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If
we compare the brain to computer hardware, the states of consciousness
represent its operating programs. These are no more than patterns for
the processing of data, and can only work if they are compatible with
a basic language which, in turn, is a code capable of organising the
data supplied by the individual programs. Within the structure of consciousness,
the basic language can be viewed as the ancestral memory, holding remembrances
of the individual sensations or of the single basic operating schemes,
based on which it has been possible to learn the language and build
an "interior model of the physical world".
Although
approximate, and therefore inaccurate, as are all the technological
metaphors which attempt to describe biological structures, nevertheless
this comparison is certainly useful to understand a subject, that is
consciousness, which in the last fifty years has forcefully imposed
itself on the attention of neurobiologists.
This
interest can be said to have began in the forties, when Albert Hofmann,
in the Roche laboratories, in Switzerland, discovered and synthesized
the lysergic acid diethylamide, which subsequently became very well
known by the acronym LSD. Till then, consciousness had only been a field
of philosophical speculation and a subject of little interest for psychology.
LSD
suddenly disclosed extraordinary connections between the neuronal hardware
and the mental software, thus suggesting that consciousness is somehow
a product of the activity of neurons and of chemical relations set up
among them. The neuroscientific importance of consciousness, of its
structure and of its modified states, had already been amply perceived
during the last century by the Salpetrière clinicians, by the school
of Jean Marie Charcot, by the founder of psychoanalysis, Sigmund Freud,
by a number of experimental psychologists like William James and, above
all, by Pierre Janet.
Somehow,
with the success and the diffusion of the psychoanalytic theory, it
appeared that the unconscious was more significant than consciousness,
and the latter subject faded into the background. Undoubtedly, the initial
interest arose because Charcot and all his followers (including Freud)
used and practised hypnosis, a condition which today could be defined
as the chief of many modified states of consciousness ("modified" sounds
much better than "altered", as one often reads; and besides, the English
word "altered" is the exact translation of the Italian word "modificati");
this is why they had been in some way forced to direct their attention
to the structure of consciousness in order to understand the modifications
experienced in a state of trance.
Anyhow Charcot was a clinician, essentially interested in the pathogenesis
of diseases, and although he was able to reproduce the symptoms of a
neurosis by putting his patients into a state of trance, he was never
able to demonstrate the causal connections between the modifications
of the state of consciousness and the pathogenesis of neuroses. However,
the great interest for this aspect was shared by all those who attended
his famous "Tuesday lectures" and, amongst all, the person who succeeded
in constructing a satisfactory aetiological theory of neuroses was Freud,
with his concept of "pathogenic unconscious" which, although weakened
nowadays, has not yet been replaced by a more valid theory. Even though
they spent the rest of their carriers working on the ideas of their
master, the other followers of Charcot have either been forgotten or
are now remembered for other merits.
Babinski, for instance, is known for his "sign" (extension of the hallux
as a reaction to friction on the side of the foot) rather than for the
fact that he (rightly) supported the idea that hysteric neurosis is
a psychiatric disorder and not a neurological syndrome (as Charcot had
claimed for years).
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