A neuroendocrine mechanism for sustaining fear

Trends Neurosci. 2005 Dec;28(12):629-35. doi: 10.1016/j.tins.2005.09.009. Epub 2005 Oct 7.

Abstract

Fear is an adaptive response to recognition of a potentially dangerous event. Glucocorticoids are essential for maintaining a wide variety of behavioral events by their regulation of numerous genes; one such gene encodes corticotrophin-releasing hormone (CRH). CRH is involved in diverse behavioral responses to changing environmental demands. In this review, we focus on one aspect of glucocorticoid regulation of CRH--namely, fear-related responses to diverse classes of adverse events, such as those represented by contextual and cue-specific stimuli. Three extra-hypothalamic forebrain sites appear crucial for fear-related behavioral responses: the amygdala and the bed nucleus of the stria terminalis for sustaining adaptive fear-related behaviors, and the medial prefrontal cortex for modulating fear-related behaviors. Central regulation of CRH by glucocorticoids is important for adaptive and sustained fear-related behaviors, and its aberration is associated with anxiety and depressive disorders.

Publication types

  • Review

MeSH terms

  • Animals
  • Brain / physiology*
  • Corticotropin-Releasing Hormone / metabolism*
  • Fear / physiology*
  • Humans
  • Models, Neurological*
  • Neurosecretion / physiology
  • Neurosecretory Systems / physiology*

Substances

  • Corticotropin-Releasing Hormone