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Osama Almughrabi
Evan Fletcher
The Study of Consciousness
12/08/06
The Origins and Function of Self Through an Understanding of Neuroscience: Bundle
Theories and Ego Theories
In investigating the self, we are presented with numerous questions on its origins
in the brain. Can it be tied into specific brain system? What is its relation to
consciousness; is it encompassed by, outside of, or equal to consciousness? Different
neuroscientists define the self in their own ways, particularly in the manner in which they
divide the concept. These groupings are either theoretical, that is to say they are
artificially created to facilitate investigation, or they are functioning groups that work
together to form the self. Neuroscience points to mental representations or “neural maps”
to explain the function of self as an observer. The idea that there is a single observer who
experiences life is known as an “ego theory”, while the idea that there is no unified self is
termed “bundle theory”. Although the reader will not be left with any sense of complete
understanding, and no ultimate conclusion has yet been presented by science, the
concepts are material for internal inquiry and are highly thought provoking and
controversial. Investigation into the subject is severely complicated by the subjectivity of
human experience. The self is thoroughly personal.
Since René Descartes’ famous assertion following his foray into reductionism, the
existence of the self has been considered by many to be the only guaranteed truth that the
world has to offer. Cogito, ergo sum (in latin), or je pense, donc je suis (in its original
French) is not, however, the only philosophy on the concept of self. Descartes reached
his conclusion by doubting everything that had been presented as truth to find that even if
his mind was being deceived about every aspect of his existence, the only thing that he
could be sure of was that there was a being (himself) that was being deceived. If every
other fact and sensation was a lie, the fact that he existed and sensed was still true.
Conversely, the teachings of the Buddha, believed by many people the world
around, say that there is no self. In Buddhism, there is sensation and thought, but no
actual observer - only the illusion of an observer. Both concepts of the self find their way
into the realm of neuroscience. The two types of theories can be divided into “ego
theories” and “bundle theories” (Parfit 1987) with the former corresponding to Descartes
and the latter to the Buddha. Ego theory says there is a single self, while Bundle theory
believes that there is no one self but a “bundle of sensations” (Hume 1734). Oddly
enough, neuroscience has not lent itself entirely into one category or the other, but still
straddles the two.
Those major religions that believe in a soul fall under the “ego theory” category.
They are a form of substance dualism and believe that there is a unified self that watches
or controls the actions of the body and will one day leave the body but continue to exist
without it. The basic materialist would also fall under the category of ego theory, or so
one would assume. The materialist believes that consciousness is entirely the result of
brain firings, but if he believes in the value of qualia he is likely to believe that there is a
unified self that is experiences those qualia. It can (or will soon) be located and
understood. Francis Crick’s reversal from his Astonishing Hypothesis (that
consciousness is the result of brain activity) (Crick 1994) to then deciding in his work
with Koch that the consciousness can be broken down into Neural Correlates of
Consciousness (Crick, Koch 1990) illustrates a discrepancy. The concept that
consciousness is integral to brain function and does not exist in some alternate nonphysical realm is directly related to ego theory. However, the leading neuroscientists
studying consciousness are focusing on breaking down the components of consciousness,
including Crick and Koch with their NCCs, Antonio R. Damasio’s first- and second-order
representations, and Edelman and Tononi’s theories on diversity and uniformity (Tononi
and Edelman 1998). Daniel C. Dennett falls outside of this grouping, because although
he is a definitive reductive materialist, he maintains that there is no self and that qualia
are illusory. Dennett is a bundle theorist.
And he is in good company. The famous philosopher William James was a
bundle theorist in that he also dismissed the existence of a unified self. He instead
explains self-awareness through “the Thought”. To James, this “thought is itself the
thinker” (James 1890) and in each passing moment envelopes the previous thought,
discarding some portions while absorbing others. The relation to Buddhism is uncanny.
We will see that neuroscience fully accepts neither ego nor bundle theory but holds its
own sort of superposition on the subject.
Antonio R. Damasio explains his approach in terms of a “movie in the brain”.
That there is one conscious self that is viewing the movie shows his ego theory and
reflects the Cartesian theatre of Descartes. The “self” is actually a sense of ownership
over the movie and the movie is the result of the individual’s brain creating a
representation of external and internal activity. Every aspect of this process is biological
and relates to specific regions of the brain that will soon be understood in their entirety.
