These are excerpts and elaborations from my book "The Nature of Consciousness"
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In contrast to Jouvet,
Hobson and Winson, the US philosopher Owen Flanagan thinks that both sleep and
consciousness are products of evolution, but consciousness during sleep
(dreaming) is merely an accident of nature, a side effect of the two. Both
consciousness and sleep have a clear biological function, but dreams don't. During sleep the brain
stocks up neurotransmitters that will be used the next day. By accident, pulses
that originate from this stockpiling chore (coming from the brain stem) also
reactivate more or less random parts of memory. Unaware that the body is
actually sleeping, the sensory circuits of the cerebral cortex process these
signals as if they were coming from outside and produce a chaotic flow of
sensations. Thus we dream. Dreams are just the noise
the brain makes while working overnight. If Flanagan is correct, dreams are
meaningless and pointless. Of course, indirectly,
dreams tell us something about how our mind works, because, after all, whatever
we perceive while we dream is the product of what is in our memory and of how
our cerebral cortex processes those memories. But the usefulness of the
dream-narrative is really limited to an almost "diagnostic"
purpose. As our cerebral cortex tries
to make sense of that chaotic input, we can learn something about its cognitive
functioning, just like by running the engine of a car when it is not moving we
can learn something about a noise it makes on the freeway (but the engine
running while the car is not moving has no hidden meaning). Back to the beginning of the chapter "Dreams" | Back to the index of all chapters |
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