There are sex differences in anxiety disorders with regard to occurrence and severity of episodes such that females tend to experience more frequent and more severe episodes. Contextual fear learning and generalization are especially relevant to anxiety disorders, which are often defined by expressing fear and/or anxiety in safe contexts. In…

In signaled active avoidance (SigAA), rats learn to suppress Pavlovian freezing and emit actions to remove threats and prevent footshocks. SigAA is critical for understanding aversively motivated instrumental behavior and anxiety-related active coping. However, with standard protocols ~25% of rats exhibit high freezing and poor avoidance. This has…

Multiple lines of evidence suggest that glucocorticoid hormones enhance memory consolidation of fearful events. However, most of these studies involve male individuals. Since anxiety, fear, and fear-associated disorders present differently in male and female subjects we investigated in mice whether male and female mice perform differently in a…

L-type voltage-gated calcium channels (LVGCCs) have been implicated in both the formation and the reduction of fear through Pavlovian fear conditioning and extinction. Despite the implication of LVGCCs in fear learning and extinction, studies of the individual LVGCC subtypes, Ca[subscript V]1.2 and Ca[subscript V] 1.3, using transgenic mice have…

Conditioned taste aversion (CTA) is an intensively studied single-trial learning paradigm whereby animals are trained to avoid a taste that has been paired with malaise. Many factors influence the strength of aversion learning; prominently studied among these is taste novelty--the fact that preexposure to the taste conditioned stimulus (CS)…

The absence of a2* nicotinic acetylcholine receptors (nAChRs) in oriens lacunosum moleculare (OLM) GABAergic interneurons ablate the facilitation of nicotine-induced hippocampal CA1 long-term potentiation and impair memory. The current study delineated whether genetic mutations of a2* nAChRs ("Chrna2"[superscript L9'S/L9'S] and…

Emotional states influence how stimuli are interpreted. High anxiety states in humans lead to more negative, threatening interpretations of novel information, typically accompanied by activation of the amygdala. We developed a handling protocol that induces long-lasting high and low anxiety-like states in rats to explore the role of state anxiety…

Generalization of fear can involve abnormal responding to cues that signal safety and is common in people diagnosed with post-traumatic stress disorder. Differential auditory fear conditioning can be used as a tool to measure changes in fear discrimination and generalization. Most prior work in this area has focused on elevated amygdala activity…

Surviving threats in the environment requires brain circuits for detecting (or anticipating) danger and for coordinating appropriate defensive responses (e.g., increased cardiac output, stress hormone release, and freezing behavior). The bed nucleus of the stria terminalis (BNST) is a critical interface between the "affective…

Calcitonin gene-related peptide (CGRP) infusions into the bed nucleus of the stria terminalis (BNST) evoke increases in startle amplitude and increases in anxiety-like behavior in the plus maze. Conversely, intra-BNST infusions of the CGRP antagonist CGRP[subscript 8-37] block unconditioned startle increases produced by fox odor. Here we evaluate…

Methylphenidate (MPH), introduced more than 60 years ago, accounts for two-thirds of current prescriptions for attention deficit hyperactivity disorder (ADHD). Although many studies have modeled MPH's effect on executive function, almost none have directly modeled its effect on long-term memory (LTM), even though improvement in LTM is a…

Four articles examining methodological applications of exposure therapy and its limited dissemination were briefly reviewed. Methodological articles included those by Abramowitz et al., Gryczkowski et al., and Weiner and McKay, which addressed couple treatment of obsessive-compulsive disorder (OCD), modification of evidence-based anxiety…

Beyond its trophic function, the neurotrophin BDNF (brain-derived neurotrophic factor) is well known to crucially mediate synaptic plasticity and memory formation. Whereas recent studies suggested that acute BDNF/TrkB signaling regulates amygdala-dependent fear learning, no impairments of cued fear learning were reported in heterozygous BDNF…

We tested the hypothesis that conceptual similarity promotes generalization of conditioned fear. Using a sensory preconditioning procedure, three groups of subjects learned an association between two cues that were conceptually similar, unrelated, or mismatched. Next, one of the cues was paired with a shock. The other cue was then reintroduced to…

People seem to differ in their conditionability, that is, the ease by which fear associations (neutral stimulus-unconditioned stimulus [CS-US] contingencies) are learned. Recently, the level of trait worry has been proposed as a predictor of heightened conditionability. The current research aimed to (a) further investigate this influence of…