engineering applications.
69. For example, medical research is widely
conceived as the search for the causes of diseases and the means for
intervention to prevent or cure them. A
keystone in microbiology is expressed in Koch’s Postulates, which were
formulated in 1881 by Robert Koch to specify the conditions that must be met,
in order to assign a causal relation between a microorganism and a disease:
(1) the germ must always be found in the
disease; (2) it must be isolated in pure culture from the diseased individual;
(3) inoculation with the isolated culture must be followed by the same disease
in a suitable test animal; and (4) the same germ must be isolated in pure
culture from the diseased test animal.
70. These postulates have served well for
understanding transmissible diseases and providing a biological foundation for
developing chemotherapies, vaccines, and other preventatives.
Public health measures addressing
housing, nutrition, waste disposal and water supplies had already been well
advanced in the 19th century for the prevention of pandemics such as cholera,
typhoid, tuberculosis, and dysentery, on the basis of associations and to a
considerable extent the maxim, “Cleanliness is next to Godliness”.
This was intentional behavior of a
high order indeed. The new science
brought an unequivocal set of targets for research on methods of prevention
and treatment.
71. The most dramatic development in
neuropsychiatry was the finding of spirochetes in the brains of patients with
general paresis, for which the assigned causes had been life styles of
dissolution and moral turpitude. The
discovery of the “magic bullet” 606 (arsphenamine) established the medical
model for management of neuropsychiatric illness, which was rapidly extended
to viruses (rabies, polio, measles), environmental toxins (lead, mercury,
ergot), vitamin and mineral deficiencies (cretinism, pellagra), hormonal
deficits (hypothyroidism, diabetic coma, lack of dopamine in postencephalitic
and other types of Parkinson’s disease), and genetic abnormalities (phenylketonuria,
Tourette’s and Huntingdon’s chorea). Massive
research programs are under way to find the unitary causes and the magic
bullets of chemotherapies, replacement genes, and vaccines for Alzheimer’s,
neuroses, psychoses, and schizophrenias. The
current explanations of the affective disorders - too much or too little
dopamine, serotonin, etc. - resemble the Hippocratic doctrine of the four
humors, imbalances of which were seen as the causes of diseases.
72. There are compelling examples of necessary
connections. Who can doubt that the
vibrio causes cholera, or that a now eradicated virus caused small pox?
However, these examples come from
medical technology, in which several specific conditions hold.
First, the discoveries in bacteriology
came through an extension of human perception through the microscope to a new
spatial scale. This led to the
development by Rudolf Virchow of the cellular basis of human pathology.
The bacterial adversaries were then
seen as having the same spatial dimensions as the cells with which they were
at war. The bacterial invaders and the
varieties of their modes of attack did not qualitatively differ from the
macroscopic predators with which mankind had always been familiar, such as
wolves and crocodiles, which humans eradicate, avoid, or maintain in
laboratories and zoos. Second, the
causal metaphor motivated the application of controlled experiments to the
isolation and analysis of target bacterial and viral species, vitamins, toxic
chemicals, hormones, and genes. It
still does motivate researchers, with the peculiar potency of intermittent
reinforcement by occasional success. The
latest example is the recognition that pyloric ulcers are caused by a bacillus
and not by psychic stress or a deleterious life style, implying that the cause
is “real” and not just “psychosomatic”. Third,
the research and therapies are directly addressed to humans, who take action
by ingesting drugs and seeking vaccinations, and who perceive changes in their
bodies thereafter. A feeling of causal
efficacy is very powerful in these circumstances, and many patients commit
themselves without reservation to treatments, well after FDA scientists by
controlled studies have shown them to be ineffective.
The urgency of conceptualizing
causality to motivate beneficial human actions does not thereby establish the
validity of that agency among the objects under study.
Feeling is believing, but it is not
knowing. The feeling of causal agency
in medicine has led to victories, but also to mistakes with injury and death
on a grand scale.
