Chronic Illness and Trauma

This article describes research on the role of environmental factors affecting autonomic regulation and predisposition for states of sympathetic and parasympathetic dominance. Perspectives regarding the role of environmental factors in physiological regulation contribute to our increasing understanding of the impact of gene-environment interactions in the origins of chronic illness such as type 1 diabetes. This excerpt emphasizes research on the role of traumatic stress. II. TRAUMATIC STRESS Definition and physiology The definition of traumatic stress has been summarized as the experience of an event that is perceived by a relatively helpless individual to be both life threatening and inescapable [1, 2]. Although the delineation between different types of stress has been difficult to fully elucidate, useful factors in the characterization of traumatic stress are that it is associated with extreme fear and high emotional charge [1, 3, 4]. Highly emotional experiences promote the imprinting of an event [5], along with associated contextual environmental and physiologic cues, into procedural (unconscious) memory [1, 6]. In comparison with other types of conditioning, fear conditioning can occur following one trial and can be extremely long-lasting [1]. The imprinting of highly charged experiences creates conditioned responses that even when extinguished remain stored in memory and available for activation following exposure to an environmental trigger [5]. These characteristics of the nervous system represent innate survival strategies that serve as internal references to promote survival by enabling the organism to respond to future experiences with enhanced rapidity and efficiency [7]. rigins of Chronic Illness: