Is It Psychological Or Biological

About 15 years ago, I was giving a lecture on psychiatric medication to
a group of MSW
students.  One student asked a question that was intended to
be
provocative.  She asked, "how can you justify giving
medication to
treat a problem that is obviously psychological in origin, like
posttraumatic stress disorder?"



What she was referring to, was a paradigm that was commonly held at the
time.  Specifically, there was this notion that some problems
were
psychological, and others were biological, in origin.  It was
thought, by some, that there was a clear distinction between the two
kinds of problems.  



A corollary to that was the notion that psychotherapy was the correct
treatment for psychological problems, and some kind of biological
treatment -- medication, for example -- was the correct treatment for
biological problems.



As an aside, I personally don't use the word "justification" to
describe anything in the practice of medicine.  

Rather, I think in
terms of "rationale."  There is only one possible rationale
for
the routine use of any medical intervention; it has nothing to do with
speculations about the origin of the problem being treated.
 The
rationale is that the treatment has been tested, and has been found to
work.



Anyway, back to the main point.  About one year ago, I was
leading
a seminar with some Ph.D. students in clinical psychology.  In
the
course of discussing something else, I mentioned, for historical
context, the idea that people had thought at one point that there was a
clear distinction between biological and psychological problems.
 A student chimed in: "But nobody really believes that any
more,
do they?"



Hmmm.  I am sure some people do.  What is more, it is
a paradigm that might be useful for them.  As href="http://signalplusnoise.com/">they href="http://www.utexas.edu/courses/bio301d/Topics/False.models/Text.html">say,
"all models are false; some are useful."  Personally, I have
found it to be useful only in a very limited sense.  



Sigmund Freud was said to have been an amateur archaeologists, and some
have thought that his hobby was related to the development of one of
his central theories.  He thought that the best way to solve
problems was to uncover their origins.  I think that does
work,
sometimes.  Often it does not.  Often, there are
simpler,
less time-consuming methods of approaching the problem, even within the
realm of psychotherapy.  Although the origin of a problem
might
suggest a particular solution, it certainly does not tell you a
priori what potential solution is most likely to work.
 



A good example of the lack of a clear distinction between psychological
and biological processes is found in a recent presentation on the
effects of childbirth.  Childbirth is obviously a biological
process for women.  The psychological and anatomical changes
are
rather obvious.  It is much less obvious, however, that there
are
biological changes that accompany fatherhood.  Therefore, it
might
be tempting to think of fatherhood as a time of psychological
transition, rather that a time of biological change.  



However, this is not something that one can discern merely by thinking
about it.  You have to do the study to learn the truth of the
matter.  And when you study the neurophysiology of new
fathers,
you do find that there are changes.



Is it really surprising that a person's physiology changes in response
to one's social environment?  



If the physiology changes, would it then be reasonable to think that
anatomy might change as well?



Fifteen years ago, it was thought commonly that the structure of the
brain did not change, once adulthood was attained, except for
degenerative changes caused by disease, or aging.  This is now
understood to be a misconception.



The study I referred to previously is described href="http://www.newscientist.com/article.ns?id=mg19125615.400&feedId=online-news_rss20">here.
 (HT: href="http://novaspivack.typepad.com/nova_spivacks_weblog/2006/07/fatherhood_boos.html">Minding
the Planet)

Fatherhood boosts male brains

25 July 2006

New Scientist



FATHERHOOD could be good for your brain, at least if you're a monkey.



It's already known that male primates, including men, experience
dramatic hormone changes when they become fathers. Yevgenia
Kozorovitskiy and her colleagues from Princeton University realised
that certain parts of the brain contain receptors for these hormones.
So they studied the brain structure of common marmosets (Callithrix
jacchus) that had become fathers. The species is rare among
mammals in
that fathers share in caring for their offspring.



In both first-time and experienced fathers with dependent offspring,
the team found structural changes in the prefrontal cortex, a region of
the brain important for planning and memory. In these areas the neurons
showed signs of enhancement, with a greater number of connections. They
also had more receptor sites for the hormone vasopressin...

href="http://en.wikipedia.org/wiki/Vasopressin">Vasopressin
is an interesting compound; it serves multiple functions in the body,
and it is not obvious why that one compound does so many different
things.  It is one factor that controls the salt-water
balance; it
contributes to regulation of blood sugar levels; it affects clotting;
and it has various effects in the brain.  (See href="http://scienceblogs.com/clock/2006/07/circadian_quackery.php">Bora,
Carl,
and href="http://scienceblogs.com/pharyngula/2006/07/a_simple_story_gets_complicate.php">PZ
for details on the role of vasopressin in circadian rhythms and in pair
bonding.)



I could get into a discussion of the supposed behavioral effects of
vasopressin, but my sense of the state of knowledge, at this point, is
that scientists do not really understand it well enough to say anything
with much authority.



As Carl and PZ pointed out, these things are never simple.
 Attempts to relate one neurotransmitter
with one behavior usually turn out to be fallacious. Even so, it is
clear that there is a biological basis to behavior.



Does that mean that behavior is biologically-driven, and that
psychology has nothing to do with it?  Of course not. It would
be more
accurate to say that biology and psychology are two different models;
each model can be used to explain behavior; and in some cases, one
model is more useful than the other.