ABSTRACT

This chapter reviews the structure and function of the limbic system and illustrates how it is interconnected with the stress-response. Studies of electrical stimulation elicited emotions, and emotions in turn activated the limbic system. Physiological studies of patients with post-traumatic stress disorder (PTSD) associated with trauma are presented to illustrate how they have different state responses to startle and recall of trauma, and how their basal levels of stress physiology are dysregulated from homeostasis. The pathophysiology of trauma may involve dysfunction of several brain structures, particularly the amygdala and the hippocampus in the limbic system. The chapter also focuses on limbic system symptoms as they are associated with trauma, PTSD, and limbic system abnormalities. Since most of the recent research on emotions and the limbic system has been with patients with trauma history and/or PTSD, the findings are specifically relevant to environmental illness patients with similar characteristics.