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(Edited Version)
by T. F. Collura
December 10, 1999
This essay outlines some general issues and
introduces some specific considerations relevant to
the scientific understanding of the mind and brain.
It is intended to elevate critical issues with
regard to the current state of this understanding,
and to define some simple concepts that may help to
move this understanding forward. This work is based
on a synthesis of ideas derived from neuroscience
and psychophysiology, combined with a novel approach
to the understanding of the electroencephalogram
(EEG). These ideas are presented in a very basic
form, and should lead to specific approaches to the
measurement and analysis of brain processes as
revealed by the EEG. It should also lead to the
development and improvement of methods for the
diagnosis and treatment of mental conditions using
EEG and neurofeedback, in conjunction with various
forms of sensory stimulation.
What is needed is a scientific development that
accomplishes for the mind what chemistry has done
for the physical world. That is, a science that
includes simple, terse models for the underpinnings
of thought, and that can be used to derive the
experiences of thought, both behavioral and
introspective. The field that we call Psychology
barely approaches this goal. It has a moderate
ability to connect with our understanding of the
physical brain, but it lacks rigorous and complete
models that are based on neurophysiological
principles. While we have the beginnings of some of
this science, we do not have anything near what has
been achieved in the physical sciences. There is
little agreement on anything approaching a cohesive
model of the substrates of conscious thought. The
clinical effectiveness of conventional methods in
psychology and psychiatry border on chance, further
indicating that this field is still in the stage of
being alchemy rather than science. In particular,
our ability to apply EEG recordings and methods to
the study and development of the mind is in its
infancy.
We have demonstrated the fundamental possibility of
affecting the structure and function of the brain
using biofeedback techniques, and even simple
methods may be as effective as medication in
treating a wide range of conditions. This
underscores the remarkable plasticity of the brain,
and its ability to learn. We may anticipate further
conceptual breakthroughs in the near future that
could revolutionize both our understanding and our
ability to address the issues of the mind and brain
in a constructive manner. It is hoped that this will
help to sweep away much of the imprecision, bias,
and parochialism that currently dominate theoretical
and clinical approaches to the mind.
Whereas we are very good at describing the world
around us, we are very poor at describing the world
of our thoughts. Tibetan Buddhists are perhaps the
masters of this. Nonetheless, we should look to
create a vocabulary and set of paradigms that
penetrates the layers beneath what we commonly think
of as thought. To extend the analogy with the
physical world, we have had our "biology of thought"
defined. Freud, Jung, James, and others have been
our Lamarke, Darwin, Linneaus, and Mendel. What we
need now are the Pauling, the Watson and Crick, and
the Krebs to take us the next level down. We know
what the "organisms" of thought are. They are the
ideas, thoughts, impressions, perceptions, opinions,
moods, and other major entities that are the realm
of psychology. What we know of them we know from
behavioral studies, and a first level of
introspection. What they are comprised of, we do not
know. That is what we are looking for. What are the
"organs" and "molecules" of thought? How does the
brain produce them? What is their "molecular
biology"? From the work of Damasio, Calvin, Crick,
Freeman, Edelman, and others, we have some
rudimentary, basic concepts about brain dynamics
relative to thought. We know that the brain contains
neural subsystems that receive trains of
stimulation, and that reverberate in a complex way,
in accordance with the laws of nonlinear chaos, to
achieve states and state transitions that lead to
recognition, memory, and other primitive processes.
What we would like to do is to find a connection
with the EEG signal in a way that explains what we
know about EEG dynamics in connection with moods,
states of mind, and behavior. This connection should
also have bearing on the observed effects of light
and sound stimulation, which can cause a variety of
affective states, depending on the frequency and
structure of the stimulation. Our basic model is
this: The response of a given cortical sub-circuit
to an incoming burst of stimulation (whether from
the outside world or from a lower brain center)
produces what we will call (for now) a "process
burst". This burst is a short (250-300 millisecond)
pattern of reverberation that is determined by the
resonant properties of the sub-circuit. Although we
only see a simple burst of EEG activity, we know
that there is a complex pattern of information
processing underlying the burst. It is the
underlying processing that we wish to understand. It
is as if we have a scale, a thermometer, and a
barometer, and we wish to begin to develop the
science of chemistry. Instead, we have an EEG
instrument, some lights, sounds, and the
introspective and behavioral reports from our
subject.
THE
BRAIN TAKES IN EXPERIENCE IN CHUNKS. WE CALL THEM
"PROCESS BURSTS"
CHUNKS COME IN RAW, COOKED, AND STALE.
The "process burst" takes in the "experience" that
feeds it, and it has a life of its own. It is
initially "raw", being only aware that something has
happened. Shortly later, it "ripens", and contains
information regarding the details of the input.
Still later, it relaxes, and "chews on" the data,
and reaches a stable plateau of "understanding".
Still later, it introspects, ponders the
information, produces intuitive and deeper
interpretation. Finally, it dies away. The "process
burst" is like a bubble that starts out small,
grows, pauses, grows some more, and finally
disappears either by bursting or by collapsing.
