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The Center of the Universe
William S. Moxley
5. Neuromechanics The Minefield
PROPOSING A REASONABLE NEUROLOGICAL MODEL for
the operation of the habit routine search process is not the
first minefield that I have had to navigate. Back in the U.S.A.
it seemed a straightforward thing to continue the research which
so few seemed to have the motivation for; several people had
offered varying degrees of support for such projects, but as I
mentioned previously, motivations are a funny thing. My own
seemed at the time to be relatively uncomplicated, and in
retrospect, although I may tend to tidy up my autobiographical
act with a few convenient omissions and over-telling of some of
the high points, je ne regrette rien.
Coincidences, mysteries, personal lessons, and
strange experiences of the most diverse character, as significant
and soul-searching as the Mexican earthquake experience,
continued with a very suspicious frequency. I have previously
mentioned my ability to bear up under the influence of any drug
or shamanic potion, and I sometimes found this ability of even
greater value in dealing with the people and day-to-day events
playing a part in the unfolding of my work. The idea that the
shaman himself must deal with forces and destinies on a far more
fundamental level than the members of his tribe is, of course,
the very spirit and tradition of shamanism. If powerful
psychedelic experiences were to benefit members of the tribe, the
shaman must have already explored the same territory, and gone
well beyond to the very limits of his abilities. In the present
case where the shaman not only administers the powerful
medicines, but actually creates them with the tools of modern
science, his knowledge and intentions are perhaps even more
important.
Thus, in the case of what turned out in some
ways to be a rather successful collaboration between myself and a
trio of avowedly enthusiastic partners, the passage of time and
the achievement of some degree of success seemed to distort the
relations between us in a way very reminiscent of a kind of
vicious parody of the psychedelic experience itself. Meetings and
discussions of plans and goals at first were nothing less than
inspiring. Between us we had the connections and ability to
obtain the necessary raw materials, manufacture a high-quality
product, and distribute it in such a way that it would reach the
right people.
We certainly did not advocate or intend any sort
of mass distribution of psychedelics resulting in their misuse or
ignorant use, which would only call attention to a situation
easily besmirched by adverse publicity. Sensational,
fear-mongering publicity had already made it much more difficult
to properly initiate or introduce a newcomer to the psychedelic
experience. There was certainly a case to be made that many
negative experiences were a direct result of the adverse
publicity itself, for in the early, pre-publicity days of
psychedelic research, "bad trips" were a rarity, even
among alcoholics and psychiatric patients. With normal research
volunteers, the statistics noted by the many researchers
indicated the astonishing safety of psychedelic drugs, not
risk. Now the publicity made it seem that, although an Aldous
Huxley or Alan Watts might get through a psychedelic experience
unscathed, the normal member of society should realize that the
potential risk was overwhelming. And this kind of official
attitude weighed heavily on the person interested to undergo an
experience: even if such a view could in principle be seen for
the hysterical, prohibitionist, puritanical mindset that it in
reality was, the slightest lingering doubt had the possibility to
poison a person's trust in himself and his shaman.
It is perhaps easier to see demons where there
are none to be found. And if demons are encountered, the
idea that they are exterior, real, and caused by something
other than oneself is certainly not conducive to understanding
their meaning. As the Habit Routine Suspension model
demonstrates, the psychedelic experience is no roll of
science-fiction film projected upon consciousness from the
outside. If demons are encountered, they are in reality our
everyday friends seen without the normal range of categorizations
which render them ordinary and insignificant.
The demons which appeared to disrupt our
successful enterprise were therefore more real than those of the
imagination. I can only suspect a hidden agenda on the part of my
co-workers, but the nature of their intentions at the end was so
at odds with the honest enthusiasm of the beginning that I
suspect that the hidden motivations must have developed over
time. From the original enthusiasm there seemed finally to have
evolved a plan to demonstrate once and for all that the
psychedelic experience was, in fact, illegitimate, or at least
unnecessary, its insights illusory, its history merely primitive
self-delusion. To arrive at the establishment reactionary
position through first having professed a more universal and
enlightened view seemed to me altogether impossible. This demon was
real. And what was I going to do about it?
The final scene was quite surreal. The night
before, one of my partners presented me with a five-hundred
dollar banknote, subtly making sure that I noticed the portrait
on the face of the bill, that of the "assassinated
leader", William McKinley, twenty-fifth president of the
United States. At most, I felt only the slightest premonition of
the events the next day would bring, for which we were planning a
day of skiing, and restaurant to follow. Whether the banknote,
and perhaps other similar but unrecognized intimations were
apparent I do not remember, but in the morning I decided to take
a small dose of LSD, to appreciate a day in the high snowy
mountains from a different perspective. In retrospect, I find
that I instinctively tended to undergo a psychedelic experience
at points in my life where a certain crossroads was about to be
reached, when perhaps only vaguely realized intimations of
important changes to come had appeared. Without fail, the
experience would precipitate whatever it was that was pending,
and ignite the insight and decision that would usher in a new
direction.
My friends were newcomers to skiing, and I had
promised to help them get their sea-legs, so to speak. Upon
arriving, I sent them off to the rental shop to secure their
equipment, and I took a test-run on the nearest slope. It was
exhilarating! Although there was quite a crowd that day, the
scene was magnificent. Arriving at base, my friends had not yet
reappeared, so I continued on up again to the irresistible
heights. The next time down the crowd was getting thick enough to
make locating my friends problematic, and in my present state of
exhilaration I couldn't begin to devise a sure-fire method for
finding them. I had to assume that, although our original plan
seemed to be going astray, they would nevertheless have suited up
and found some incidental help with their first few glides on
skis. After a few more runs I began to feel, in contrast to my
exhilaration, a gnawing guilt that I had ignored my friends, even
if through a concurrence of events which I could not have
foreseen. The LSD experience, despite the very modest dose that I
had taken, was attaining a peak more spectacular (in more ways
than one) than those amongst which I was gliding.
Suddenly my friends appeared, and I knew that my
neglect had ruined their day. But the intensity of my feelings,
and their reaction as well, seemed all out of proportion to the
reality of the situation. There was far more significance afoot
than a simple evaluation of the day's events would warrant. My
apologies, and their subdued yet somehow exaggerated insistence
that it didn't really matter, were a mere facade for the emotion
that was all too evident in just a glance. Somehow aspects of the
entire relationship in our joint involvement in the psychedelic
project were metaphorically represented here, and they were
threatening a tumultuous final act upon the stage whose players
had to date seemed so reassuringly without calculation or
subterfuge.
The situation while driving back continued to
intensify. I began to see through the cracks in reality, the
physical manifestations of which became more and more a flimsy
veil affording less and less protection against immediate
dissolution into the hidden dimensions beyond. If my friends were
worried about my driving on the slippery roads, I think that they
too must have sensed, more importantly, that loyalties and
intentions concerning our collective enterprise was the real
issue that was coming to a head. At the restaurant, under the
influence of good food and wine and associated conversation, the
electricity subsided somewhat, and it seemed that things might be
patched up with a resulting return to a situation that we all now
realized had more of deception than honesty. If we could return
to business as usual, we all now knew that on a more fundamental
level, all was changed. This is not, and never has been, a
situation from which effective shamanism can work its benefits to
the full.
Later at their house, in front of a warm
log-fire, I continued to ponder on this last point. So far,
absolutely nothing explicit had actually been discussed
concerning the impending crisis that we each knew to be imminent.
An outsider could not have detected that anything more than the
superficial was transpiring, yet in each others' presence, a mere
glance was like a trumpet fanfare announcing major discoveries
about a hidden side of our co-involvement. It must have been past
midnight when in walked partner number three, whom I had seen
only a few times. He lived quite far away, and I was surprised to
see him at this late hour, but the others apparently had expected
his arrival. After some lengthy and private discussion in the
kitchen, they reappeared, and, very tentatively at first, began
to suggest to me a most surprising plan.
I had recently been working on some advanced
techniques for making our product in a more purified form, and
had been meditating about my experiments probably as a way to
suspend thinking about the more serious implications of the day's
events. At my partners' first mention of LSD I immediately
launched into an attempted discussion of my recent experiments,
perhaps also hoping to repair the situation: At every stage of my
work it was of primary importance to me to be able to continue,
even if this involved having people associated with the project
who neither knew nor cared about the larger implications. If a
partner was interested in nothing but the cash-flow, for example,
I tried to cope with the deficit temporarily until something
better presented itself.
But something was seriously wrong here. One of
my partners was now saying to me that he didn't like the effect
of LSD, it seemed dirty to him, made him sick rather than giving
him inspiration. Despite the day's events and the suspicions that
had been aroused I was quite shocked, and speechless. Gradually
the hidden agenda was presented: what I was to do, was to prepare
a large batch of placebos. Make up what I would say was a batch
of the purest LSD that had ever been made, give them away free to
all my contacts for distribution, and pass along the message that
everyone was to wait until the vernal equinox, then take the new
psychedelic together. The trick was, they would be entirely
inactive, blank doses with nothing but an implied message from...
Yes, from whom? Who was the author of this message? Was this idea
a brainstorm of my partners, suddenly having seen a vision that
drugs were the tools of the devil? The apparent honesty of our
relationship so far in contrast to the way that the plan was
presented, and the things that were said that night, including
the implied threats (the McKinley banknote was burning in my
pocket), and also the implied promises of new and greater
projects and responsibilities for me if I could only see the
wisdom of this plan, made it plain to me that the tiger I had by
the tail was rather larger than I had heretofore suspected.
