Nature of Consciousness
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Perhaps no problem has proven more vexing
to both philosophical and scientific scholars than an account of the nature
of consciousness. The reflective nature of consciousness—its ability
to consider itself, to provide a sense of being—has led some philosophers
to assume that it characterizes the very essence of what it means to be
human. Or in the words of Descartes:
Cogito ergo sum
This sense captures only one
of a number of meanings that have come to characterize consciousness in
contemporary times. Modern psychological views of consciousness originate
in William James classic work, Principles of Psychology (1890).
Most of the qualities he ascribes are easily discovered through introspection—a
somewhat undifferentiated view of consciousness relative to more contemporary
accounts. They are presented below:
Every thought tends to be part of a personal consciousness.
Within each personal consciousness thought is always changing.
Within each personal consciousness thought is sensibly
It always appears to deal with objects independent of
It is interested in some parts of these objects to theexclusion
of others and welcomes or rejects—chooses from among them, in a
word—all the while.
One of the problems with
contemporary accounts is that consciousness is defined in terms of a number
of different activities of the mind. Philosophical, information theoretic,
and neuroscientific approaches often use consciousness to mean different
things. Simply note the difference between using "conscious" to mean
awake (not comatose), to be aware (I was conscious of a really strange
smell in the room), some existential state (I suddenly became conscious
of the meaning of my life and my place in the universe). Pinker (1998),
has identified these different usages in How the Mind Works and
also the relative success of scientific explanations for these usages.
He suggest at least three ways in which the term consciousness is used:
2. Access to
The sense of self as an entity. Not only am I seeing
red, I am aware the it's me, Dr. Fred who is seeing red. Here consciousness
is defined as building an internal representation of the world that includes
the self. This is the sense in which the term is most frequently
used academically by cognitive scientists.
When defined in this way, cognitive science provides a
fairly good account of the nature of consciousness in terms of an internal
representation of the self including self-monitoring. Further, this
account is easily modeled in computer programs that can examine, report
on, and modify themselves on the basis of available information.
This definition of consciousness relates to the ability
to verbalize sensory experience, the contents of memory and thinking.
Roughly equivalent to what we call awareness or what cognitive scientists
call short term memory
There are clearly two pools of information that the nervous
system uses to process information—that which is immediately available
to the systems that underlie verbal reports, rational thought, and decision
making—and that which is not. Some information in the latter is never
available such as autonomic nervous system functions and the calculations
that the nervous system uses in processing (e.g., the use of information
about retinal disparity in providing the experience of visual depth).
Other information not immediately available can move into awareness and
visa versa—one's knowledge data base and long term memory are examples
of the latter.
Any information processor must be given limited access
because information has costs as well as benefits (space or storage capacity,
There are four very obvious features to access consciousness:
We are aware of a rich field of sensation and further,
the contents of this awareness are at an intermediate level of integration—we
are unaware of the lower level processing that's going on. Objects
come to us already integrated as meaningful entities with some perceptual
constancy (the piece of coal in the sun, snowball indoors example).
What we perceive is a highly processed product—a scene in vision, a melody
in audition, meaningful words in language, not patches of light or sequences
of sound pitch.
A second feature is attention—there are limitations on
the amount of information that we can process at any given time.
Attention is like a spotlight that brings certain information into consciousness.
Interestingly, since the brain is a parallel processing device, processing
can and does occur outside of awareness. Many of the skilled tasks
you now perform automatically, without "thinking," originally required
very focussed attention. (Driving a car, keyboarding, riding a bike
to name a few.)
Thirdly, the contents of access consciousness are emotionally
colored. This fact is evidence of the functional evolution of mind—it
evolved for some purpose. Motivation and emotion is the motor moving
the organism to some end. The mind and consciousness did not come
into being because they were neat things to have, but rather because they
contributed to the survival and consequently the procreation of the organism.
Finally, access consciousness features an executive function
that makes decisions and choices—something we experience as the self, the
will, the "I." The executive demonstrates intention (in the philosophical
sense) in directing the body, the senses, the mind, etc.
This sense of consciousness is the one used most by philosophers
and theologians—phenomenal awareness, subjective experience—the sense of
being in the world. The sense of "I am."
It is this sense of consciousness that cognitive science,
or any science, has difficulty explaining. But does it require an
Pinker (1998), in the section of the assigned reading
on consciousness, suggests (particularly in the questions he poses in that
section) that sentience is an emergent property of the information processing
He cites the work of Dennett and other functionalists
who believe that once we have isolated the computational and neurological
correlates of access consciousness, there is nothing left to explain.
In this context, sentience is viewed as an "epiphonomenon"—a side effect
of information processing systems coming together to produce access consciousness.
While giving an account of sentience may be an interesting philosophical
exercise, it neither adds to nor detracts from our understanding of how
the mind works
Trying to answer the questions he poses in the
section on sentience is a valuable exercise and will serve to sharpen your
own understanding and views of these issues. Good luck!!
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