The functional approach of biological research in psychiatry.

When neurobiological investigation looks beyond nosological perspectives into the search for correlations between isolated symptoms or specific behaviour patterns (some of which may be normal) and laboratory findings, many controversies seem to become clear. A paradigm of this approach is the Serotonin (5-HT) involvement in a wide range of psychiatric disorders and specific behaviour patterns all of them characterized by a poor control of impulses. Psychopharmacotherapy with substances able to interfere with the metabolism of this neurotransmitter, mostly antidepressants, are able to compensate what appear to be very dissimilar conditions. Therefore, the hypothesis that Serotonin is important for the control of impulses is a key to the interpretation of many findings and to the penetration of the complex field of biological substrate of psycho (patho) logy.