Well, the activation of my consciousness by the
dose I had taken, and these astounding changes of identity made
manifest that day, made the indoctrination as effective as a
lengthy torture and brainwash session in North Korea. I quite
forced myself to believe the idea had some merit, and for the
next few days, more than half-heartedly prepared a large batch of
chocolate covered placebos in line with the master plan. The
chocolate coating was to prevent anyone examining the underlying
substrate and possibly suspecting that there was less than meets
the eye about this plan for a glorious first-day-of-spring
celebration.
I carried through with the lie to the bitter
end, I don't think there were any suspicions, and I myself
boarded a train for the Grand Canyon to be (1)out of reach when
the chocolate hit the fans and (2)in a nice spot in case of the
highly unlikely event that the Millennium was actually going to
begin that day. It didn't, and the feedback from the experiment
was less than respectful. My former partners disappeared from the
scene to cope with more petty problems and new coincidences
materialized out of nowhere to enable the next stage of my
ongoing quest.
There is an old Negro Spiritual that was in the
1940's made into a "Jazz Soundie", the equivalent of
today's rock video as seen on MTV. I have a wonderful 3-minute
version of "Dem Bones" by the Delta Rhythm Boys, sung
in close four-part harmony; it starts with the refrain,
Ezekiel connected
dem...DRY BONES,
Referring of course to Chapter 37 of the Old
Testament Book of Ezekiel in which the prophet is commanded to
"Prophesy upon these bones: and say unto them, O ye dry
bones, hear the word of the Lord." Whereupon, as in the
refrain of the song,
Oh, de toe bone connected
to de...FOOT BONE,
De foot bone connected to
de...HEEL BONE,
De heel bone connected to
de...ANKLE BONE,
And so on up to "de HEAD BONE". I
hadn't watched my collection of "Soundies" in quite
some time, but humming in the shower late one night, meditating
on my recent neurological studies and lack of satisfaction of
their power to explain processes of mind except in a very
rudimentary manner, the tune suddenly popped into my headbone. It
occurred to me that current neuromechanical models of how the
collection of parts in the brain is supposed to produce mind,
behavior, thinking and perception, was very much a Dry Bones
Model of Neuromechanics. (Substituting brain part names into the
song quite ruins the rhythm however: de caudate nucleus connected
to de...CEREBELLUM, de locus coeruleus connected to de...ANTERIOR
CINGULATE GYRUS, you get the point.)
The textbooks carefully told the student what
was connected to what, and suggested sometimes that a particular
part "was thought to be involved in" some function or
other. And to my further dissatisfaction, slowly compiling again
and again my own map of brain connections, my studies had
revealed that practically every brain part was connected to every
other brain part: each brain map I plotted quite soon became
filled up with arrows, and quite useless. It seemed that
mainstream neuroscience, in spite of its great and rapidly
increasing wealth of assuredly precise data, had little to say
about the functions of all these parts on a systems level;
understanding how to get to psychology from neurology, how to get
mind out of brain, was still at the level of expecting dry bones
to suddenly, as the song's second verse goes, after "dem
bones" have been connected,
Dem bones, dem bones
gonna'...WALK AROUN'...
The neuroscientists, without such divine
intervention as Ezekiel had access to, simply were not able to
show decisively how connections of the nervous system could
produce even simple psychology, much less consciousness itself.
My own efforts to suggest brain systems and connections that
might allow the operation of the habit routine search cognitive
process would therefore be no less tentative and imprecise,
certainly due for major revisions as new evidence was discovered.
In the case of memory, so fundamentally
important to everyday life and to the operation of my proposed
habit routine system, it is therefore still very much a matter of
debate as to how information is stored in or associated with the
properties of the neurons in the central nervous system. The
"data" representing the various types of memory,
including habit routines, must in some sense be "in the
brain" and by extrapolation must somehow be associated with
the properties of neurons and their connections, but the wide
diversity between current theoretical viewpoints illustrates more
our lack of precise knowledge than an emerging paradigm. Perhaps
the most popular model of information storage at present is that
of the adjustment and long-term maintenance of the strengths of
the connections between neurons. This is supposed to occur by the
modification of the neuron's synapses, the junctions by which
neurons communicate using chemical neurotransmitters.
This "neural network" or
"synaptic weight" model lends itself to ready
simulation on a computer and is probably on one end of a scale
ranging from extreme reductionism, to another extreme which
reductionists usually brand as mysticism. An example would be the
ideas about memory advanced by Rupert Sheldrake, that the actual
memory information is resident in some quasi-independent memory
field which may allow such phenomena as telepathy, apparent
reincarnation and so forth, the physical brain being merely the
sender-receiver of memory to the common field by a process of
morphic resonance. (1)
In looking at the broad range of sometimes very enigmatic
properties of memory, and the admitted uncertainty and disparity
of views by the experts, no model should be routinely dismissed
if it has any explanatory power whatsoever.
The synaptic-weight model probably owes its
status to the power and success of computer science, the enormous
investments and hence large number of talented scientists working
therein providing a momentum of opinion which may unduly limit
the credibility of other well-constructed but competing models.
It cannot be denied that very impressive mathematical models and
computer simulations of "intelligence" have been
demonstrated, and shown to have similarities to the ways in which
we believe human intelligence to operate. It has also been well
demonstrated that synapses between neurons (as well as the size
and connectivity of the neurons themselves) can and do change
their characteristics for varying lengths of time under the
influence of learning processes. The power and sophistication of
neural network models (see for example descriptions of the
operation of the Hopfield Network as a mechanism for the
storage/retrieval of information) (2) are certainly impressive. The
fundamental question which remains to be resolved, however, is
whether the brain works anything like a computer. There is
currently raging a most entertaining debate on this subject, some
of the most powerful intellects of our time are joining the
battle, (see, among others, works by Churchland, Claxton, Crick,
Dennett, Edelman, Flanagan, Fodor, Freeman, Gazzaniga,
Hofstadter, Humphrey, McGinn, Penrose, Searle, Tallis, Tulving,
the list is so long there is no recourse but to leave out mention
of many more. Some titles are listed in the Bibliography).
Steven Rose, himself a veteran of many years of
research attempting to identify brain sites involved with storage
of engrams or memory traces, has recently summarized
criticism of the computer-like, information-processing model of
brain operation. (3)
Particularly of interest, as Rose points out, is a critique by
the neurophysiologist Walter Freeman, for it is solidly based on
research findings: Freeman insists that, although changes to
various individual neurons can be observed to happen as a result
of learning, the "information" that is learned does not
subsequently exist as "bits of data" recorded in these
neurons (the computer paradigm). Rather, the memories of the
learning exist as fluctuating dynamic patterns of electrical
activity generated by the entire brain. As Rose puts it,
[The] experiments say that it, the engram, is not confined
to a single brain region. But I want to go further than this,
and to argue that in an important sense the memory is not
confined to a small set of neurons at all, but has to be
understood as a property of the entire brain, even the entire
organism. (4)
An intriguing suggestion has been that the
storage of information in the brain is analogous to the storage
of information in a hologram, a model which was first developed
by the neurosurgeon Karl Pribram in the 1960's. (5) The idea that brain activity might be
non-local, a process of the generation of distributed waves of
activity which interact to form interference patterns, had been
suggested in 1942 by Karl Lashley, whose pioneering research on
the brain had inspired Pribram during their collaboration at
Yerkes Laboratories. Freeman's experimental findings, as well as
the observations of Steven Rose above, are exactly what one would
expect from a brain operating on holographic principles. The view
of memories existing as "fluctuating dynamic patterns of
electrical activity generated by the entire brain", could
not embody holographic principles more strongly.
Although criticism of the so-called holographic
paradigm has come from many directions, the parallels between the
mathematical and physical facts of optical holography and many
known properties of memory and the brain suggest that further
research will tend to support rather than discredit the model. In
a recent paper Pribram elaborates on some of these parallels:
The following properties of holograms are important for
brain function: (1) the distribution and parallel
content-addressable processing of information a
characteristic that can account for the failure of brain
lesions to eradicate any specific memory trace (or engram);
(2) the tremendous storage capacity of the holographic domain
and the ease with which information can be retrieved (the
entire contents of the Library of Congress can currently be
stored on holofische, or microfilm recorded in holographic
form, taking up no more space than is contained in an attache
case); (3) the capacity for associative recall that is
inherent in the parallel distributed processing of holograms
because of the coupling of separate inputs; and (4) the
provision by this coupling of a powerful technique for
correlating (cross-correlations and autocorrelations are
accomplished almost instantaneously). (6)
It is a curious fact of the history of
neuroscience that Pribram's work during the 1960's and 1970's was
almost unanimously rejected by the mainstream: he was for two
decades practically the only proponent of the theory of
distributed representation of memory (distributed coding) in the
brain. At the time, nearly all theoretical work leaned strongly
toward the assumption of detector-cell coding, (7) a model strictly analogous to computer,
bit-storage processes, with a precise location in the machine
being responsible for the storage of a uniquely defined unit of
information. Today the mainstream neuroscientists have taken the
opposite tack: distributed processing and storage is their
byword, yet Pribram's holonomic theory is still widely rejected,
even though in an important sense it is part of the foundation of
recent theory. Francis Crick's assessment is typical:
This analogy between the brain and a hologram has often
been enthusiastically embraced by those who know rather
little about either subject. It is almost certainly
unrewarding, for two reasons. A detailed mathematical
analysis has shown that neural networks and holograms are
mathematically distinct. More to the point, although
[artificial] neural networks are built from units that have
some resemblance to real neurons, there is no trace in the
brain of the apparatus or processes required for holograms. (8)
To state that neurosurgeon Pribram and his
recent mathematician colleagues "know rather little about
either subject" is a bit stiff, and the observation that
there don't seem to be any lasers or such holographic equipment
in the brain itself demonstrates ignorance of the two subjects.
