Sensory preconditioned and second-order conditioned responding are each well-
documented. The former occurs in subjects (typically rats) exposed to pairings of two …

Higher-order conditioning results from a simple training procedure: Pairing two relatively
neutral conditioned stimuli, A and X, allows properties separately conditioned to X (eg …

Learning to associate cues, both directly and indirectly, with biologically significant events is
essential for survival. Second-order conditioning (SOC) involves forming an association …

Avoiding stimuli that were previously associated with threat is essential for adaptive
functioning, but excessive avoidance that persists in the absence of threat can turn …

How does a stimulus never associated with danger become frightening? The present study
addressed this question using a sensory preconditioning task with rats. In this task, rats …

Simple Summary Threat conditioning is a process by which animals learn about danger. As
such, this process has been extensively studied as a model of how humans develop fears …

The basolateral amygdala complex (BLA) and infralimbic region of the prefrontal cortex (IL)
play distinct roles in the extinction of Pavlovian conditioned fear in laboratory rodents. In the …

Associative learning is often considered to require the physical presence of stimuli in the
environment in order for them to be linked. This, however, is not a necessary condition for …

It is widely accepted that activation of NMDA receptors (NMDAR) is necessary for the
formation of fear memories in the basolateral amygdala complex (BLA). This acceptance is …

The opioid receptor antagonist naloxone enhances Pavlovian fear conditioning when rats
are exposed to pairings of an initially neutral stimulus, such as a tone, and a painful foot …