To Damasio, an understanding of self is critical to an understanding of consciousness as a
whole. The self, as he explains, is nestled within the consciousness. Since that sense of
self exists inside the movie as well, representations of the self must combine with
external representation.
The purpose of this sense of ownership is evolutionary. There is an added
incentive to continue living if an organism holds ownership over its body and its
thoughts. Since the brain already maps the body’s internal function in order to regulate
it, the transition over to a sense of ownership would be easily accomplished. The internal
mechanism is explained by his first- and second-order representations. The first order
does the internal monitoring and regulation of bodily function by creating diagrams of the
body’s functions. The second-order monitors changes in the first-order, effectively
watching the watching system. Each time it notes a change the person becomes aware of
a pulse of consciousness.
Damasio next partitions both the self and memory into several divisions - here he
further deviates from ego theory. First comes the Protoself, which is not actually part of
the conscious self but rather the non-conscious basis of the self. Consciousness can be
divided, according to Damasio, into “core consciousness” and “extended consciousness”.
Core consciousness is a sense of self, but only in a limited and immediate sense. It bears
no connection to time. It is developed by a division of self, the “core self”, the
continually re-created self that exists in the moment. Extended consciousness being more
varied and elaborate, provides for identity, and would thus be more analogous to selfawareness. It borrows from the “autobiographical self”, which is the collection of facts
and figures about the individual that he characterizes himself by.
Similar divisions can be found in the work of Gerald M. Edelman and Giulio
Tononi. In their work, the division of consciousness is still two-fold, with the first
underlying level being “primary consciousness” and the more involved being “higherorder consciousness”. In both Damasio and Edelman and Tononi’s works the lower, less
elaborate level is prerequisite for the higher level. Edelman and Tononi interestingly
make mention of their speculation that other animal forms are capable of primary
consciousness, but that humans seem to be alone in their use of higher-order
consciousness. Again, as with Damasio, it is the aspect of the placement of self into an
understanding of the world that differentiates the types of consciousness. Primary
consciousness and Damasio’s core consciousness illustrate that the organism is placing
itself into its mental representations. In higher-order consciousness and extended
consciousness, the organism (human) places its self-representation into other theoretical,
non-immediate timeframes, locations or situations while in a waking state. Edelman and
Tononi note additionally that linguistic capabilities are the realm of the higher-order
consciousness. Unlike Damasio, Edelmen and Tononi suggest that the self simply
accompanies higher-consciousness – that self is more of a byproduct of consciousness
than an integral part of it.
The (otherwise) similarity between Damsio’s work and Edelman and Tononi
extends into their descriptions of what brain regions serve to form the higher-order
mapping or awareness. Damasio lists (without further elaboration) the parabrachal nuclei
and periductal gray as key components of the Protoself (which you will remember is
related to core consciousness an first-order mapping, where there is no self-awareness).
As far as second-order mapping, he indicates the importance of the thalamus as well as
numerous cortices (cingulated, prefrontal, and those that associate between the medial
and parietal lobes). Edelman and Tononi also point to the thalamus and the overall
cerebral cortex for the reason that reduced blood flow to these regions can be observed
during unconscious states of sleep. The thalamus is believed to serve as a relay of
information to the cortex. For Damasio, who believes that the self exists inside of
consciousness, this may be sufficient, but for Edelman and Tononi, who say that the self
is a result of consciousness, the question of location of the self still remains.
Joseph LeDoux is yet another published neuroscientist who believes that the self
is the key to unlocking the mystery of consciousness. One aspect that LeDoux discuses
that his colleagues do not focus upon is the question over when in the human’s lifetime
the self is manifested or develops. Stepping beyond the intentional obscurity of
definitions of the self (seen in Edelman and Tononi) LeDoux tells us that he shares
James’ view on the self as the sum of who one is. He further mentions that it
encompasses, but is not limited to, the owner’s personality. As far the development of
this “sum total”, a further parallel can be drawn to James with LeDoux’s assertion that
“[t]he self is not static” (LeDoux 2002). With that said, how much does the summation
depend on genetics? How much on environment? How much on memory?