Pribram counters such criticism with the warning, "It is
important to realize that holography is a mathematical invention
and that its realization in optical systems...is only one product
of this branch of mathematics." In other words, optical
holography is merely a special case of a wider and more
fundamental process for the encoding and reconstitution of
information. For this reason it was suggested that the term holonomic
(9) be used in
reference to brain/mind properties, a term I shall adopt here.
The term holonomic as used in physics, also indicates that the
process is not a static, frozen-in-time representation as is a
hologram, but a dynamic, continuous one.
Further rebuttal, including a short history of
the criticism of the holonomic theory can be found in a recent
paper by Pribram and his colleagues. (10) The most recent and complete
exposition of holonomic theory is presented in a book covering
the 1986 John M. MacEachran Memorial Lecture, (11) delivered by Pribram. The book
demonstrates that the holonomic theory has progressed both
conceptually and mathematically far beyond its introductory
position of the 1960's; it is the original and necessarily
simplistic exposition of the theory which is still attacked by
the critics of today who remark (along with other trivial
complaints) that "there don't seem to be any lasers in the
brain".
Other criticism of the holonomic model of memory
storage and retrieval has been derived from the perceived
contradiction with the accepted dogma that regulation of synaptic
weight must certainly be the only possible storage mechanism in
the brain. Synaptic weight distributions are quite amenable to
neural network, viz. computer-like models of brain/mind
function, but it was very difficult to see how synapses could
function as a storage medium for the interference patterns
implied by holonomic models. Yet the idea of learning and memory
storage by neural networks is itself by no means universally
accepted. Concerning the much-touted ability of computer
analogues of neural networks to learn, Jerry Fodor remarked:
"Much has been made of this, but, in fact, it's a tautology,
not a breakthrough." (12)
A very promising idea which would obviate some
of these objections to the holonomic model has been the recent
suggestion that the site for storage of information is not the
synapse per se, but associated with the microtubules
making up the cytoskeletal structure of the neuron itself. (13) (The synapse is
known to be in indirect yet intimate contact with the microtubule
structure of the neuron.) This model has the immediate advantage,
as Hameroff points out, of increasing the potential effective
complexity and storage capacity of the brain by about seven
orders of magnitude, (14)
but there are many other attractive aspects to the model as well.
It would seem that the synapses are concerned
primarily with the large-scale systems of the brain, they are the
functional units enabling coordination and signal transfer
between distinctly separate, sometimes distant locations. For
example, they enable the experimentally-demonstrated phenomena of
the sequential processing of sensory information from primary
sensory cortex through several levels of associational cortex.
Another example would be a neuron in a brain-stem nucleus such as
the locus coeruleus: it may project the entire distance to an
area of the cortex before synapsing on another neuron. As a first
consideration, the synapses thus seem involved with the switching
and transfer of information (analogous perhaps to the transistors
or switches in the central processor of a computer). To assign
them the double duty of also being the storage site for
the information which they manipulate seems merely a default
position (the synaptic-weight model). There is more logic to the
idea that the information that is manipulated via the synaptic
connections has been accessed in structures or locations
independent from the synapses, otherwise the duty of the synapse
in one function would seem to necessarily limit its capacity for
the second function.
Having looked into the neural network models of
brain function, I realize how easy it would be to reject the
foregoing argument if one is convinced of the validity of such a
model. But it is my own view that, although neural networks seem
to simulate brain/mind operation in some trivial respects, the
"connectionist" paradigm as it is called is as
primitive and misleading a model of the human brain/mind as is
the planetary model of the atom (discussed in chapter 2). From
this viewpoint, neural networks may be useful for modeling
"intelligent" processes up to the level, say, of
creating robots for assembly-lines or for playing chess, but to
extrapolate from there to say that by adding a few more bells and
whistles, or even many additional layers of mechanical or
electronic complexity to these beasts, we will then have
duplicated the human mind in a machine... Well, to me and many
others that is sheer folly. I am all for letting the
connectionists connect, and the AI (Artificial Intelligence)
crowd continue their quest to reproduce themselves asexually, but
they do tend to pummel the less-well financed competition with
epithets worthy of the flat-earth advocates of a bygone age.
Hence the present riposte.
The combination of the holonomic
storage/retrieval model with the hypothesis of micro-tubule based
storage sites thus seems even more promising: Hameroff's paper
even suggests that the microtubules of neurons might provide a
location where coherent photons would operate (viz., the
kind of light necessary for optical holography). In constructing
my own model of brain operation, I have tried not to depend
irrevocably on any particular view now contending, including the
more conservative ones. Yet due to the wide disagreement between
the positions of the several groups of theorists, I have felt
justified to freely use some of the more speculative suggestions
such as holonomic operation and storage, if only as temporary
visual, heuristic devices. Since my intention is merely to
suggest a possible mechanism for the operation of the
habit routine system, (and at the present stage of neuroscience,
it would be unrealistic to hope for more), my overall theory of
psychedelic experience would not be damaged by further research
indicating the brain had many further tricks up its sleeve. The
holonomic, microtubule hypothesis, although it may well be found
to describe the actual operation of the nervous system, will for
my purposes merely provide a convenient conceptual model
facilitating the understanding of the operation of the brain
systems responsible for habit routine search and suspension and
other proposed operations involved with psychedelic experience. I
thought it valuable, however, to introduce the holonomic model on
a level which would show that it was far more than "New Age
Techno-Babble", an implied if not explicit critical view now
prevalent.
Figure 2 illustrates the location of just a few
of the major brain-parts for the benefit of the general reader.
But in the interest of brevity and concision, I will not attempt
to diagram or explain entry-level details of the model I shall
now present, either in the case of the properties of neurons, or
the general views concerning the functions of the various brain
components taking part in my own theoretical view. For the
layman, the Glossary will be of some help, but a survey of a
textbook such as Principles of Neural Science (Kandel,
Schwartz & Jessell), would be indispensable for evaluating
the proposed model in detail, and comparing it to standard
textbook views representing current paradigms.
FIGURE 2. The Right Half of the Human Brain.
Viewed from a vertical plane bisecting the brain into its
left and right hemispheres. A through F: Areas
of the cortex. A: Prefrontal area. B: Anterior
Cingulate Gyrus. C: Frontal Lobe. D: Parietal
Lobe. E: Occipital Lobe (primary visual cortex). F:
Temporal Lobe: most of this area of the cortex is on the
outside of the far side of the brain, hidden in this view. G:
Cerebellum. H: Thalamus. Encircling the Thalamus are
the Hippocampus, the Amygdala, the Basal Ganglia and other
parts of the limbic system. I: Pons. J:
Midbrain, area in which are found the various brain stem
nuclei including the Raphe Nuclei, the Locus Coeruleus, the
Substantia Nigra, etc. K: Medulla. L: Spinal
Cord.
(Modified from Nieuwenhuys, et. al., The Human Central
Nervous System).
I have mentioned that most brain areas are
connected to most other brain areas, the multiplicity of
connections between parts becoming obvious and soon quite
bewildering when one starts examining the various brain
"maps" in Nieuwenhuys' book, for example (the source of
the diagram in figure 2). In addition, it is found that nearly
all of the connections are two-way, the connections between the
thalamus and the primary sensory areas of the cortex, for
example, being reciprocated by nerve pathways (backprojections)
in the opposite direction. It is problematic therefore to
construct a diagram for the supposed "flow of
information" in the brain: if the retina of the eye, for
example, sends its "visual data" to the thalamus (which
has been likened to a relay-station for sensory data), and then
the thalamus sends this signal to the primary visual cortex for
the first stages in the processing of visual information, why
should the primary visual cortex send a nerve pathway directly
back to the same area of the thalamus from which it has just
received the data? The backprojection is not insignificant:
recent findings indicate in the case of vision that there are ten
times as many nerve fibers in the "backwards"
direction as in the direction in which "information" is
supposed to flow! The size and importance of the various
interconnections (15)
seems to indicate that the actual sensory
"information", the environmental data ENV in figure 1,
constitutes only a minor part of what is being
"processed" in the brain! Current computer
"data-flow" models of brain operation cannot explain
the facts of the existence and relative importance of
backprojections, as even the best workers in the field will
admit.
But this is exactly what one would expect for a
brain architecture that operated according to the habit routine
model of cognitive function. The environmental data merely
provides cues for the elaboration of the far more complex
informational entity of which we become aware, the habit routine
complex. It is far more complex, because it is generated from the
entirety of previous experience stored in memory, whereas the
actual environmental data is quite limited in scope not least by
the limits of the sensory organs themselves. In size and
complexity, the nerve pathways carrying the primary sensory
information to the cortex are among the less important
connections of the brain. To be sure, the environmental input is
necessary: when you shut your eyes, vision promptly ceases. But
this effect itself may be heavily dependent upon the operation of
habit routines. We are all absolutely and automatically certain
that vision must cease when we close our eyes, and would
be profoundly confused, (if not shocked into psychosis!), were it
to be otherwise, even for a few seconds.
There is a computer analogy that could be made
in the attempt to account for the curious facts of neural
reciprocating connectivity, that the signaled area must send back
a return signal indicating that it has received information, like
two modems do as they talk to each other. But this would not
explain why return pathways are so much larger. I would propose
that something much more interesting is taking place. In the case
of the nerve pathways from the thalamus to the primary sensory
cortex areas (and back again) for the various sensory modalities,
I believe it is useful to hypothesize that a reverberation is
being established with the two-way signaling, and that this
reverberation is a dynamic informational entity having
holonomic properties.
