CBT works like Prozac
In a study by Dr. Lewis Baxter at the U.C.L.A. School of Medicine, patients with OCD who responded to either a reuptake inhibitor like Prozac or cognitive behavior therapy over 10 weeks showed virtually the same changes in their brains, decreases in the activities of the caudate nuclei and, thus, changes toward normal function.
When patients improved, the changes in their brains, as shown in the PET scans, looked the same regardless of whether they had received antidepressants or psychotherapy.
The intriguing finding from the PET scans is not limited to OCD. Two studies of patients with depression, reported last year in The Archives of General Psychiatry, compared the effects of interpersonal psychotherapy with an antidepressant on brain function, as observed in PET scans. In those studies, the depressed patients received interpersonal therapy, a short-term talk treatment that focuses on the effects of social relationships and major life events on mood.
In one study, a 12-week trial that compared an SSRI, Paxil, to interpersonal psychotherapy, Dr. Arthur Brody, also at U.C.L.A., found that depressed patients who responded to either treatment had nearly identical changes in their brain function, a decrease in the abnormally high activity seen in the prefrontal cortex before treatment.
In the second study, Dr. Stephen D. Martin at the research unit of Cherry Knowle Hospital in Sunderland, England, reported that six weeks of Effexor, an antidepressant that enhances both serotonin and norepinephrine, and interpersonal therapy produced similar effects in those depressed subjects who responded either to medicine or to psychotherapy. Each had shown an increase in the activity of the basal ganglia, a subcortical brain structure.
Although the observed changes with psychotherapy and antidepressant were similar in that study, they were not identical. Subjects with interpersonal therapy but not Effexor also had activation of a brain area called the cingulate gyrus, which responds to serotonin in the brain and has a role in regulating mood.
The studies show that pharmacotherapy and psychotherapy can produce remarkably similar effects on functional brain activity. But does that mean that antidepressants and psychotherapy are really equivalent?
In a word, no. Psychotherapy alone has so far been largely ineffective for diseases like schizophrenia, where there is strong evidence of structural, as well as functional, brain abnormalities. So it seems that if the brain is severely disordered, then talk therapy cannot alter it.
But it is clear that talk therapy can alter brain function. The reason may come from the elegant work of a Nobel Prize-winning psychiatrist and neurobiologist, Dr. Eric Kandel. Studying the simple and well-mapped nervous system of a sea slug, Aplysia, Dr. Kandel showed that learning leads to the production of new proteins and, in turn, to the remodeling of neurons.
Quoted from Source: http://www.ocdhope.com/how-cbt-works.php