Philosophers who are engaged in the project of
attempting to understand the human mind increasingly turn to the neurosciences
for inspiration and information. Hirstein is one the growing number of such
philosophers who are at much at home in the neurosciences as in their home
discipline. He has himself engaged in experimental work, and published several
articles with neuroscience luminary V.S Ramachandran. In this book, he attempts
to draw philosophy and neuroscience together, in order to contribute to
understanding the mind and some of its pathologies.

The
pathology, or pathologies, with which he is concerned is confabulation.
Clinically, ‘confabulation’ is normally used to describe the manufacture of
sometimes plausible, sometimes wildly implausible, fictions, especially by
sufferers of Korsakoff’s syndrome. Korsakoff’s syndrome is characterized by
severe amnesia, affecting autobiographical memory. Sufferers are unable to form
new, lasting, memories of events.  They are therefore typically at a loss to
know what they are doing in a hospital. When they are asked where they are,
they confabulate: typically, they respond to cues in their immediate environment
to construct a story. They might, for instance, take the doctor’s white coat to
be a baker’s apron, and, filling in some detail from their preserved memory of
earlier life, confabulate that they are visiting a friend who is a baker. Asked
what they did yesterday, they might recount an event that happened to them
forty years earlier. Confabulation is, apparently, not lying: confabulators
appear to sincerely believe the tales they concoct.

There
are a number of other strange neurological syndromes that centrally or
typically involve the assertion of falsehoods without intentional lying. They
include anosognosia (denial of illness, typically, the denial that one is
suffering from hemiplegia following a stroke), Anton’s syndrome (denial of
blindness), and delusions such as Capgras’s delusion (the delusion that people
to whom the patient is close have been replaced by impostors) and Cotard’s
delusion (the delusion that the patient is dead). Hirstein argues that all of
these syndromes should be understood as confabulatory syndromes, and given a
unified explanation. He also holds that a unified account of confabulation will
shed light on several other disorders, most notably sociopathy and
obsessive-compulsive disorder.

All
of the confabulatory syndromes, as Hirstein recognizes, appear to involve
brain-damage. Examining which areas of the brain are compromised therefore
seems to be a promising approach to explaining them. After an extended (and,
for a philosopher, somewhat tedious) excursion through neuroanatomy, Hirstein
advances a two-stage explanation of confabulation. He suggests that normal
brains have separate modules (my term, not his; no implications about
encapsulation are intended) for the generation of explanatory hypotheses and
for checking these hypotheses for consistency and plausibility. Confabulation
occurs when both modules are damaged. In that case, wild hypotheses are
produced by the generation module, and are allowed to pass (or go unexamined)
by the checking module. When the damage to one or the other module (or both; Hirstein
is far from clear on this point) is domain-specific, we get confabulation
restricted to a certain topic. We get, for instance, the patient who remains
globally rational, but denies that her left arm is paralyzed. When the damage
is more widespread, the confabulation spreads across more domains.

Hirstein
hopes that by understanding the ways in which the mind breaks down, we can get
a better understanding of its normal processes. Specifically, he hopes that
understanding confabulation will shed light on normal self-deception. He
advances some intriguing hypotheses about how self-deception, which he
understands in a relatively traditional way, could be possible. Self-deception,
understood in a traditional fashion (rather than in the deflationary way
proposed independently by Al Mele and Annette Barnes) is puzzling, because it
requires that otherwise rational agents are, not merely mistaken about some
proposition, but actively deceiving themselves about it. Do we not need to know
the truth about something in order to deceive ourselves about it? And if we
know the truth, then are we not undeceived? How is it possible for someone both
to believe something and not to believe it?

Hirstein
suggests that the same mechanisms that operate in confabulation may be at work
in self-deception. In confabulation, the checking mechanisms are damaged or
destroyed. In normal self-deception, they are functioning normally, but there
may be brain processes that direct the self-deceptive representation away from
the checking processes. He also suggests an intriguing way in which a
self-deceptive person might be able to, in some sense, simultaneously maintain
contradictory beliefs. Hirstein suggests that full-blown beliefs are
represented conceptually in the mind, but that there are inferior grades of
representation. For instance, information might be represented in what he calls
analog form, in which it is not conceptualized. A topographic map of space or
of one’s own body is one kind of analog representation. Though we may not be
able simultaneously to maintain conflicting (conceptual) beliefs, we can
maintain a conceptual belief which conflicts with one or more of our analog
representations.