The thalamo-cortical reciprocating nerve
connections set up for each sensory domain a dynamic
reverberating holoprojection of information, which is
constantly updated and modified with the newly arriving signals
from the sensory organs. It would require a much higher density
of nerve pathways to set up and maintain such reverberation than
to feed in the flux of newly arriving ENV data, thus explaining
the relative importance of the brain connections between the
sensory receptors, the thalamus, and the areas of the sensory
cortex. The suggestion of similarity to the projection of a
holographic image is intentional, for I believe that, not only
are the mathematical principles which predict and describe
optical holography applicable to memory storage, but also to the
ongoing operation of many of the systems of the brain. In
comparison to optical holography, it can also be maintained that
the relation between a given unitary nerve signal (the electrical
action potential of a neuron) and the overall holoprojection to
which it contributes, is analogous to the relation between the
unitary nature of one grain of photoemulsion making up a hologram
(the "photograph" of the interference patterns produced
in optical holography), and the resulting projected holographic
image. The single grain of emulsion on the photographic plate may
only be either "on or off" like the neuron, yet it
theoretically represents the entire holographic projection, (16) albeit with a
resolution of zero. It is the same for a single action potential:
it represents the entire holoprojection, but with zero
resolution.
Someone familiar with holography would certainly
ask, but how and where are interference patterns produced,
certainly any holonomic process implies their existence, for it
implies the interference of two or more signals? Dropping one
pebble into a still pond produces concentric waves, but dropping
two pebbles produces an interference pattern between the two sets
of waves. So it may be with the nerve signals of the brain. It is
well known that neurons in their various nerve pathways have a background
rate of firing which, for all intents and purposes, seems to be
merely random noise. Here is pebble number one. Pebble number two
(in the case of the primary sensory holoprojections), is the
impinging signal from ENV (of figure 1), the signal coming from
the sensory receptors.
Thus the resulting holoprojection is the product
of a dynamic interference pattern resulting from at least two
distinct signals, and is amenable to expression as mathematical
transform coefficients analogous to the mathematical operations
which describe optical holography. In the nerve pathways
maintaining a primary sensory holoprojection, the microtubules of
these neurons record and dynamically maintain the transform
coefficients which represent the information necessary for the
neuron firings to maintain the reverberation. The coefficients
are constantly updated with the sensory signal from the
environment, which also exists as a transform of the interference
patterns actually received by the sensory receptors. Thus there
are two sets of coefficients representing the two signals,
together they contain the information necessary to maintain the
dynamic holoprojection in time. It will be seen that even the
background firing of the neurons, the resident signal, is not
merely random noise, for it is generated from the coefficients
resident in the microtubules and represents the holoprojection in
temporal cross-section. The constant arrival of the ENV signal
produces the dynamic aspect of the primary holoprojection.(note)
But the combination of signals to produce
interference patterns does not end with the primary sensory
holoprojections, for as I shall explain below, holoprojections themselves
combine and overlap, they become superimposed under the guidance
of certain brain components so as to produce further interference
patterns and thus further composite holoprojections. It
can be seen that the "processing of information" in the
brain is therefore accomplished using entire simultaneous fields
of bound "data" from several, or even the entirety of
all ongoing processes. The hypothesis of such a process conflicts
radically with the computer, neural network model of the brain in
which the serial processing (in parallel pathways) of discrete
bits of information is the proposed mechanism. If experimental
results begin to confirm the holoprojection model of brain
operation, they will be a significant argument against the
pursuit of strong Artificial Intelligence as it is presently
conceived. Let us see how the fields of information I have called
holoprojections might function in stages of brain operation
beyond the primary sensory realm. First let us take a closer look
at the thalamus, which plays so central a role in generating the
primary sensory holoprojections which are the data fields upon
which all further brain activity is based.
The thalamus itself is composed of many
different nuclei, widely connected to other brain areas and
interconnected as well. Thus in discussing the various functions
of the thalamus, it must be kept in mind the great diversity of
independent yet interrelated parts and functions comprising this
centrally-important component of the brain. In the case of
vision, after the signals have passed from the retinae through
the optic chiasm which combines and distributes the visual
signals from both eyes to the left and right hemispheres of the
brain (the thalamus also is divided bilaterally), the visual
signal that is to be used for updating the primary visual
holoprojection enters a thalamic nucleus called the lateral
geniculate nucleus, or LGN. The LGN then signals the first stage
of the part of the cortex involved with vision, the primary
visual cortex, and it is from this area that we note the very
important nerve pathways which return directly to the LGN. It is
merely a convenience to say, for example, the signal is
"passed" from here to there, and "then"
passed...etc., for we must remember that all these processes are
dynamic, continuous, and as I have proposed, reverberating and
holonomic.
The function of the LGN of the thalamus thus
appears to be as a "driver" for the reverberation
between the LGN and the first stage of the visual cortex. As I
have suggested, this reverberation may be thought of as a
holoprojection which has at least two functions. Firstly, this
informational entity is the first stage in the generation of (the
visual aspect of) the habit routine complex, it contains the
information which will activate from the frames of memory (stored
in distributed manner in the same visual areas of cortex), the
actual information which makes up the habit routine presented to
thinking2 processes. Secondly, since this holoprojection carries,
at least potentially, the original or "genuine" visual
information, it will be used under certain circumstances to
generate aspects of the visual scene that are detected as
significant and to which the attention is directed. This will
occur by a comparison or superimposition of the primary visual
holoprojection with another holoprojection set up by the habit
routine search system. (As explained below, significance
detection may use the primary sensory holoprojections, or
the memory data activated by these holoprojections instead).
An additional function of the primary visual
holoprojection results in the phenomenon of iconic memory,
the very short term visual memory trace that has been
experimentally demonstrated. (17) An informational fragment of the
primary visual holoprojection, since the entire holoprojection is
being constantly updated with new visual data, would be expected
to have a very short "half-life" comparable to the 200
to 500 millisecond iconic memory (up to three or four seconds
under certain experimental conditions). Experiments with iconic
memory have shown that it persists for greater periods when
preceded and/or followed by a simple dark field containing little
or no new visual information. Likewise, it may be interfered with
by the process of masking in which a bright field of view,
or interfering patterns are shown. This is exactly what would be
expected for the visual holoprojection model. A paucity of new
visual data arriving to update the holoprojection would allow the
reverberation to persist "as is" for a greater length
of time. Data intentionally designed to confuse or interfere with
the iconic memory would have the effect of overwriting the
relevant aspects of the holoprojection (the transform
coefficients stored in the microtubules of these neurons).
The extraction of the iconic memory must occur
by other systems involved with thinking2 processes, again
probably by the comparison or superimposition of holoprojections.
There is more than speculation in the idea that such projections
might be superimposed and compared to show similarities and
differences, for the same kind of process can be carried out with
optical holograms (in practice, I am informed, there are
technical difficulties to overcome, but no theoretical
restrictions). Two slightly different optical holograms, for
example, could at least theoretically be projected so that they
cancel each other except for the aspects in which they differ:
only the differences would appear in the projected image.
Likewise, two radically differing holograms having just a few
identical features could be projected to emphasize their common
features. In the brain, the process might be as simple as the
addition and subtraction of the transform coefficients stored in
the microtubules of the contributing neural systems. This would
produce another set of coefficients representing the
superimposition.
At the same time that the primary visual
holoprojection is being generated, of course, all the other
sensory systems are generating their own holoprojections, by
similar mechanisms involving sensory receptors, the thalamic
relay nuclei concerned with those senses, and areas of the
cortex. Thus for hearing we get an audio holoprojection from
which can be extracted echoic memory (analogous to iconic
memory). The audio holoprojection is used to activate the audio
domain of the frames of memory going into the generation of the
habit routine complex. Tactile sensations and proprioception
likewise produce their reverberations, and so forth.
The binding and superimposition of all the
primary sensory holoprojections is accomplished by a scanning
mechanism only recently detected by neurological experiments. (18) This scanning
operation is also carried out by a nucleus of the thalamus, the
intralaminar nucleus. Now what is scanned is not the actual
primary holoprojections themselves, but the memory information
which they activate in the various regions of the cortex. This
activation occurs as the holoprojection signal transits through
the pyramidal cells of the several layers of the cortex
taking part in the reverberation. The sum total of all ongoing
sensory holoprojections, impinging on the memory data distributed
in the same areas of the cortex that take part in the set up of
the various holoprojections, activates this memory data such that
the intralaminar nucleus, acting again as a driver for the
generation of a holoprojection, creates the habit routine complex
holoprojection. The memory data in this process is thus analogous
to the role of primary sensory data in the generation of the
primary sensory holoprojection. Remember that we are
hypothesizing that this memory data is associated with the
microtubules of the neurons in the cortex and not their synapses,
so while the neurons and their synapses in the circuit between
the thalamic relay nuclei and the cortex are maintaining the
primary holoprojection using the signals from the sensory
receptors, the holoprojection itself, as an interference pattern,
is resonating with the stored interference patterns in memory
resident in the microtubules.
The habit routine complex holoprojection is the
bound informational entity presented to thinking2 processes,
having the various properties already described in chapter 3. The
memory information used to generate the habit routine is, as just
proposed above, analogous to the original sensory information:
the sensory signals are used to set up the primary sensory
holoprojections, and the activated signals from memory are used
to set up the habit routine holoprojection. In each case we have
a thalamic nucleus acting as the driver for the process, using an
input of transform coefficients to produce the holoprojection.
But the intralaminar nucleus scan which sets up the habit routine
is deriving its input from the entire cortex, not just the
primary sensory areas. The habit routine complex is much more
than just primary sensory information taken from memory, for
remember that a habit routine contains pre-programmed
associations with ideas, with habits of thinking, and it also
contains recommended actions (including not only physical
responses but thoughts, opinions, implied value judgments, etc.),
that represent the sum total of ways in which similar situations
were dealt with or reacted to in the past.
