The Corpus Callosum

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
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
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
the routine use of any medical intervention; it has nothing to do with
speculations about the origin of the problem being treated.
rationale is that the treatment has been tested, and has been found to

Anyway, back to the main point.  About one year ago, I was
a seminar with some Ph.D. students in clinical psychology.  In
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
do they?”

Hmmm.  I am sure some people do.  What is more, it is
a paradigm that might be useful for them.  As they 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
sometimes.  Often it does not.  Often, there are
less time-consuming methods of approaching the problem, even within the
realm of psychotherapy.  Although the origin of a problem
suggest a particular solution, it certainly does not tell you a
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
rather obvious.  It is much less obvious, however, that there
biological changes that accompany fatherhood.  Therefore, it
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
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 here.
 (HT: 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
) 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…

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 Bora,
and PZ
for details on the role of vasopressin in circadian rhythms and in pair

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.


  1. #1 Mark Frank
    August 6, 2006

    This reminds me of a question my mother once asked me. “Is a real coal fire really more cheerful or is it just psychological?”

  2. #2 BilZ0r
    August 6, 2006

    “how can you justify giving medication to treat a problem that is obviously psychological in origin, like posttraumatic stress disorder?”

    I sure hope that wasn’t an advanced class. You can justify it easily, the roll of a physician is to increase the quality of life of their patients, anything that does it, is good.

    Moreover, making a distinction between psychological and biological is ridiculous, what generates the psyche? The biological processes of the brain. A psychological problem is simple a reactive biological event. It’s like a surgeon saying they wont work on problems caused by anything but underlying genetic disorders, “a bullet wound is a reaction to the environment, it’s not a real syndrome”

  3. #3 Richard
    November 28, 2010

    “The current research indicates that biological and genetic risk factors (or predisposition) *are fundamental* to mental illnesses, but psychological factors are also *believed* to play a factor both in the incidence (whether a person develops a mental illness) and outcomes (how well they recover from a mental illness).”

    “Are fundamental” versus “believed”? This is inaccurate and misleading. They are both equally important. As you know, only 50 percent of identical twins both develop schizophrenia. If it is true that it is a genetic disorder, it is also true that it is a non-genetic disorder. Of course, neither of these statements are true.

  4. #4 supratall
    December 27, 2010

    I sure hope that wasn’t an advanced class. You can justify it easily, the roll of a physician is to increase the quality of life of their patients, anything that does it, is good.

  5. #5 dr.vahid razmgiri
    August 26, 2011

    hi,I am one of many other iranian psychiatrists that because of HEADS! wrongs can not take international viza cart .then i can only download free pdf !. please help me.

New comments have been temporarily disabled. Please check back soon.