73. Koch’s postulates approach a necessary
connection of a bacillus to an infectious disease, but not the sufficient
conditions. Pathogens are found in
healthy individuals as well, and often not in the sick.
Inoculation does not always succeed in
producing the disease. These anomalies
can be, and commonly are, ignored, if the preponderance of evidence justifies
doing so, but the classical criteria for causality are violated, or are
replaced with statistical judgments. A
positive culture of a bacillus is sufficient reason to initiate treatment with
an antibiotic, even if it is the wrong disease.
Similarly, pathologists cannot tell
the cause of death from their findings at autopsy.
They are trained to state what the
patient died “with” and not “of”. It
is the job of the coroner or a licensed physician to assign the cause of
death. The causes of death are not
scientific. They are social and
technological, and they concern public health, economic well being, and the
apprehension of criminals.
74. Another example of the social value of
causality is the statement: “Smoking causes cancer.”
This is a clear and valid warning that
a particular form of behavior is likely to end in early and painful death.
On the one hand, society has a
legitimate interest in maintaining health and reducing monetary and emotional
costs by investing the strong statistical connection with the motivating
status of causality. On the other
hand, the “causal chain” by which tobacco tars are connected to the unbridled
proliferation of pulmonary epithelial tissue is still being explored, and a
continuing weakness of evidence for the complete linear causal chain is being
used by tobacco companies to claim that there is no proof that smoking causes
cancer. Thus the causal argument has
been turned against society’s justifiable efforts to prevent tobacco-related
illnesses.
11. The Technology of Mental
Illness
76. The most complex and ambiguous field of
medicine concerns the causes and treatments of mental disorders.
Diagnosis and treatment for the past
century have been polarized between the medical model of the causes of
diseases, currently held in biological psychiatry, and psychoanalysis, the
talking cure. Sigmund Freud was
impressed with the phenomena of hysteria, in which patients suffered transient
disabilities, such as blindness and paralysis, but presented no evidence of
infection or anatomical degeneration in their brains.
He drew on his background in clinical
neurology to develop a biological hypothesis (1895) for behavior, based on the
flow of nerve energy between neurons through “contact barriers” (3 years later
named synapses by Foster and Sherrington). Some
axonal pathways developed excessive resistance at these barriers, deflecting
nerve energy into unusual channels by “neuronic inertia”, giving rise to
hysterical symptoms. Within a decade
he had abandoned the biological approach as “premature”, working instead with
his symbolic model of the id, ego, and superego, but his ideas were
generalized to distinguish “functional” from “organic” diseases.
Traumatic childhood experiences warped
the development of the contact barriers. Treatment
was to explore the recesses of memory, bring the resistances to awareness, and
reduce them by client and therapist reasoning together following transference
and countertransference.
77. The bipolarization between the organic and
the functional has been stable for a century.
Patients and practitioners have been able to choose their positions in
this spectrum of causes according to their beliefs and preferences.
Some patients are delighted to be
informed that their disorders are due to chemical imbalances, that are
correctable by drugs and are not their fault or responsibility.
Others bitterly resent the perceived
betrayal by their bodies, and they seek healing through the exercise of mental
discipline and the power of positive thinking.
But the balance has become unstable with two new circumstances.
One is the cost of medical care.
Health maintenance organizations are
pressuring psychiatrists to see more patients in shorter visits, to dispense
with oral histories and the meanings of symptoms for the patients, and to get
them quickly out the door with packets of pills.
The power of biological causality is
clearly in operation as a social, not a scientific, impetus, operating to the
detriment of people with complex histories and concerns.
78. The other circumstance is the growing
realization among mental health care specialists that chemical imbalances,
poor genes, and unfortunate experiences of individuals are insufficient
explanations to provide the foundations for treatment.