How
do these two factors allegedly at work in self-deception interact? Is either
sufficient for self-deception, or are they jointly necessary? Hirstein does not
say. Unfortunately, this kind of lack of clarity about the mechanisms he
proposes is typical. Consider his explanation of his main target,
confabulation. Hirstein suggests that mind-reading deficits – an inability to
represent or to simulate the mental states of others’ – may be important in
confabulation. But how? When he advances his official two-stage theory,
mind-reading is dropped. And indeed, it is difficult to see how a mind-reading
deficit could be integrated into his theory. One possibility is that we might
utilize the responses of others as an additional check on our hypotheses; so
that the orbitofrontal cortexes of interlocutors could replace or supplement
our own. If this were the case, we might get short-lived confabulatory
syndromes, in patients whose orbitofrontal cortexes are damaged but who retain
sufficient mind-reading facility to compensate. Equally, however, it may be
that confabulators do pick up on the responses of others, but this only spurs
them to ever-changing stories; some case studies seem to provide evidence for
this hypothesis.

In
any case, the two-stage theory seems to have a stage too many. Hirstein
suggests that confabulation requires both the generation of implausible
hypotheses, and the failure of checking mechanisms. This is clearly
false for some confabulations, and may be false for all of them. Some
confabulations are, as he notes, quite plausible: if you did not know that the
confabulator had been hospitalized for the past six months, you would have no
difficulty accepting their stories. Why think, then, that the mechanism for
generating explanations needs to malfunction to produce such confabulations?
Indeed, it may be that even the wildest hypotheses are generated by normally
functioning mechanisms. It may that fantastic scenarios are routinely generated
by sub-personal mechanisms in the brain of normal persons. In that case, all
confabulations might simply be failures of checking mechanisms. Confabulations
might be verbal analogues of utilization behavior: we may regularly produce
such hypotheses, and would accept them but for the winnowing effects of our
checking mechanisms. Indeed, Hirstein himself seems to suggest as much at various
places in the book. When he advances his official explanation, however, the
suggestion is dropped.

Should
we substitute a one-stage explanation of confabulation for the two-stage
mechanism Hirstein proposes? Not, I suggest, if our task is to explain the
range of phenomena that Hirstein calls confabulation. These phenomena seem to
be too disparate to be given a unified explanation. It may be that neither
the generation nor the checking mechanisms are damaged in some
confabulators. Some confabulation may be ‘gap-filling’, of an entirely normal
kind. Perhaps we routinely explain our actions, to ourselves and to others, by
reference to environmental cues (this would be a type of extended mind
hypothesis, of the kind associated with Andy Clark, among others). Perhaps I
normally rely upon such information to trigger relevant autobiographical
memories. The Korsakoff’s suffer, or the participant in a split-brain
experiment, may be engaged in entirely normal kinds of explanation-giving. The
only difference between them and us is that they are cut off from crucial
sources of information, which renders their explanations highly unreliable.

There
is another reason to doubt that a unified explanation can be given of the
entire range of (what Hirstein calls) confabulation syndromes. Some
confabulations are much stranger than others, and much harder to explain. For
instance, it is far from clear that Capgras sufferers wholeheartedly believe
their delusions, as Hirstein contends (he consistently overestimates the extent
to which their behavior is consistent with the content of their delusions).
Moreover, some (supposedly) confabulatory syndromes leave the person
more or less intact, accentuating the oddness of their claims. Sufferers from Korsakoff’s
syndrome appear no longer to have the resources to detect the inconsistencies
and the implausibilities in their claims, since they cannot remember them for
long enough. But some sufferers from anosognosia are globally rational and
generally unimpaired. How does the malfunction of a domain-specific checking
mechanism result in claims as wild as the claim, on the part of a blind person,
that their eyesight is fine? Such a claim has entailments which spread across
many domains, and a globally rational person ought to be able to detect the
inconsistencies between their claims and their behavior. We have little
evidence that our checking processes are as discrete as Hirstein’s hypothesis
requires.

It
may be that some confabulations are explained by entirely normal inferential
procedures, whereby we all attempt to construct the narratives of our lives for
ourselves and for others, and that others are not explained by any mechanism Hirstein
canvases. Some confabulations — Korsakoff’s, and perhaps some of the delusions
— may be the product of relatively normal attempts to explain abnormal
experiences, whereas others seem to be produced by abnormal mechanisms, which
have yet to be fully comprehended.

Rather
than see Hirstein’s book as advancing a credible theory of confabulation, I prefer
to see it as a collection of stimulating, sometimes mutually exclusive,
hypotheses and speculations, some of which may constitute partial explanations
for some of the syndromes he examines. There is a great deal of stimulating
material in Brain Fiction, and a number of ideas and speculations worth
exploring, both in the laboratory and using the tools of philosophy. For all
its many virtues, however, it does not present us with a satisfactory theory
explaining the entire range of confabulatory syndromes, or even give us much
reason to think that there is such a theory to be had.

© 2005 Neil Levy

Dr Neil Levy is a fellow of
the Centre for Applied
Philosophy and Public Ethics at Charles Sturt
University, Australia. He is the author of two monographs
and over a dozen articles and book chapters on Continental philosophy, ethics
and political philosophy. He is currently writing a book on moral relativism.

Categories: Philosophical, Psychology