Development of Limbic System Stress-Threat Circuitry

Abstract

How an animal responds to environmental stressors and threats is essential for survival. These responses are governed through an interconnected circuit in the brain dubbed the limbic system. Three main structures of the limbic system are the amygdala, bed nucleus of the stria terminalis (BNST), and hypothalamus. Together these structures define a central stress-threat circuit. This chapter describes the most up to date knowledge of how these structures function in regulating responses to stressors and how each of these structures is formed from embryonic development. This knowledge of the underlying biology of these regions is essential to design rational therapeutic approaches for conditions, such as post-traumatic stress disorder (PTSD) that are characterized by dysregulation of the stress-threat system. In this chapter, we also describe the critical unanswered questions in the field of stress-threat research and potential future research directions.