In Synaptic Self, LeDoux traces the argument all the way back to the advent of
cell-theory into the theories of neuroscience, the concept that the brain consists of
discrete cells much as other biological systems. Continuing from there, he points to the
emergence of selectionism, or the concept that the neural connections that are used are
strengthened and those that are not die off. Both of these ideas are practically taken for
granted in modern science. The relevance to our investigation of the self is as follows: if
the neurons that one is to posses in adulthood develop during childhood as dictated by
genetics, it would seem that the self is predetermined. The reverse view to this
metaphorical coin-toss is the view held by child psychologists and youth-development
professionals that environment plays a major roll in the origin of the adult person. We
now have on our hands a traditional nature-versus-nurture argument. When the coin
lands on nature, the well-researched fact that neurogenesis (the growth of new neurons) is
exceedingly uncommon in adults lends to the belief that personality (self) is genetically
determined. However, life experiences clearly lead to personal mental expansion in the
form of learning and cognition. Twin studies illustrate the nature/nurture duality as well
– identical twins separated at birth may hold very different social, religious and political
views, but there will often be inexplicable idiosyncrasies and tendencies shared between
the two. According to “nativist psychologists”, this can be explained by the means with
which the brain actually retains knowledge. Far from John Locke’s vision of the mind as
a “blank slate”, nativists point to neural selectionism to explain information retention and
the formation of personality. As a youth, one is presented with all of the neurons that
will go on to form the self as well as representing all of the knowledge one will posses.
As time progresses, knowledge is achieved (stored) by the strengthening of oft-used
neural firings (“wiring by firing” as LeDoux terms it). Although “synaptogenesis” (or the
creation of new synaptic connections) does occur, it is the selectionism of the brain that is
responsible for most learning. Through the nativist theory, the self is not developed or
created by the environment – it is naturally selected. Nativists even apply this theory to
language acquisition, saying that language is an innate ability of humans needing only
contextual stimulus to bring out the latent knowledge.
LeDoux presents these views in such a way as to maintain objectivity and
disguise his sympathies. After the Nativist approach he illustrates the flip side; the
Creativist doctrine. These people maintain that “cortical plasticity” (or the manner in
which a brain system adopts its purpose given the necessities of the organisms brain
structure) rather than “cortical specificity” is responsible for learning. Creativists oppose
nativists by asserting that language stimulis is insufficient to invoke language learning.
This is particularly obvious in the proper use of grammar. Constuctivists further make
note of lesion studies in which the language centers of young people are damaged. The
youths are able to learn to speak using different brain centers that are in fact rewired.
Animal transplantation shows that brain chunks that are relocated to other portions of the
brain can take up the mental aspects of the new region it inhabits. Neither nativists nor
creativists deny the existence of the processes described by the opposite camp, but simply
interpret the data to fit their own viewpoint.
From the various, diverse, materialist views of Dennett, Damasio, Edelman and
Tononi, Crick and Koch, and LeDoux, we will briefly examine a mysterian’s thoughts on
self. Colin McGinn places the self at the center of consciousness (similar to Damasio)
but says that it is not actually a state of that consciousness. The self is rather the subject
of the states, is actually defined as the recipient of those states. This is an unadulterated
ego theory, pointing to the self as a unified observer and experiencer. McGinn
differentiates between sentience and consciousness and attribute the former alone to the
brain processes of animals. He further discriminates between consciousness and selfawareness, explaining that one can be assimilating external information without the
actual cogitation that one is performing a process of assimilation. The cogitative
awareness is equal to self.
One of McGinn’s major arguments on the impossibility to understand the origins
of consciousness hinges on our inability to explain how the self begins or ceases to exist.
This is a specifically ego theory-related problem in that the bundle theorist response to
the question would be a simple (and confoundingly Buddhist-style answer-a-questionwith-a-question) response: Does the self ever start or stop existing? “The world may
never know”, says the tootsie-pop narrator.
Clearly the scientific approach to an unanswered question is to perform an
experiment on the subject. But as is often the case in neuroscientific research, there is a
problem with measuring or quantifying the subjective nature of self-awareness. In order
to better tackle the problem, scientists have focused on various means of dividing and
subdividing consciousness or looking for its basis in other systems of the brain. Further,
it is difficult to isolate one section of the brain since they work in such close conjunction,
usually simultaneously in parallel. Thus it is often lesion studies, in which a portion of
the subjects brain is damaged or dysfunctional, that allows researchers to view in a
specific way a limited portion of the cognitive structure.