The higher domains of the cortex itself are
using the primary sensory holoprojections to derive associational
information such as that concerning depth perception, for example
(from both audio and visual sources in combination), as well as
perception of motion, types and categories of perceptions, as
well as cross-modal associations. Thus the primary
holoprojections generate far more from the memory data than just
elementary sensory information. This is why the ILN scan cannot
be simply of the primary holoprojections themselves, but of the
result of the entire sequential associative process they generate
in the cortex. The process extends over the entire cortex. For
instance, at the most advanced level of associational processes
in the frontal cortex regions, you have a bound, unitary, and
multi-sensory short-term-memory of events (and your reaction to
these events) that just happened a moment ago, produced by
successive stages of associational cortex operation. This memory
information is also scanned and becomes part of the habit routine
complex. In this sense even current experience is very much like
a reverberation, for current evaluation of reality is based upon
the interpretation of reality just experienced which has been
re-injected into the ongoing habit routine complex. Thus the
significances that thinking2 decides to examine more closely by
extracting information from the primary holoprojections are
actively perpetuated. Using this mechanism we can increase the
proportion of "raw reality" in the current habit
routine to override the "interpretation" of reality
that would be supplied by the unmolested habit routine alone. And
here is where the psychedelic experience comes in. The process
which is so startlingly activated by psychedelic drugs, is the
very same process that we can accomplish, if on a more limited
level, as just described. Let us look closer at this overall
process, for it involves the generation of additional composite
holoprojections which have more to do with conscious thinking2
operations, including free will, than with automatic sub- or
pre-conscious thinking1 processes and their holoprojections.
The nuclei of the thalamus are also important
for the generation of these composite holoprojections, but at
this stage, other brain nuclei become partners with the thalamus
and cortex. Again, these older, more "primitive" parts
of the brain act as drivers in dialog with the cortex to produce
the composite informational fields. (19) Among the brain components taking
part are the locus coeruleus and raphe nuclei of the brain stem,
the amygdala, hippocampus, the basal ganglia and cerebellum,
among others. It is certainly an ambitious statement to say that
I will attempt to explain the role of some these brain areas, but
here goes:
First let us consider the role of the locus
coeruleus and the raphe nuclei, for it is the nerve pathways
connecting these two brain areas with the cortex and with each
other that are the primary site of biochemical action of the
psychedelic drugs. It is with these nuclei that I must show how
significance detection and the suspension of habit routine is
accomplished. I would propose that the locus coeruleus is the
master functioning body, the driver which through dialog with
essentially all brain areas but particularly the thalamus, the
raphe nuclei and the cortex, produces the composite
holoprojection containing information about significance or salience
not only in the environment, but also even in the ongoing
processes of thought leading to ideas, opinions, etc. I will
refrain from presenting a diagram of the connecting nervous
pathways between the various brain areas cited as it is extremely
difficult to do so meaningfully at this stage. Certainly, as I
have already said, there are plenty of connecting pathways
between all of these brain parts, there are rather too many, it
would seem.
Now the statement that the connections between
the raphe nuclei, the locus coeruleus, and their connections to
the thalamus and cortex are the primary site of biochemical
action of the psychedelic drugs is based quite solidly on recent
brain research. (20)
We know that LSD and other psychedelics, for example, exert
powerful influence on the operation of neurons emitting and
receiving at their synapses the neurotransmitter, serotonin.
There remains considerable mystery as to how the drugs
react with these neurons, whether they activate or inhibit
serotonin receptors, which types of serotonin receptors are
affected, and so forth. There is also considerable mystery as to how
these affected neurons might bring about the overall
psychological result. The first question remains, at the present
state of research, very difficult to answer. But it is with the
second question that I believe we should start, for there seems
to be enough information now available to formulate a model.
It is generally agreed by neuroscientists today
that the locus coeruleus acts as a kind of novelty or
significance detector, its activation (in animals) has been shown
to increase in response to stressful or noxious stimuli,
preferred food and other complex arousing events, and even to
changes in body systems such as the level of oxygen or carbon
dioxide in the blood. The psychedelic drugs have been repeatedly
shown to greatly increase the activity of the locus coeruleus,
but not when applied directly to the cells which make up the
nucleus. Thus it has been hypothesized that the state of the
locus coeruleus must be influenced by another nucleus or system
which itself is directly affected by psychedelics. Some relevant
facts concerning the locus coeruleus:
The locus coeruleus (LC) consists of two dense clusters of
noradrenergic neurons located bilaterally in the upper pons
at the lateral border of the 4th ventricle. The LC, which
projects diffusely to virtually all regions of the neuraxis,
receives an extraordinary convergence of somatic, visceral
and other sensory inputs from all regions of the body and has
been likened to a novelty detector. Thus, the LC represents a
unique nodal point both for the detection of significant
changes in the internal and external environment and for
relaying this information to the remainder of the central
nervous system. It is not surprising that hallucinogenic
drugs, which produce such dramatic changes in perception,
would alter either directly or indirectly the function of LC
neurons. (21)
In keeping with the holonomic model, I would
propose that the locus coeruleus is the driver which produces a
composite holoprojection consisting of the superimposition and
canceling of primary holoprojections including the habit routine
holoprojection to yield a field of information concerning significances
in the ongoing experience of the organism. The detection of
significance, or salience, normally is derived from the same
memory data from which the habit routine complex is generated,
and is merely a repeat detection of salience that has occurred in
the past. When the test animal mentioned above is shown a
preferred food, for instance, and its locus coeruleus is shown to
increase in activity, the salience detected is obviously relative
to memory data of the preferred food. But when I am the test
animal in a French restaurant, when some unknown yet succulent
dish is placed before me, I begin to extract information directly
from the primary sensory holoprojections to try to deduce the
composition and possible methods of preparation of the mysterious
delicacy. Memory information in the habit routine will still be
the primary source of information in these deliberations, but my
Attention will guide the process to actual examination of the
"genuine" sensory data contained in the primary
holoprojections. As I mentioned above in introducing the
functions of the primary holoprojections, we see that salience
detection may use the primary data, but normally, and
routinely, salience is merely a repeat performance of previous
detection, based on the habit routine complex itself.
The connections of the locus coeruleus which
accomplish the detection of normal salience from the habit
routine data may be simply the interconnections with the cortex.
The locus coeruleus receives a modest input from only one area of
the cortex, the prefrontal cortex, but it sends its output to the
entire cortex. We see again (as in the case of the pathways
between the thalamus and the primary sensory cortex) the
situation where the "return" signal is far more
important than the "input" signal, and this suggests,
as in the nervous pathways taking part in the generation of the
primary sensory holoprojections, a reverberation, in this case
the salience detection holoprojection. (22) The signal from the prefrontal cortex
is the final stage of the entire process of association, so it
will obviously represent the complex associational memory data of
past salience detection that was experienced. The return pathways
to all cortex areas might also be thought of as facilitating the
cancellation or ignoring of all features of the habit routine
except for the salient entities, so that the resulting
holoprojection contains only information about these entities.
Thus the Attention is directed to the salience which practically
jumps out of its surroundings. The locus coeruleus has several
inputs besides that from the prefrontal cortex, but these inputs
function to modulate the holoprojection generation in various
ways. A particularly important control of the process is
accomplished by the raphe nuclei.
The raphe nuclei of the brain stem are
particularly important to salience detection and to the
psychedelic experience because they contain the great majority of
neurons of the brain which use serotonin as a neurotransmitter.
Some of the earliest work on the effect of LSD in the brain found
that "LSD and other indoleamine hallucinogens...have potent,
direct inhibitory effects upon serotonergic neurons located in
the raphe nuclei of the brainstem." (23) Now it has been well established that
the serotonergic neurons of the raphe nuclei project heavily to
the locus coeruleus, and likewise that serotonin inhibits the
firing of the type of neuron found in the locus coeruleus. (24) As mentioned
above, studies have also confirmed the psychedelic agents have as
their target at least some of the many types of serotonin
receptors on neurons both of the areas signaled by the raphe
nuclei, and on the raphe serotonin neurons themselves
(autoreceptors). The raphe neurons also project widely throughout
the brain, to all areas of the cortex, (strongly to the
prefrontal cortex from which the locus coeruleus derives its
input), the thalamus, the amygdala, virtually the entire nervous
system. Thus I would propose that the raphe nuclei are the
principle mechanism of control, the driver which guides the mode
of function of salience detection, as well as the manner in which
the detection is used and subsequently stored in memory. It
appears that Attention and other thinking2 process use the
serotonergic system of the brain, based in the raphe nuclei, to
direct the detection and use of salience, but not simply by
"inhibition" as would be implied by the observed
"inhibitory" action of serotonin on the neurons of the
locus coeruleus, or the observed "inhibition" of
serotonergic neurons by LSD.
It is a curious fact of the human brain, that
fully 75% of the neurons therein are supposedly "inhibitory
neurons", whereas in the monkey the figure is 45%, and in
the cat a mere 35%. (25)
Clearly these facts must have some tremendously important
significance, not only for the type of functioning they imply of
the brain, but in some sense they must tell us something very
important about the psychological differences between man and
animals, particularly the great disparity of intellectual
capacity. A not very convincing speculation has been that the
large proportion of inhibitory neurons allows a
"streamlining of thinking" in which groups of brain
cells are more quickly returned to a state of readiness after
some operation. (26)
I would propose that the inhibitory neurons do not
"inhibit" in such a literal manner, but rather are
concerned with the superimposition of holoprojections in which a cancellation
or subtraction of information results, such as the
manner in which all peripheral information from memory going into
the generation of the salience holoprojection is removed so as to
yield a composite holoprojection consisting of only the
detected entities. It might be said that human mental powers, as
opposed to that of lower animals, reside primarily in the ability
to discriminate between and detect widely differing types of
significance not only in the environment but within thought
patterns of abstractions and concerning ideas and
constructs of the intellect. These human feats, I would propose,
are accomplished using the wide network of inhibitory neurons
functioning to produce composite holoprojections derived through
the comparison and subtraction of informational fields one
from another, to reveal patterns the complexity of which far
outstrips the power of lower animals to detect.