Of particular importance for onset,
course, and resolution of illnesses are the social relations of individuals,
their families, neighborhoods, religious communities, and milieu of national
policies and events. Current conflicts
rage over the assignment of the cause of chronic fatigue syndrome to
neuroticism or to a virus; of the Gulf War syndrome to malingering or a
neurotoxin; of post-traumatic stress disorder to battle fatigue or a character
deficit. The dependence of the debates
on causality is fueled by technological questions of human action: what
research is to be done, what treatments are to be given, and who is to pay for
them? Successful outcomes are known to
depend less on pills and counseling than on mobilization of community support
for distressed individuals (Frankl, 1973). These
exceedingly complex relations, involving faith and meaning among family and
friends, may be seriously violated by reduction to unidirectional causes.
Patients may be restored to perfect
chemical balance and then die anyway in despair.
Families may disintegrate into endless
recrimination and self-justification, from lack of tolerance of misdirected
parental and filial intentions and honest mistakes.
So it is with patient-doctor
relations. To seek and find a cause is
to lay the blame, opening the legal right to sue for compensation for
psychological injury and distress. These,
too, are legacies of linear causal thinking.
79. Abnormal behavior in states of trance or
seizure was attributed in past centuries to the loss or willing surrender of
self-control to possession by exotic spirits.
In the West the failure of responsibility was codified as legal
insanity in 1846 according to the McNaughton Rule: “[To] establish a defense
on the grounds of insanity, it must be clearly proven that at the time of the
committing of the act, the party accused was labouring under such a defect of
reason, from disease of the mind, as not to know the nature and quality of the
act he was doing, or, if he did know it, that he did not know he was doing
what was wrong.” In the terms of the
present analysis, for behavior to be insane the neural components of the
limbic system must have entered into basins of attraction that are
sufficiently strange or unusually stable to escape control by the global state
variable. This view encompasses the
two facets of causality, microscopic and macroscopic, that compete for control
of the self, but it is not an adequate statement of the problem.
In fact the case on which the Rule was
based was decided on political grounds (Moran 1981).
Daniel McNaughton was a Scotsman
engaged in ideal-driven assassination, and his transfer by the British
authorities from Newgate Prison to
12. The
science versus the technology of self-control
80. The role of causality in self-awareness is
close to the essence of what it is to be human.
Nowhere is this more poignant than in
the feeling of the need for self-control. Materialists
and psychoanalysts see the limbic self as a machine driven by metabolic needs
and inherited instincts, the id, that carries the ego as a rational critic
that struggles to maintain causal control, as befits the Cartesian metaphor of
the soul serving as the pilot of a boat, by adjudicating blind forces.
Structure and chemistry are
genetically determined. Behaviorist
psychologists confuse motivation with intention and view behavior as the sum
of reflexes, caused by environmental inputs and sociobiological processes,
while consciousness is epiphenomenal.
81. Functionalists see the mind as equivalent to
software that can be adapted to run on any platform, once the algorithms and
rules have been discovered. Logical
operations on symbols as representations are the causes of rational behavior,
and the unsolved problems for research concern the linkage of the symbols with
activities of neurons and with whatever the symbols represent in the world.
That research will be unnecessary, if
the linkages can be made instead to the components of intelligent machines
resembling computers (Fodor 1981). Unfortunately
the only existing intelligent beings have evolved from lower species, and our
brains contain the limbic system as irrational baggage.
Outputs from the logic circuits in the
neocortex, before reaching the motor apparatus, are filtered through the
limbic system, where emotions are attached that distort and degrade the
rational output. Consciousness is a
mystery to be explained by ‘new laws of physics’ (Penrose 1994; Chalmers
1996).
82. Existentialists hold that humans choose what
they become by their own actions.
The cause of behavior is the self, which is here described as emerging through
the dynamics in the limbic system. The
ego constituting awareness of the self discovers its own nature by observing
and analyzing its actions and creations, but cannot claim credit for them.
In extreme claims advanced by
Nietzsche and Sartre the ego is unconstrained by reality.
