Context plays a central role in retrieving (fear) memories. Accordingly, context manipulations are inherent to most return of fear (ROF) paradigms (in particular renewal), involving contextual changes after fear extinction. Context changes are, however, also often embedded during earlier stages of ROF experiments such as context changes between fear acquisition and extinction (e.g., in ABC and ...

Systemic fibroblast growth factor 2 (FGF2) has been shown to enhance extinction of conditioned fear and attenuate subsequent relapse in developing rats. However, it is not clear whether FGF2 has the same effect in adult rats, and furthermore, the neuroanatomical locus of the effect of FGF2 on extinction is unknown. These experiments examined the effect of 200 ng of FGF2, infused bilaterally int...

Accumulating evidence indicates the key role of alpha-calcium/calmodulin-dependent protein kinase II (alphaCaMKII) in synaptic plasticity and learning, but it remains unclear how this kinase participates in the processing of memory extinction. Here, we investigated the mechanism by which alphaCaMKII may mediate extinction by using heterozygous knock-in mice with a targeted T286A mutation that p...

We investigate the spatial distribution of the intrinsic extinction in the starburst dwarf galaxy NGC 1569 using an extinction map of the whole galaxy derived from the Hα/Hβ emission line ratio. We differentiate the extinction in the H ii regions from the extinction of the diffuse gas. The intrinsic extinction shows considerable variations over the plane of the galaxy, from negligible extinctio...

We have previously shown that fear extinction is accompanied by an increase of synaptic efficacy in inputs from the ventral hippocampus (vHPC) and mediodorsal thalamus (MD) to the medial prefrontal cortex (mPFC) and that disrupting these changes to mPFC synaptic transmission compromises extinction processes. The aim of this study was to examine whether these extinction-related changes undergo f...

Behavioral extinction is an active form of new learning involving the prediction of nonreward where reward has previously been present. The expression of extinction learning can be disrupted by the presentation of reward itself or reward-predictive stimuli (reinstatement) as well as the passage of time (spontaneous recovery) or contextual changes (renewal). The following experiments replicated ...

Cue exposure treatment (CET) attempts to reduce the influence of conditioned substance cues on addictive behavior via extinction, but has received only modest empirical support in clinical trials. This may be because extinction learning appears to be context dependent and a change in context may result in a return of conditioned responding (i.e., renewal), although this has received only limite...

Extinction bursts are characterized by a temporary increase in responding when drug access is withheld from rats trained to self-administer drugs of abuse. Thus far, one study has examined extinction bursts for nicotine self-administration using a 23-h access paradigm [1]. Here we examined extinction bursts using previously published and unpublished data in which rats were trained to self-admin...

Recent work has led to a better understanding of the neural mechanisms underlying the extinction of Pavlovian fear conditioning. Long-term synaptic changes in the medial prefrontal cortex (mPFC) are critical for extinction learning, but very little is currently known about how the mPFC and other brain areas interact during extinction. The current study examined the effect of drugs that impair t...