The Physiology of the HPA and Extended Amygdala in Mechanisms of Drug Use and Abuse

Abstract

BACKGROUND. This paper attempts to explain drug abuse, more specifically alcoholism, in terms of neurophysiology and psychological processes in order to gain a greater understanding of drug/alcohol addiction through stress systems and addiction mechanisms. METHOD. This was done by consulting online databases (PUBMED, EBSCO) and relevant textbooks for relevant information. RESULTS. It was found that the hypothalamic pituitary adrenal (HPA) axis and the extended amygdala were the major physiological systems associated with stress response and drug addiction. These systems work by promoting hedonic homeostatic dysfunction through psychological mechanisms such as a/b-processes, allostasis, sensitization and counteradaption. DISCUSSION. Other factors that increase the vulnerability of consuming drugs consist of genetic factors and external stress. Future research should focus on genetic factors because of the little knowledge and direct understanding we have of genetic factors contributing to the transition from alcohol use to alcohol abuse. Deeper understanding of genetic factors on drug addiction would provide more effective treatment for those suffering from alcohol dependence.