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Are Animals Conscious?
A Tour Through the Issues
At a slightly higher level, we might ask whether, for instance, plants might
be aware of their environment. While, in this case, the well-being of the
plant certainly is affected by the surroundings, the plant still has no
mechanism to evaluate that well-being, so we can also say that the plant is
not conscious of its environment. Of course, the plant can implement
certain behaviors in relation to the environment, such as turning leaves
or blossoms toward a source of light or a carnivorous plant closing its leaf
upon being touched. However, there is no reason to believe that the
mechanism which does this is fundamentally any more complex than the
thermostat's action in turning on the furnace. An evaluation mechanism
is still missing. Also, we would note that any "memory" the plant might
have for environmental conditions would be limited to changes in the gross
physical form, such as a tree growing to adjust for a prevailing wind,
ie., there is no mental component of such "memories".
Invertebrates
At about this level, we begin to see the ability of the organism to
incorporate "memories", even a flatworm can "learn" to negotiate a maze.
This seems slightly less physical and more mental than the tree growing to
adapt to the wind. However, it still seems quite doubtful that this "memory"
involves in any direct way an evaluation of the sensory input as it affects
the body state.
In fact, there are convincing cases of active memory usage at these levels.
There is a type of wasp which learns its way home by landmarks. If you move
the local landmarks while the wasp is gone, it will be confused on returning
and will perform an exhaustive search of the neighborhood until it finds
the nest. What is the relation between complexity of such behaviors and
the question of mentality? Can it be argued that this behavior implies
Damasio's required level of body state processing?
Vertebrates
Mammals
Damasio makes what I believe is a very useful distinction, separating the
ideas of feelings and emotions. He considers feelings to be the organism's
internal view of various body states and conditions, while emotions are the
external display of those internal views. An emotional display thus rests
upon the organism's awareness of the feeling. Through the kinematic senses,
the organism may then become aware of having produced the emotional display,
which can produce its own feeling, leading to a second round, an
intensification of the emotional display.
We now have to be much more careful in determining the role of memory. To
the extent that the animal is capable of evaluating a recalled memory in a
way corresponding to the usual evaluation of the present moment, we would
have to say that the animal would be aware of the past. Certainly, the
animal can be trained to respond to remembered patterns. What is not clear
is the extent to which such patterns are consciously evaluated. It is
possible that even the rat is dimly aware of the present moment and the cat,
dog or horse may be able to think of memories from the past. The complexity
of a dolphin's responses would certainly seem to indicate a complex
evaluation of recalled memories.
How the World is Viewed
The astounding thing about this is the ability of the brain's sensory
processing functions to construct a coherent and consistent internal
representation of what that world is like, based on whatever inputs are
available. Humans are blind to infrared and ultraviolet light, ultrasound,
and all but the most pleasant or obnoxious smells, and yet we feel that the
world, as we sense it, is complete. We are not usually aware of the missing
pieces. This must be so for all of the animals which are conscious of their
sensory inputs, whatever the type or range of the sensory mechanisms.
The Self
Even a bird will take note of a mirror, parading and sometimes pecking at the
image. However, there seems to be no reason to believe that the bird is
reacting to itself rather than another bird. This behavior is similar up to
the level of a chimpanzee. If you paint a red spot on the forehead of a dog
or cat before introducing the mirror, the animal will paw at the mirror where
it sees the spot. The chimpanzee will reach up and touch its own forehead,
watching in the mirror as it does so.
Concepts
So what is all this about concepts? Is a concept anything more than "that
which you can conceive of"? I would only add that conceiving of something
includes to be able to do so in the absence of any external stimulus which
would represent that thing. But then why do I say that the self-image
requires a concept? What I have in mind here is that the self-image is
more than just the perception of one's own hands and feet, maybe a glimpse
of the tip of the nose or the torso. More than the sounds of the various
parts, working away. I claim that to be aware of one's self-image also
includes memories of past images and perhaps even more importantly,
memories of previously worked out future plans and how the present view
of the self and its current state fits with those past futures. It means
being able to synthesize all that into something new, which is at no point
represented by a present stimulus. It is in this sense that I claim it is
a concept.
Language
For most humans, it seems that words form a major portion of the contents
of C. (Visual images make up another large portion for most people). This
is probably even more true for non-sighted people, where sound replaces the
visual input. The mind seems intent on supplying an endless stream of
verbal commentary. Living alone, in the quiet, I have nurtured the ability
to work for long stretches at a time with the internal verbal stream shut
off. To be sure, I am surrounded by an equally endless stream of written
materials. Even the numbers on the clock face can be considered as a form of
linguistic communication. But if, for example, I go outside to set up the
lawn sprinkler, I would often complete the entire operation without
encountering a single linguistic form. I imagine this to be somewhat similar
to the experience of the chimpanzee, happily going about his daily business.
With meditative practice, it should be possible to turn off
conceptualization, making it possible to experience the C of a cat or a
mouse. A Zen master might even be able to cease the continual evaluation
of all sensory inputs, perhaps allowing the master to experience what it is
like to be an insect.
The Opposing View
One of the pieces of evidence cited by this faction is the spilt brain data
described by Gazzaniga. The argument goes that if a callosotomized patient
is completely unaware of right hemisphere activities unless they are somehow
communicated to the left hemisphere, then the entire seat of C must be in
the left hemisphere and (therefore?) language related. The facts are
certainly interesting, but, to my mind, do not justify the stated
conclusions. I can imagine some sort of inhibitory action imposed by the
dominant hemisphere, which would repress the weaker form of C as produced
by the opposite side.
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