Positron Emission Tomography of the Human Brain in Relation to Psychological Defense Mechanisms in Patients with Multiple Sclerosis

Neurophysiological correlates of psychological defense mechanisms (PDMs) were studied in patients with multiple sclerosis. PDM scores (the Lifestyle Index test) were compared with the relative glucose metabolic rate (GMR) estimated by positron emission tomography. The results testified that the combined metabolic activity of the limbic system and the frontal and temporal brain areas of the right hemisphere plays a predominant role in the functioning of the PDM system. An increase or decrease in PDM activity was associated with changes in GMR in several brain structures of the parietal and frontal regions.