Can pcp and neuroscience jointly help schizophrenics?

Tony Downing (a.c.downing@newcastle.ac.uk)
Mon, 30 Nov 1998 13:04:07 +0000

I'm grateful for the cordiality with which distinguished list members have
dissented from my recent dissenting message about the search for a purely
contructivist definition of schizophrenia. But I was dissenting, and
espousing a medical model, partly because I felt it wrong to define these
sufferers merely as people who interpret their world in ways that are
enigmatic and troublesome to (some) others. I wanted to advocate that pcp
should be prepared to work in tandem with neuropsychiatry, rather than
insist on being a radical alternative.

The constructivist definitions offered so far as replacements of
"schizophrenic" have been over-inclusive in that, as Jim Mancuso himself
implied (with his mention of strife in Jakarta), they would include
revolutionaries and all kinds of dissidents - and also many criminals. Is
that really desirable?
The rhetoric of antipsychiatry recalls memories of the abuse of the medical
model to stifle dissidents in the USSR and elsewhere, but that treachery
does not prove that the diagnosis of schizophrenia is normally an act of
repression, or that it is avoidable in democracies. A definition that
ignored all psychobiological findings and made vexenigmatic construing
sufficient grounds for detention in a psychiatric ward could play even more
readily into the hands of unscrupulous administrators.

My main question asks why pcp has to be a game played with rules that say
you are out if you mention the brain. There is such a thing as brain
damage, and whether it is localised or subtly diffuse, anatomical or
chemical, it usually has cognitive consequences. Pcp is a science of
cognitions and it must be possible to apply pcp even to construals made by
people with damaged brains. If it is made axiomatic that nothing from
outside pcp can feed into a pcp explanation, there is a risk of pcp failing
to to bring, to the understanding of psychosis, concepts and explanations
that only pcp can provide.

I believe that that now, almost 20 years since the Mancuso and Sarbin book
was written, so much has happened in general neuropsychology, in functional
brain imaging, and in specific neuroscience findings about schizophrenia,
that it is no longer tenable to expect that purely social-cognitive
explanations will suffice. I admit, however, that "Schizophrenia", with or
without inverted commas, is a complex story, not yet brought to an entirely
clear resolution. May I, therefore, explain my main point with a simpler
and less contentious example: Capgras syndrome, the belief that somebody
emotionally close to the patient has been replaced by an almost identical
copy, who, nevertheless, is not really that person.

As expounded, e.g., by A.W. Young et al. (1993), British J. Pychiatry, 162,
695-8, Capgras syndrome arises because there are separate brain mechanisms
for:

a) recognising persons from their features of face, voice, etc., and
b) linking this to relevant social information.

It seems that some people sustain damage to the brain, from a variety of
possible causes, (e.g., traumatic injury, tumours, possibly involvement
with an epileptic focus, etc.) and that this damage destroys the mechanism
for b) while leaving a) operational.

How does the patient construe the results? Often, it seems, they come up
with constructions such as "This woman, who appears to be my wife, is
really a zombie who is impersonating her". - Or that she is some other
kind of imposter, e.g., a criminal who is holding the real wife prisoner
and has cunnngly had plastic surgery so as to look like her. The result
has sometimes been that the apparent imposter is killed by the patient.

In at least some of the cases of the Capgras phenomenon there is no doubt
that the phenomen is a direct sequal to and consequence of brain damage.
Yet, obviously, the subsequent construing by the sufferer falls within the
domain of pcp. Not everyone with the relevant brain damage comes to the
same psychotic conclusions. Stone & Young (1997), Mind & Language
12:.327-364 propose that, in Capgras cases,

"an additional reasoning bias...
leads [the patient] to put greater weight on forming beliefs that
are observationally adequate rather than beliefs that are a
conservative extension of their existing stock."

Medical models are not always a demeaning attack on the individual. People
with epilepsy have every reason to be grateful to the medical approach,
which has saved them from being thought mad or demonic and has provided
drugs that often control the problem. Capgras syndrome quite obviously
provides an example where part of the story has to lie within neurology
and cognitive science; a damaged set of brain mechanisms then feeds bizarre
and inadequate information into a construing system that still tries to
make sense of what it receives and interprets this in the light of the rest
of the sufferer's construct system. there is no need for PCP to stand
aloof from contributing to the overall understanding of such issues.

Schizophrenia is to some extent still an open question, but in the light of
the Capgras phenomenon it seems to me to be unwise and unnecessaryto set up
definitions that exclude the possibility of an interface with neuroscience.

Having said that, it may indeed be instructive to see how far we can go in
defining schizophrenia in purely constructivist terms, but there is no need
to be hostile towards psychiatry and the medical model, or to confuse
schizophrenics with revolutionaries or criminals.

==========================================================================
Tony Downing, M.A., Ph.D.
Lecturer, Dept. of Psychology,
University of Newcastle upon Tyne, NE1 7RU,
UK.

email: A.C.Downing@Newcastle.ac.uk
Phone +44 (0)191 222 6184 Mobile: +44 (0) 468 427 481
Fax: +44 (0)191 222 5622
==========================================================================

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%