A recent study at the Santa Barbara Department of Psychology investigated D.B.,
a patient who underwent “cardiac arrest with presumed anoxic encephalopathy” and was
later found to suffer from anterograde and retrograde amnesia. Stanley B. Klein, Keith
Rozendal, and Leda Cosmides performed the study and used certain preconceptions to
determine the aims of their investigation. They wanted to research the way an individual
forms mental representations of self-knowledge. How is knowledge about your own
personality stored? Two potential answers that the team investigated were the
“computational view” and the “abstraction view”. The computational view says that a
person decides whether he or she posses any given trait by looking into our memories of
behaviors that express that trait. Conversely, the abstraction view says that the person
holds an abstract impression or summary of personal traits that is accessed in order to
make such a determination.
The team further hypothesized that there exist at least two distinct forms of
memory: episodic and semantic. Episodic memory relates to the computational view in
that access to episodic memory about ones own actions would hypothetically be required
to form the judgment over whether one held a particular trait. Semantic memory is not
directly related to any event, so it corresponds to abstraction hypothesis.
The investigation was performed with the assistance of D.B.’s daughter and with
appropriate blinds and control test subjects. D.B. was first determined to have no
episodic memory. He could not remember historical events to any sort of accuracy, nor
could he remember objects presented to him from one session to the next. The team next
tested his semantic memory. Although this somewhat better intact, D.B. scored far below
the control subjects on being able to identify personal experiences from different periods
of his own life. Neither was his semantic memory of other people intact – D.B. could not
accurately describe the personal aspects of his daughter. Finally, the investigative team
asked D.B. to describe himself. According to the comparison of his daughter’s
descriptions of him, D.B. was easily able to do this. The research team further noted that
while D.B. would become frustrated with his lack of memory on other topics, he actually
seemed to enjoy talking about his personality traits. But where did this knowledge come
from?
Since neither D.B.’s episodic nor his semantic knowledge was intact, neither the
computational hypothesis nor the abstract hypothesis was correct. D.B. seemed to be
able to know what he was like as a person without taping into previous knowledge of
either his actions or of his personality, but based it solely on some sense of self not
related to memory.
So many questions remain. If the self is not static and either develops or is
selected out of genetically pre-programmed neural substance, then how can D.B. know
what he is like as a person? How can the effects of his experiences on his personality still
be active without the memory of those experiences? Does he actually posses a unified
self, or is that self only an illusion generated by the “bundle of sensation” he experiences?
Clearly neuroscience has yet to present an explanation.
Crick, F. and Koch, C. (2003) Consciousness and Neuroscience, repreinted in Essential
Sources in the Scientific Study of Consciousness, Barr, Banks and Newman, eds.,
MIT Press.
Damasio, A. (2000) A Neurobiology of Consciousness, reprinted in Neural Correlates of
Consciousness, Thomas Metzinger, ed., MIT Press.
Dennett, D.C. (1987) The Intentional Stance. Cambridge, MA, MIT Press.
Dennett, D.C. (1991) Consciousness Explained. Boston, MA, and London, Little, Brown
and Co.
Dennett, D.C. (1995a) Darwin’s Dangerous Idea. London, Penguin.
Descartes, R. (1641) Meditations on First Philosophy. Paris, trans. 1901 by John Veitch.
Edelman, G. and Tononi, G. (2000) Reentry and the Dynamic Core, reprinted in Neural
Correlates of Consciousness, Thomas Metzinger, ed., MIT Press.
Hume, D. (1739) A Treatise on Human Nature.
James, W. (1890) The Principles of Psychology (2 volumes). London, Macmillan.
LeDoux, J. (2002) Synaptic Self: How our Brains Become Who We Are. Middlesex,
Penguin Books.
McGinn, C. (1999) The Mysterious Flame: Conscious Minds in a Material World.
New York, Basic Books.
Moffett, S. (2006) The Three-Pound Enigma. New York, Workman Publishing.
pages 190-221.
Shalom, A. (1985) The Body/Mind Conceptual Framework & the Problem of
Personal Identity: Some Theories in Philosophy, Psychoanalysis & Neurology.
Atlantic Highlands, Humanities Press International.
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