In more modest terms, because of the
circularity of the relation of the self and its awareness, the future actions
of the self are shaped in the context of its irrevocable past, its body, its
given cultural and physical environment, and its present state of awareness,
which is its own creation. The finite
brain grapples with the infinity of the world and the uncertainty of the
interlocked futures of world and brain, by continually seeking the invariances
that will support reliable predictions. Those
predictions exist as awareness of future possibilities, without which the self
cannot prevail. They are expressed in
the feeling of hope: the future need not merely happen; to some extent it can
be caused.
83. The interactions between microscopic and
macroscopic domains lie at the heart of self-organization.
How do all those neurons
simultaneously get together in a virtual instant, and switch from one
harmonious pattern to another in an orderly dance, like the shuttle of lights
on the “magic loom” of Sherrington (1940)? The
same problem holds for the excitation of atoms in a laser, leading to the
emergence of coherent light from the organization of the whole mass; for the
coordinated motions of molecules of water and air in a hurricane; for the
orchestration of the organelles of caterpillars in metamorphosing to
butterflies; and for the inflammatory spread of behavioral fads, rebellions,
and revolutions that sweep entire nations. All
these kinds of events call for new laws such as those developed in physics by
Haken (1983), in chemistry by Prigogine (1980), in biology by Eigen and
Schuster (1979), in sociology by Foucault (1976), and in neurobiology by
Edelman (1987), which can address new levels of complexity that have
heretofore been inaccessible to human comprehension.
Perhaps these will serve as the “new
laws” called for by Penrose (1994) and Chalmers (1996), but they need not lead
to dualism or panpsychism. They can
arise as logical extensions from the bases of understanding we already have in
these several realms of science, none of which can be fully reduced to the
others.
84. Consciousness in the neurodynamic view is a
global internal state variable composed of a sequence of momentary states of
awareness. Its regulatory role is
comparable to that of the operator in a thermostat, that instantiates the
difference between the sensed temperature and a set point, and that initiates
corrective action by turning a heater on or off.
The machine state variable has little
history and no capacities for learning or determining its own set point, but
the principle is the same: the internal state is a form of energy, an
operator, a predictor of the future, and a carrier of information that is
available to the system as a whole. It
is a prototype, an evolutionary precursor, not to be confused with awareness,
any more than tropism in plants and bacteria is to be confused with
intentionality. In humans, the
operations and informational contents of the global state variable, which are
sensations, images, feelings, thoughts and beliefs, constitute the experience
of causation.
85. To deny this comparability and assert that
humans are not machines is to miss the point.
Two things distinguish humans from all other beings.
One is the form and function of the
human body, including the brain, which has been given to us by three billion
years of biological evolution. The
other is the heritage given to us by two million years of cultural evolution.
Our mental attributes have been
characterized for millennia as the soul or spirit or consciousness that makes
us not-machines. The uniqueness of the
human condition is not thereby explained, but the concept of circular
causality provides a tool for intervention, when something has gone wrong,
because the circle can be broken into forward and feedback limbs.
Each of them can be explained by
linear causality, which tells us where and how to intervene.
The only error would be to assign
causal agency to the parts of the machine.
86. Science provides knowledge of relations
among objects in the world, whereas technology provides tools for intervention
into the relations by humans with intent to control the objects.
The acausal science of understanding
the self distinctively differs from the causal technology of self-control.
“Circular causality” in
self-organizing systems is a concept that is useful to describe interactions
between microscopic neurons in assemblies and the macroscopic emergent state
variable that organizes them. In this
review intentional action is ascribed to the activities of the subsystems.
Awareness (fleeting frames) and
consciousness (continual operator) are ascribed to a hemisphere-wide order
parameter constituting a global brain state. Linear
causal inference is appropriate and essential for planning and interpreting
human actions and personal relations, but it can be misleading when it is
applied to microscopic-microscopic relations in brains.
It is paradoxical to assign linear
causality to brains, and thereby cast doubt on the validity of causal agency
(free will) in choices in and by humans, just because they are materialized in
phase transitions in their brains.
This research was supported by grants from the
National Institutes of Health MH-06686 and the Office of Naval Research
N00014-93-1-0938
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