title: [Review of placebo effect and re-evaluation of psychotherapy focusing on depressive disorders].
abstract: It is well known that based on the findings of double-blind studies of antidepressants, placebos have an unexpected positive effect on depression. Neuroimaging studies comparing the effect of antidepressants and placebos by means of PET revealed that both placebo and fluoxetine treatment induced regional metabolic increases in such areas as the prefrontal and posterior cingulate, and metabolic decreases in such areas as the subgenual and thalamus. It is indicated that placebos have a similar pharmacological effect as antidepressants (Mayberg et al., 2002). This biological finding strongly suggests that when a patient takes an antidepressant administered by a doctor, and the treatment is effective, a placebo effect is always implicitly appended to any pharmacological effect of the medicine. In other words, the overall curative effect by administration of antidepressants can be schematically expressed as follows: Overall curative effect by antidepressant = Effect specific to pharmacotherapy + Placebo effect. In this case, the placebo effect is based on the patient's expectation and hope of recovery that is working consciously, preconsciously, and unconsciously; it is an essential condition that the patient has confidence and an expectation that the medicine will work. Such linguistic elements and subjective factors help to correct the metabolism of the cranial nerve system that was changed by depression, and thus encourages a cycle of resilience to restore the system to its former healthy state. This mechanism can be considered to operate as a top-down system. As easily inferred from the fact that the placebo effect is made up of a linguistic element and an emotional element found in the doctor-patient relationship, the formation of the doctor-patient relationship itself can be considered to be by tacit consent effective as a kind of psychotherapy. A brief look at the recent biological studies on the placebo effect lends support to the possibility that even one word spoken by a physician to a patient may bring about an effect that corrects any neurotic malfunction inside the brain. This paper indicates that non-pharmacotherapy such as psychotherapy or psychological and social support may have a similar effect to the administration of actual medicines that directly work on neurotransmitters in the brain.
authors.affiliation: Department of Psychiatry, Jichi Medical Universuty.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kato
mesh_terms: D000928:Antidepressive Agents / Q000627:therapeutic use; D003866:Depressive Disorder / Q000188:drug therapy*; D006801:Humans; D015990:Placebo Effect; D011613:Psychotherapy / Q000379:methods; D016896:Treatment Outcome
chemical_list: D000928:Antidepressive Agents