These bursts occur in parallel. There may be
thousands of them at once, in different parts of the
brain, processing different types of information,
different modalities, different views. They are also
coordinated by cross- communication with each other,
using combinations of feedback, feed-forward, and
collateral connections. This provides the
spatio-temporal binding that fuses thousands of
responses into the cohesive experiences that we
interpret as perception, conscious awareness, and
the sense of identity.
CHUNKS OF REALITY CAN BE HOMEMADE OR CAN COME OUT OF
A BOX.
Amidst the cacophony of signals recorded in the EEG,
we can see these bursts coming and going. The key to
the brain's function is in processing these bursts
in trains, one after another. The intrinsic EEG is
built of these bursts as produced by lower brain
centers creating rhythms via the reticular
formation, ascending brain tracts, and thalamus, as
well as intracortical reverberatory activity. The
EEG waves produced by light and sound stimulation
are of course temporally and causally related to the
incoming trains of stimulation. In fact, these
bursts are in this case what we call "evoked
potentials", and that have been studied for many
years, albeit with limited insight and few
conceptual breakthroughs. The common ground in both
is that process bursts are produced at a certain
rate. When a neural sub-circuit in mid-burst is hit
with another incoming stimulus, the burst that is in
progress is interrupted, and the sub-circuit now
begins processing, using the state that was produced
by the preceding burst. This is why the rate at
which the bursts are produced is important. We can
think of the next stimulus as "opening" or
"cracking" the existing burst. It "probes" the
neural sub-circuit by stimulating it when it is in
the state produced by the previous burst. This state
can be the state of being in a "raw" burst, a
"cooked" burst, a "stale" burst or, if long enough,
no burst. These bursts are the "chunks" of
experience that the brain uses to create reality. By
using these bursts as stepping stones on a vast pool
of possible thoughts, the brain navigates its way on
the sea of mind, and thus goes where it will go,
based on the progress from one stone to the next.
YOU
FEED ON THE CHUNKS OF REALITY THAT YOU CREATE.
If
bursts are produced at a certain rate, then the
progress of brain states will take a certain path.
For example, if the bursts are processed at the
"alpha" rate, 10 per second, then successive bursts
are produced while the sub-circuits are in a relaxed
state, hence each burst finds itself built upon a
relaxed sub-circuit. The relaxed state of the brain
is thus created and reinforced. This also explains
why 10 Hz stimulation is relaxing. It in essence
"puts" the brain from stone to stone, as though the
brain were a marionette on strings, and were being
walked along by guidance. Now if the bursts are
produced at a very slow rate, say 5 per second, then
each new burst is built upon a sub-circuit that is
in a deeper, introspective state. This can lead to
an intuitive state of mind, but it can also lead to
a distracted, under stimulated one.
L/S
STIMULATION PRIMES THE PUMP, GIVING YOU A TASTE OF
ANOTHER REALITY
What happens with photic stimulation is that you
give the brain practice with creating and "opening
up" the bursts at a given rate. It is like training
wheels, or pushing a child along on his bicycle. The
brain gets to experience it. It is spoon feeding the
cortex with the experience of processing information
in a certain way, without the brain having to
produce the rhythms on its own. This also explains
why external stimulation can produce a temporary
effect, but generally little learning. The cortex
gets to experience the state produced by the burst
processing, but it has not learned how to keep that
state going. It has not learned to produce the
rhythm on its own. Light/sound stimulation can be
fun, invigorating, deepening, tiring, or even
agitating. What it is doing is force-feeding your
cortex with bursts, and then forcing you to process
the trains at a given rate. You get to practice
processing information at a certain pace, but you
have not learned to pace yourself using internal
mechanisms. This is why auditory or visual
stimulation cannot replace EEG neurofeedback. EEG
neurofeedback rewards the brain for producing (or
not producing) a given rhythm. It rewards the brain
for producing (or inhibiting) the driving
stimulation at the desired rate. This is in addition
to allowing the brain to learn the experience of
processing the bursts at the given rate.
Ultimately, these bursts are taken in a very long
sequence. After thousands and thousands of such
stepping stones, the brain learns to find its
steady-state points. These points may be locations
of alertness, focus, distractedness, agitation,
depression, joy, whatever. The brain tends to
recover and find its equilibrium, which is
presumably some state of rest or relaxation. But
processing information and "lifting" itself out of
the equilibrium point, the brain uses energy to
reach a more excited state. This is what the bursts
do. They "push" the brain into a higher state. Where
that state is, and what its attributes are, depend
on the trajectories of the processing of each burst.
It is hoped that these considerations may motivate
methods that combine auditory and visual stimulation
with EEG, to produce useful and objectively designed
protocols for training the individual.
Copyright 1996, 1997, 1998, 1999, 2000,
2001.2002, 2003, 2004, 2005 Thomas F. Collura,
Ph.D., P.E. All Rights Reserved.
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