There are probably several brain operations,
brought about by combinations of brain parts including a nucleus
of the midbrain or brainstem as a driver, which generate such
composite holoprojections. The detection of emotional content, or
valence, is probably accomplished using the amygdala as a
driver in dialog with the cortex and other nuclei, superimposing
the same primary holoprojections as are used for salience
detection. But the salience detection of the locus coeruleus,
controlled and modulated by the raphe nuclei connections
throughout the brain, generates what is probably the most
important holoprojection of the brain/mind, (or in any case,
second only in importance to the habit routine holoprojection).
And it is upon the generation of this salience detection
holoprojection that the psychedelic drugs exert their effects.
Now it was soon noticed, after the inhibitory
effect of LSD and similar psychedelic drugs on the raphe nuclei
was discovered, that other psychedelic agents such as mescaline
and the phenethylamine family did not produce the inhibition. The
indirect effect on the locus coeruleus was, however, as
important as with LSD. The effect is indirect, for as
mentioned, the application of psychedelic agents to locus
coeruleus neurons themselves fails to alter their activity. But
since the locus coeruleus salience detection system involves the
entire cortex, and the serotonergic neurons of the raphe nuclei
project to the entire nervous system, it is evident that the
control of salience detection would be alterable at many
different sites of potential psychedelic drug action. A direct
change in the raphe nuclei is the possible primary action in the
case of LSD, whereas a change in the effect of the
signaling by the raphe neurons, either in the locus coeruleus or
possibly the cortex itself, might be the mechanism for mescaline.
The overall effect is in both cases a change, which appears to be
an increase, in the rate and type of salience detected by the
locus coeruleus system. I am tempted to repeat some of Huxley's
observations about significance quoted at the end of chapter 3,
but instead will quote Alan Watts, here writing about his first
experiment with psychedelic drugs:
"I have said that my general impression of the first
experiment was that the "mechanism" by which we
screen our sense-data and select only some of them as
significant had been partially suspended. Consequently, I
felt that the particular feeling which we associate with
"the meaningful" was projected indiscriminately
upon everything, and then rationalized in ways that might
strike an independent observer as ridiculousunless,
perhaps, the subject were unusually clever at rationalizing.
However, the philosopher cannot pass up the point that our
selection of some sense-data as significant and others as
insignificant is always with relation to particular
purposessurvival, the quest for certain pleasures,
finding one's way to some destination, or whatever it may
be." (27)
I have suggested above that there are two modes
of salience detection, the first merely automatic and based upon
previously experienced situations, and a second which is based on
the genuine data of the primary holoprojections. Remember my
little story of noticing the grey rock in the middle of the
pathway. Automatic salience detection brought it to my awareness,
and interpreted it relative to previous experience. Yet some
unconsciously perceived anomalous data, a slight movement, a
color not quite in keeping with experience, caused me to suspect
an error, and choose to examine the raw sensory data
itself and Decide that something was amiss. At this point the
original habit routine was overruled, and a new interpretation
actively demanded by the Attention. This was accomplished by use
of the working memory, thought to be a function of and resident
in the prefrontal cortex, the same cortical area from which
the locus coeruleus receives its sole input. Remember also my
stated feeling that under the influence of psychedelics, it seems
that the habit routines of interpretation in this case would be
at least momentarily suspended, and after a moment multiple habit
routines might arrive at thinking2 processes. All these
observations seem to indicate that psychedelics would be
interfering with the habit routine holoprojection, rather than
the salience holoprojection. But according to my neurological
model so far, it would appear that psychedelic agents interfere
with the control exerted on the salience holoprojection by the
raphe nuclei and the serotonergic neurons extending widely to all
areas of the brain.
I would now propose that the profound
alteration of the salience holoprojection by psychedelics,
illustrated both by neurological data and by the practical
observations of Huxley, Watts, and many others, causes the
individual, using the conscious mechanisms of thinking2, to
himself suspend the dependence on the habit routine
holoprojection. It is the cumulative effect of not only added
salience detected in the ENV both external and internal, but of
the interpretation of this increased salience as itself extremely
significant, that leads to a veritable avalanche of salience
detection which simply overwhelms normal acceptance of and
dependence on the habit routine system.
The habit routines are still assembled and are
there in the background, but they are almost completely ignored
by Attention, Decision, and other thinking2 processes amidst the
flood of salience perceived. Thus, the psychedelic experience is,
in an important sense, voluntary, and this would explain
the ability to achieve such states through meditation and other
voluntary mechanisms. That the habit routines are still assembled
and available to some extent is illustrated by the common ability
during the lucid end-stages of psychedelic experience to
recognize a duality in experience: a perception of the way things
appear with "the doors of perception" cleansed, and a
simultaneous recognition of how the same scene would appear in a
normal state of mind governed by habit routine. Such realization
extends to the perception one's personality traits, one's
prejudices and automatisms of behavior, from a viewpoint that is
essentially outside of the self and beyond the ego. In
this state I believe, the habit routines have been completely
suspended in function, and salience detection is using the
information of the primary holoprojections.
At the request of thinking2, the primary sensory
holoprojections become the subject of meticulous examination,
genuine reality floods through, the habit routines ignored. The
raphe nuclei must in some sense be acting as a control mechanism
for this switch-over, allowing the locus coeruleus system to
create superimpositions of the genuine data rather than the
memory data. This switch-over probably occurs in the cortex
itself, by the control exerted by the serotonergic neurons from
the raphe nuclei which contact both inhibitory interneurons and
the pyramidal neurons of the cortex. (28)
Experimental evidence supporting the above model
relating the neurological operations of brain systems and the
habit routine search and suspension hypothesis of normal and
psychedelic functioning has been easy to find in the literature.
Of course, due to the current state of neuroscience, it is often
found that alternative interpretations of experimental results,
leading to radically different models, is possible. Such is the
case here, and for any specific experiment which I might use as
evidence for my model, others would find it just as easy to use
the same data for another view. For this reason, as well as in
the interest of brevity, I shall mention only a few examples. A
thorough survey would require at least another volume, and the
more important chapters of the present volume still await
exposition.
A vast body of literature concerning brain
function and its perturbation by brain lesions goes back more
than a century. A great many studies have been done concerning
patients whose brains have sustained damage through accidents or
necessary brain surgery, and experimentally, countless numbers of
animals of every description have undergone destruction,
disconnection or removal of various brain areas in the attempt to
localize various sensory, motor, and cognitive functions of the
brain. With such a wealth of evidence, it is not hard to find
studies that might support almost any model one would care to
dream up.
I will mention just a few cases which have been
well documented, and which deal with damage to the areas of the
prefrontal cortex. This brain area, it will be remembered, has
been suggested both in the literature and in my own model as an
important center involved with the working memory and with the
most complex levels of associative processing by the cortex. Such
association might be expected to facilitate complex cognitive
phenomena such as the expression of personality traits, decision
making and attention, voluntary action and free will, the
perception of and reaction to complex social situations, i.e.,
the most complex and human of cognitive functions. (It is the
frontal lobe, and especially the prefrontal area that has seen
such a massive expansion and development in the recent evolution
of the hominids.) Remember also that it is from the prefrontal
cortex that the sole cortical projection to the locus coeruleus
occurs. Projections from the prefrontal cortex also extend to the
raphe nuclei and the amygdala.
The model I have devised would therefore predict
that disruption of frontal lobe integrity should produce
alteration of salience detection and the evaluation and
expression of emotion, and radical changes in the assembly and
use of habit routines, especially as they apply to these most
advanced cognitive and affective functions. Since the connections
to the locus coeruleus, raphe nuclei, and amygdala hypothesized
to be important in my model project from the prefrontal cortex,
interference with salience and valence functions should certainly
be observed in cases of prefrontal damage. And prefrontal damage
resulting in an impaired function of working memory in supplying
parameters for the ongoing habit routine search process should
produce symptoms identifiable as resulting from impaired
generation, access to, or use of habit routine in ongoing
cognitive operations.
A very famous case of brain injury in the
prefrontal area, recently the subject of a book and various
newspaper articles, is that of the construction foreman Phineas
P. Gage. In 1848 Gage sustained a massive brain injury when an
explosives procedure went terribly wrong and sent an iron tamping
bar vertically through the frontal region of his brain.
Miraculously, Gage seemed at first practically unaffected, even
walking some distance, and conversing with his men on the way to
medical attention. It was only later that the peculiar kind of
mental deficits that necessarily result from this type of
prefrontal injury came to light. The case has recently become the
subject of detailed attention thanks to the work of Hanna
Damasio, who was able to reconstruct the precise location of
Gage's brain damage using state-of-the-art computer techniques to
analyze the features of Gage's skull, a museum exhibit at the
Harvard Medical School Museum for over a hundred years. An
overview of this work together with a detailed examination of the
symptomatic evidence in the case is presented in a recent book. (29)
It was said of Gage that he became a different
man, his entire personality was radically changed. It seemed that
he had completely lost access to his previously acquired social
conventions and rules and had become childish, irresponsible, yet
strangely undiminished in terms of episodic and autobiographical
memory, language ability, even, one might say, intelligence. In
terms of the habit routine model: In the daily yet complex social
relationships in which personality is expressed, it appeared that
Gage's behavior was capricious, or even random, the habit
routines of personality which are among the most complex and
highly associative aspects of the habit routine complex, were no
longer accessible (reconstructible) from the memory of the
frontal cortex and by consequence, his automatic social behavior
was based not upon previous experience but was instead arbitrary
and random rather than merely childish. In theory, it seems,
he could still reason out how one should act in a given
situation, but when forced into a decision by a life situation,
he was essentially powerless to apply such reasoning. This may
illustrate how dependent we are on habit routine for making
decisions and for the expression of personality. In the case of
personality traits, it would obviously be impossible to calculate
logically and consciously how to react to a situation in accord
with our established personality. The reaction must be automatic
and instantaneous. If this is also the case with at least some
aspects of decision making, a statement I previously made becomes
even more pertinent: "We see what we have already
seen..." and decide in ways that we have previously decided
to an overwhelming degree.
