How stress and glucocorticoids timing-dependently affect extinction and relapse

Area of Science:

• Neuroscience
• Psychology
• Pharmacology

Background:

• Extinction learning is crucial for exposure therapy effectiveness.
• Glucocorticoids (GCs), like cortisol, are investigated for augmenting extinction learning.
• Relapse remains a significant challenge in treating psychological disorders.

Purpose of the Study:

• To introduce the STaR (Stress Timing affects Relapse) model.
• To elucidate the timing-dependent effects of stress and GCs on extinction and relapse.
• To provide a framework for understanding and preventing relapse.

Main Methods:

• Review of existing research on stress, GCs, and extinction learning.
• Theoretical modeling (STaR model) to explain timing-dependent effects.
• Analysis of neural mechanisms involving the amygdala, hippocampus, and prefrontal cortex.

Main Results:

• Pre-extinction stress/GCs enhance context-independent memory consolidation, reducing relapse risk after context change.
• Post-extinction stress/GCs improve context-bound extinction consolidation.
• Pre-retrieval stress/GCs impair extinction retrieval and increase relapse, potentially via amygdala or prefrontal cortex disruption.

Conclusions:

• The timing of stress/GC administration critically influences extinction memory and relapse.
• The STaR model offers insights into cortisol's effects on emotional memory contextualization.
• Understanding these mechanisms can optimize therapeutic interventions to prevent relapse.