 "I
just take each day as it comes," says Virginia Hasselbach,
a housewife in her 40s. "I used to think that my
meds kept my depression in check. But now I'm afraid I'm
going to wake up one day and kill myself," she admits.
Controversy over the safety of some psych drugs is still
raging on, spreading doubt and fear among patients. But
for disorders such as major depression, there's little
else that you can give patients to help them cope, right?
Not necessarily. Some specialists disagree with the one
therapy fits all approach. A growing body of evidence
now shows that talk therapy can be a potent modifier of
faulty brain chemistry. This nonprescription option has
even been shown to stack up to standard psychotropic drugs.
At a recent meeting of the American Association of Directors
of Psychiatric Residency Training in New Orleans, Dr Ari
Zaretsky, Head of the Cognitive Behaviour Therapy Clinic
at Sunnybrook and Women's College Health Sciences Centre
in Toronto, cited some of the many recent trials that
support this new understanding of the benefits of psychotherapy.
"We now have evidence-based studies showing that
both cognitive behavioural therapy (CBT) and interpersonal
psychotherapy produce observable biological brain effects.
Of course, this shouldn't be surprising, because it's
now well-known that whenever learning takes place, the
brain changes," said Dr Zaretsky. He also pointed
to several studies that demonstrate biological changes
that accompany CBT therapy. In one, thyroid hormone levels
-- known to decrease when patients respond to antidepressant
drugs -- dropped in 17 depressed patients who responded
favourably to 20 CBT sessions.
Seeing
is believing
Brain changes in response to CBT have also been revealed
via positron emission tomography (PET) scans. In one
study, patients with obsessive-compulsive disorder (OCD)
were randomized to two months of CBT or standard fluoxetine
treatment. Subjects in both groups had PET scans at
baseline and after treatment. Both sets of patients
had identical brain changes -- decreases in glucose
metabolism in the orbitofrontal cortex and right caudate.
"The orbitofrontal cortex appears to be involved
with impaired perceptions and interpretations of factors
in the environment. Behavioural therapy can reduce these
faulty error signals, which is reflected in the scans,"
explained Dr Zaretsky. In another study, 17 unmedicated
patients with major depression underwent 15 to 20 sessions
of CBT, and then had their brains PET scanned. These
scans were then compared to ones performed on 13 other
depressed patients who'd been treated successfully with
paroxetine alone. Good clinical response in each treatment
group was associated with brain changes. However, the
changes were specific to each treatment. The CBT patients
had increased metabolic activity in the hippocampus
and anterior cingulate and decreased metabolism in the
dorsal, ventral and medial frontal cortices. In contrast,
paroxetine-treated patients had greater metabolic activity
in the prefrontal cortex and decreases in the brainstem
and subgenual cingulate. Dr Zaretsky finds these results
particularly interesting, since the improved clinical
response in each group appeared to emerge from different
brain changes. "The CBT seems to work top-down,
whereas pharmacotherapy works more bottom-up,"
said Dr Zaretsky. He believes that CBT (16 to 20 sessions)
and interpersonal therapies are particularly helpful
in mild to moderate depression and in all anxiety disorders
-- including OCD, panic disorder, social anxiety disorder,
post-traumatic stress and others. At this time, there's
evidence that the improvements are sustained for at
least two years post-psychotherapy. As the data comes
in, more lasting effects are likely to be demonstrated.
Do long-term talk therapies induce observable brain
changes too? Evidence for techniques such as psychoanalysis,
which often continue for years, is harder to come by.
But according to Dr Arnold M Cooper, professor of Psychiatry
at Cornell University and former president of the American
Psychoanalytic Association, there's research that points
in that direction. Dr Cooper agrees that brain changes
accompany learning, by definition. He cites research
by Dr Eric Kandel, winner of the Nobel Prize in medicine
last year, to demonstrate that complex chemical and
structural brain changes accompany all forms of learning.
"Any effective psychotherapeutic technique that
results in real clinical improvement -- that is, changing
counterproductive habitual responses -- is bound to
be reflected by changes in the brain. We now have techniques
that allow us to observe these changes."
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