The symptoms described by Antonio Damasio (30) could well be
explained in these terms, but in addition, Damasio describes the
case of a prefrontal patient which he had himself examined in
detail. The patient, referred to as Elliot, had undergone surgery
for the removal of a tumor at the base of the frontal cortex,
just above the eye sockets. Surrounding brain tissue had also
been removed or damaged, and thus a large portion of the
prefrontal cortices were dysfunctional. As with Gage, the largest
part of the damage was in the ventromedial (lower-central) area,
and many of the symptoms were repeated, such as radical
personality change. But particularly striking were symptoms that
might be interpreted as resulting from interference with the
salience and valence systems involving connections from the
damaged prefrontal region to the locus coeruleus, raphe nuclei,
and to the amygdala. These symptoms might be categorized as a
lack of ability to plan ahead, to make decisions concerning
strategy and the immediate future, almost, one might say, a
deficit of free will. The obvious intelligence which Elliot
retained could not be mustered to organize even simple sequences
of activity as required for his job, for instance. In addition,
he exhibited an emotional flatness or detachment in striking
contrast to his pre-operative character.
Interestingly, a lengthy series of psychological
tests indicated that, like Gage, Elliot could theoretically make
such decisions, such as those pertaining to moral judgments, ends
and means problem solving, awareness of consequences concerning
both events and social situations, etc. But when a real life
situation forced a decision based on habit routine, the
theoretical knowledge seemed impossible to apply. In the
theoretical situation, we could say that the records of social
information in memory were actively and intentionally used to reconstruct
the required decision from scratch, whereas in the life
situation what was required was an automatic referral to the
habit routines representing such decisions that had been made
over a lifetime: the records of previous decisions as represented
in the highest levels of habit routine had been destroyed along
with frontal cortex, (31)
whereas the previous memories themselves upon which the previous
decisions had been based were still intact in other areas of the
cortex.
The combination of decision deficit with
emotional flatness led Damasio to construct a model he calls the
Somatic-Marker Hypothesis, and it has attracted much favorable
comment. (32) I
will not describe it here, but will instead offer my own
interpretation of the concurrence of the two symptoms. We could
describe an inability to make rational decisions not only as due
to deficits in the assembly of the highest levels of the habit
routine complex, but also on the basis of faulty salience
detection, since the relative significance of events and aspects
of reality, both present and in memory, must obviously play an
important role in constructing plans based upon contingencies and
the evaluation of probabilities and strategies. With both of the
above cases, Gage and Elliot, there was a theoretical ability to
make decisions, based upon reasoning processes utilizing episodic
and autobiographical memory of events themselves. Likewise,
reasoning processes and memory would be able to deduce
significance both in the internal and external environments, but
the automation of salience detection would be deficient. The key
to understanding the overall syndrome, however, is seeing that
the generation of emotional content by a holoprojection driven by
the amygdala must be a process based on information in the
salience detection holoprojection. It is with the various
significances detected in the external and internal environment
that emotional expression deals, all routine and superfluous
information merely falls by the wayside and is ignored. The SD
holoprojection feedback to all areas of the cortex accomplishes
this cancellation or ignorance of irrelevancy, to leave the
detected significances in stark contrast relative to the
background. From this holoprojection of detected significance
comes the data from which the emotional value or valence is
generated.
It is easy to see, then, that if the salience
detection system is perturbed or interrupted, a naturally
resulting symptom should be emotional flatness, or even randomly
expressed emotion since the amygdala is not itself damaged but
merely has little or no accurate information to work with. Elliot
himself realized perfectly well not only his inabilities in
making decisions in the face of real-life situations, but also
how subjects or situations that had once caused him strong
emotion no longer evoked any reaction whatsoever. Here we can see
that, since he remembers subjects which formerly caused an
emotional reaction, he can also theoretically evaluate emotional
content just as he can theoretically evaluate significance,
reconstructing the information from long-term memory. But it is
the automated accomplishment of these functions which has been
perturbed, and in real-life, on-the-spot decision making,
reconstruction does not and cannot substitute for the automated
processes.
According to Damasio's hypothesis, the deficit
for decision is based on the deficit of emotional content, but I
believe the situation is quite the reverse, that emotion is based
on significance detection necessary in the process of automatic
decision-making, and that both of these functions are based upon
intact operation and connections of the prefrontal cortices to
the locus coeruleus and the raphe nuclei.
Now I cannot tell from Damasio's descriptions
whether the actual connections projecting from the frontal cortex
to the locus coeruleus, amygdala and raphe nuclei were damaged or
severed during Elliot's operation. It would seem in Gage's case
that the trajectory of the iron bar might well indicate that
these connections were destroyed: they are grouped together into
the medial forebrain bundle, an important nerve pathway passing
directly through the ventromedial area. This pathway also
contains the projections returning from the locus coeruleus and
raphe nuclei which connect to all areas of the cortex. Whether
the severing of the medial forebrain bundle alone produces a
syndrome similar to the actual destruction of prefrontal cortex
is not known, but if my hypothesis is correct, the severing of
the medial forebrain bundle connections to the locus coeruleus
and raphe nuclei should produce a very similar result as is seen
in cases such as Gage and Elliot. Damage to the frontal cortices
may have to be quite widespread to bring about the same result as
the simple severing of these nervous pathways.
There is another type of damage to the frontal
cortex which produces rather different results. So far, in the
two cases mentioned, the principal damage was to the ventromedial
areas, just above the eyes and centrally located. When damage to
the dorsolateral areas also occurs, psychological tests indicate
an important deficit in working memory accompanies the syndrome.
These same tests, given to Elliot, showed no disability
whatsoever in his working memory function. Inasmuch as the
working memory has been proposed here as an important part of the
process of habit routine search, its disruption should alter the
process in certain ways. In the cases of ventromedial damage
cited above, I proposed that the actual memory information
necessary for construction of the highest associative levels of
the habit routine complex had been destroyed. But with
dorsolateral damage as well, an important part of the system
which carries out the habit routine search is destroyed: the
ability to supply parameters for the search is impeded.
It was proposed that conscious and unconscious
parameters guiding the successive scans producing the habit
routine complex were introduced via the working memory. The ILN
scan, incorporating WM parameters would, on the succeeding scan
retrieve a modified selection of memory information according to
the parameters previously scanned. And it was proposed that this
"small window on reality" was essentially the only
normal way to guide the processes of thinking1 using free will or
intentional creativity. In experimental situations we notice
deficits in precisely these domains. Fuster, in his book on the
prefrontal cortex, states that "In general terms, ablation
studies indicate that the cortex of the dorsal and lateral
prefrontal surface is primarily involved in cognitive aspects of
behavior. The rest of the prefrontal cortex, medial and ventral,
appears to be mostly involved in affective and motivational
functions..." (33)
(such as salience detection and emotional evaluation.)
In human prefrontal patients, a striking
experimental demonstration of working memory disruption due to
dorsolateral damage is the Wisconsin Card Sorting Test, here
described by Dudai:
The subject is presented with a series of stimulus cards
and a deck of response cards. The cards bear coloured
geometric patterns (e.g. a single blue star, three red
circles), and can be matched by categories (e.g. colour,
form, number). The examiner selects a sorting category (e.g.
colour), but does not inform the subject. The latter is
instructed to place a response card in front of a stimulus
card, wherever he or she thinks it should go. The examiner
then informs the subject if the response was right or wrong,
and the subject uses this information to obtain correct
responses in the following matches. After ten consecutive
responses, the examiner shifts the sorting category without
warning, and the subject must unveil it again to obtain
correct matches. The procedure is then repeated with other
sorting categories. Patients with prefrontal lesions find
this task abnormally difficult. The interpretation is that
they have difficulties in using temporarily stored
information to regulate their actions. (34)
The function of working memory as a parameter
store for ongoing habit routine search is well illustrated by the
experiment. The original instructions for the experiment, which
the subject has little difficulty in following, create a simple
habit routine for performing the sorting according to the first
learned category. But when the category is changed, the habit
routine developed for the experiment remains fixed, its
alteration by new working memory parameters is difficult if not
impossible. Most prefrontal patients with dorsolateral damage
have great difficulty in this test, but Elliot, whose damage was
limited to ventromedial areas, passed it with flying colors.
Now the evidence concerning prefrontal damage
and its interpretation using my model takes on some additional
relevance in consideration of the following experimental
findings: In a series of experiments using PET brain scan
techniques to observe subjects in altered states of consciousness
brought about by psychedelics, the primary effect noted was a
significant increase in the activity of the frontal cortices. (35) This result, in
combination with Aghajanian's findings of greatly increased locus
coeruleus activity caused by psychedelic drugs, lends my
interpretation some credibility. Under the influence of
psychedelic drugs, the cognitive functions of working memory and
habit routine search, significance detection and emotional value
detection are all working overtime, and they all are facilitated
by the prefrontal cortices. Whether this is all mere coincidence,
or an indication that pieces of a very intricate puzzle are
falling into place only time and further research will tell.
