A REVIEW OF FUNCTIONAL NEUROIMAGING IN MOOD DISORDERS - POSITRON EMISSION TOMOGRAPHY AND DEPRESSION

Objective: To examine the progress of positron emission tomography (PE T) as a tool for understanding the psychobiology of mood disorders, pa rticularly major depression and bipolar disorder. Method: Review of th e literature on functional imaging of mood disorders. Results: Functio nal imaging techniques have been used in psychiatric research as a non invasive method to study the behaviour and function of the brain. Tech niques used so far have involved the manipulation of emotion in health y volunteers, the evaluation of depressed (unipolar and bipolar as wel l as secondary depression), manic, and normal subjects under resting a nd various activation conditions, such as cognitive activation, acute pharmacological challenge, and chronic thymoleptic treatments. As a re sult, functional imaging studies tend to support abnormalities in spec ific frontal and limbic regions. Conclusion: Different PET methods dem onstrate consistent abnormalities in the prefrontal, cingulate, and am ygdala regions. These findings are in agreement with past animal and c linical anatomical correlates of mood and emotions.