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A new phenomenon has emerged during the past decade:
frequent symposia about the nature of consciousness that bring together
a hugely multidisciplinary crowd which includes psychiatrists and
neurologists. These individuals attempt to address one of the greatest
unsolved mysteries—how consciousness arises and how it creates
the self. Dissatisfied with insufficient progress in the clinical
domain, psychiatrists and neurologists are exploring the foundations
of our discipline.
In his earlier book, Descartes’ Error, Damasio argued that
Descartes made a major mistake when he attempted to treat reason
and emotion as separate entities and set our thinking about these
issues on an inevitable collision course. The author is a neurologist
with many years of caring for patients who have various types of
brain damage, and in his follow-up to this amazing book, he investigates
the neurobiology of consciousness and of the experience of self.
In doing so, he enters a domain previously visited only by eminent
philosophers and thinkers. That it is now possible for neuroscientists
to meaningfully address such ultimate questions attests to the technological
advances of neuroscience.
With the aid of rich neurological and neuroanatomical material,
Damasio explains that there are in fact 3 different but closely
linked types of consciousness: the protoself, which is the mind’s
constant monitoring of the body’s state that takes place without
awareness; the core consciousness, which provides “the movie”
of the outside world; and the extended consciousness of cognitive
processes, reason, memory, and language. Damasio documents the clinical
material indicating that core consciousness can exist without language,
reason, or memory; that is, it can exist without extended consciousness.
For psychiatrists, the 2 particularly important points are that
emotion and consciousness tend to be present or absent together
and that the neuroanatomical system responsible for them is relatively
small, but complex, and includes the brain stem and hypothalamic
structures, the amygdala, the cingulum, and parts of prefrontal
cortex. This helps to explain many observations made in clinical
psychiatry—for example, why both depression and mania can completely
influence and overwhelm reason, memory, and perception of the external
world, as well as changing body functioning, and how the clinical
course of mood disorders arises from the oscillatory process in
the above-mentioned system. Clinical histories, presented simply
and illustrating his points crisply, are the best parts of his book.
This book both delights and challenges. Damasio has an easy writing
style, but the topics are highly abstract and the reading takes
much concentration. It takes astonishing boldness to enter where
before only eminent thinkers ventured. The text is an amazing synthesis
of precise experimentation and poetic thinking. While integrating
current neurological information and his own observations about
human consciousness, in key passages Damasio evokes TS Eliot and
Shakespeare, making good use of various metaphors to explain his
points.
Damasio’s contribution will appeal to the academically minded,
but his use of plain language and careful metaphoric explanation
of key points makes the content accessible for the general reader
as well. For a psychiatrist interested in the basic questions of
our profession and in understanding the neuroscience-based foundation
of psychiatry, this book seems to be a must.
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