A vast quantity of experimental evidence awaits
the organizing ability of some yet-to-be-discovered overall model
of brain function. In reading the many papers dealing with just
the prefrontal cortex in the recently published The Cognitive
Neurosciences (36)
for example, one is immediately impressed with both the wealth of
experimental information available and the corresponding wealth
of models, terminologies, and hypotheses which attempt to
organize this information. But such a cornucopia of viewpoints
must certainly be a sign that we modelers are very much like the
collection of blind men describing the elephant from the feel of
merely local areas of the overall beast. Who will be the
visionary to discover the viewpoint from which all these models
and observations become a united whole? I certainly cannot
pretend that the cognitive and neurological models I have
presented here fulfill that function. I would be the first to
admit the highly speculative nature of the above neurological
model that I have presented, and would not be surprised nor
indignant if it were said that the area that I was describing was
not even part of the elephant!
In my view, the only claim for consideration of
my ideas stems from their origin in the attempt to explain the
body of evidence that has accumulated concerning the psychedelic
experience, evidence which has been almost entirely disregarded
by the mainstream of science for nearly thirty years. Had it not
been for such neglect, which in part was forced by an idiotic
international effort to fight an unwinnable, self-defeating and
therefore irrational "war on drugs", it seems to me
that several fields of study of human psychology and neuroscience
would have by now achieved far greater insight than is the case.
But we can blame not only the drug warriors, the
politicians and intelligence organizations, the religious
moralizers and puritanical oafs for this ignorance: scientists
too are to blame, perhaps equally so. It was easy for me, from
the outside of the scientific establishment, to see that one of
the most important discoveries ever made by Western science was
being ignored, even vilified. But from the inside of that
scientific enterprise, it was apparently no easier to see what
was happening than it was for those inside the traps of religious
fanaticism or the carefully cultivated paranoia which is the
paradigm for institutions providing much of the raw material for
the politicians: the intelligence organizations.
Scientists, at least outside the realm of their
own specialties, often seem as prone to narrow-mindedness as are
other intelligent yet confused men. It seems to be almost
instinctual that men follow such narrow pathways through life,
and the habit-routine model is certainly also an attempt to show
how such narrowness might actually be derived from an inherent
neurological feature of the human organism, rather than something
which we must label instinctual for want of a better
understanding. The functioning of our nervous systems utilizing
the habit routine system might be taken as a convenient excuse
for the current deplorable state of civilization, this
"century of holocaust," but now that I have laid bare
the roots of the situation, it is a lame excuse at best. In the
next chapter I will explore the idea that this inherent
neurological and cognitive feature has been an essential (yet now
for man a skeuomorphic or vestigial) characteristic in the stages
of evolution not only of man, but of all animal life.
References
(1) Rupert Sheldrake, The Presence
of the Past, 1988, William Collins, publisher. (back)
(2) A brief but concise description of the Hopfield Network
may be found in Crick, The Astonishing Hypothesis, ibid.,
pp182-185. A more technical and thorough exposition is found in
Churchland & Sejnowski, The Computational Brain 1993
MIT Press, p82ff. (back)
(3) Steven Rose, The Making of Memory, Bantam Press
(Great Britain) 1992, see chapter 13. (back)
(4) Ibid., p322. (back)
(5) Karl H. Pribram, Languages of the Brain, 1971
Brandon House, New York, recently reissued (1988). See also his
essay "What the Fuss is All About", in The
Holographic Paradigm, Ken Wilber (ed.), New Science Library,
Shambala 1982. Other articles in this volume discuss the
possibilities and limitations of the model. (back)
(6) "From Metaphors to Models: the Use of Analogy in
Neuropsychology", Karl H. Pribram in Metaphors in the
History of Psychology, David e. Leary, ed., 1990, Cambridge
University Press. (back)
(7) Sometimes called the "grandmother cell" model,
in which a unit of learning or recognition (of your grandmother,
for instance) was supposedly associated with a single brain cell
or strictly local set of interconnections between cells. (back)
(8) Francis Crick (1994) ibid. p185. (back)
(9) Introduced by George Leonard to refer to entities having
the nature of a hologram, The Silent Pulse, Dutton, New
York 1978. (back)
(10) "Spectral Density Maps of Receptive Fields in the
Rat's Somatosensory Cortex" in Origins: Brain & Self
Organization, Karl Pribram, ed., 1994, Lawrence Erlbaum
Associates. (back)
(11) Brain and Perception: Holonomy and Structure in
Figural Processing, Karl H. Pribram, 1991, Lawrence Erlbaum
Associates. (back)
(12) Times Literary Supplement, London, August 25,
1995. (back)
(13) See "Quantum Coherence in Microtubules" by
Stuart R. Hameroff, Journal of Consciousness Studies 1,
No.1, 1994 pp91-118. (back)
(14) In the brain there are approximately 1011 neurons
(100,000,000,000), 1015 synapses, but Hameroff estimates that
there may be 1023 dynamic sites or states associated with the
microtubules. (back)
(15) See "Perception as an Oneiric-like State Modulated
by the Senses", Llinás and Ribary, in Large-Scale
Neuronal Theories of the Brain, 1994, MIT Press. On page 113
is a summary of brain connectivity illustrative of the inadequacy
of current "information-flow" models. (back)
(16) In producing a holographic image by illuminating a
holographic photographic plate (the hologram) with coherent
light, the same image is produced by directing the light through
only a small part of the plate as is produced by illuminating the
entire plate. But the image in the former case carries much less
definition, it is of lower resolution. (back)
(17) A review of the experiments is in Human Memory,
Theory and Practice, Alan Baddeley pp14-18. (back)
(18) See "Perception as an Oneiric-like State Modulated
by the Senses", Llinás and Ribary, in Large-Scale
Neuronal Theories of the Brain, 1994, MIT Press. (back)
(19) I might go so far as to suggest that most, if not all
cognitive functions of the brain are accomplished by a dialog
among two or more brain parts, and not by a single area acting
alone to effect some cognitive result which is then passed on to
another area. The multiple holoprojection model is entirely in
accord with this suggestion. The model has conceptual
similarities to another important "checks and balances"
feedback system of the body, the hormonal system. (back)
(20) A publication containing the most recent research
findings of the important workers in this field is 50 Years of
LSD: Current Status and Perspectives of Hallucinogens, Pletscher
and Ladewig, editors, Parthenon Publishing, 1994. The book
presents papers submitted to a symposium of the Swiss Academy of
Medical Sciences in October 1993. (back)
(21) Ibid., "LSD and phenethylamine
hallucinogens: common sites of neuronal action", G.K.
Aghajanian. (back)
(22) Another way of thinking about the disparity between
"input" and "output" signals again
illustrates a basic conceptual fault with the computer model of
brain function. In the case of the locus coeruleus for example,
it has been stated that since its "output" extends to
such diverse regions, its functions must also be multiple and
widespread. This view has the underlying assumption that the
locus coeruleus is sending information it has processed from its
modest input, to many locations where this data is then used for
many different functions. But the alternative view I have
proposed is that the locus coeruleus accomplishes only one
function. The multiple and widely connected "output"
pathways are not to be seen as sending information, but rather as
requesting or accessing information of a widely diverse
nature (relating to the detection of salience in many domains,
situations, and complexities). The result of this request is then
cycled back to the locus coeruleus via its modest input from the
frontal cortex, as a reverberating holoprojection. (back)
(23) Ibid, p27. (back)
(24) Chemoarchitecture of the Brain, Rudolf
Nieuwenhuys, 1985 Springer-Verlag, p40. (back)
(25) From references mentioned in Stairway to the Mind,
Alwyn Scott, Springer-Verlag 1995, p94. (back)
(26) A suggestion of Donald Hebb, recounted in Stairway to
the Mind, ibid., p94. (back)
(27) "The New Alchemy" in This Is It, Alan
Watts, Random House, 1958. (back)
(28) Aghajanian in 50 Years of LSD, ibid., pp33-34 (back)
(29) Descartes' Error, Antonio R. Damasio, G.P.
Putnam's Sons, 1994, chapters 1 & 2.
(back)
(30) Ibid. (back)
(31) One could view the situation also as an inability of the
intralaminar nucleus of the thalamus to include in its habit
routine-generating scan the information from the destroyed
frontal region. This is probably the more useful if not accurate
view, as opposed to the view that frontal lobe
"information" has been destroyed.
(back)
(32) Ibid., p173-ff. (back)
(33) The Prefrontal Cortex, Joaquin M. Fuster, 2nd
edition 1989, New York: Raven Press, p74.
(back)
(34) The Neurobiology of Memory, Yadin Dudai, Oxford
University Press 1989, p263. (back)
(35) F. X. Vollenweider and colleagues in recent papers
summarized in "Evidence for a cortical-subcortical imbalance
of sensory information processing during altered states of
consciousness using positron emission tomography and
[18F]fluorodeoxyglucose" in 50 Years of LSD, ibid., pp67-86. (back)
(36) Michael S. Gazzaniga, editor, The Cognitive
Neurosciences, 1995 The MIT Press. (back)
(note) Update to the 1996 edition of The Center of the Universe: The proposal that background neural activity is not mere random noise is supported by recent findings indicating that background neuron firing is fractal in nature. In the Journal of Neuroscience (vol 17, p 5666) Malvin Teich of Boston University notes that the average release rate [of neurotransmitter packets] fluctuates as dramatically from minute to minute as from second to second. Such repetition at different scales is a hallmark of fractals. (Quotation from New Scientist, 16 August, 1997.)(back)
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