Table 1.

Glossary of key terms and definitions.

key term	definition
fear conditioning	experimental paradigm in which the pairing of an initially neutral stimulus (conditional stimulus; CS) to an aversive unconditional stimulus (US) leads to associative learning, such that subsequent presentations of the CS elicit a conditioned response (CR)
extinction	repeated presentations of the conditioned stimulus (CS) in the absence of an unconditioned stimulus (US) lead to a progressive decrease in conditioned responding
reinstatement	return of conditioned responding (return of fear) after exposure to an unsignalled stressor (e.g. a shock)
renewal	return of conditioned responding (return of fear) when the conditioned stimulus (CS) is presented in a context other than the extinction context
spontaneous recovery	return of conditioned responding (return of fear) after the passage of time following extinction