Environmental certainty influences the neural systems regulating responses to threat and stress

Neurosci Biobehav Rev. 2021 Oct 18;131:1037-1055. doi: 10.1016/j.neubiorev.2021.10.014. Online ahead of print.

Abstract

Flexible calibration of threat responding in accordance with the environment is an adaptive process that allows an animal to avoid harm while also maintaining engagement of other goal-directed actions. This calibration process, referred to as threat response regulation, requires an animal to calculate the probability that a given encounter will result in a threat so they can respond accordingly. Here we review the neural correlates of two highly studied forms of threat response suppression: extinction and safety conditioning. We focus on how relative levels of certainty or uncertainty in the surrounding environment alter the acquisition and application of these processes. We also discuss evidence indicating altered threat response regulation following stress exposure, including enhanced fear conditioning, and disrupted extinction and safety conditioning. To conclude, we discuss research using an animal model of coping that examines the impact of stressor controllability on threat responding, highlighting the potential for previous experiences with control, or other forms of coping, to protect against the effects of future adversity.

Keywords: Controllability; Neural circuits; Predictability; Safety; Stress; Threat.

Publication types

  • Review