BACKGROUND Enhanced acquisition and delayed extinction of fear conditioning are viewed as major determinants of anxiety disorders, which are often characterized by a dysfunctional hypothalamic-pituitary-adrenal (HPA) axis. METHOD In this study we employed cued fear conditioning in two independent samples of healthy subjects (sample 1: n=60, sample 2: n=52). Two graphical shapes served as cond...

T cerebellum has long been known as a center of fine motor control and sensory-motor integration. It also is appreciated as essential for the acquisition and expression of conditioned eye-blink responses, a type of discrete sensorymotor learning (1, 2). Recently, the cerebellum also has been implicated in acquiring (3–5) and expressing (6) ‘‘emotional’’ associative learning, which is commonly b...

Recent lines of research have focused on dissociating function between the dorsal and ventral hippocampus along space and anxiety dimensions. In the dorsal hippocampus, the CA1 subregion has been implicated in the acquisition of contextual fear as well as in the trace interval in trace fear conditioning. The present study was designed to test the relative contributions of dorsal (dCA1) and vent...

We have demonstrated previously that brain-derived neurotrophic factor (BDNF) signaling in the amygdala is required for the consolidation of fear memory. This study is designed to characterize the signal cascades by which fear conditioning modulates transcriptional and translational expression of BDNF. Real-time reverse transcription-coupled polymerase chain reaction showed a significant increa...

The two-factor theory postulates that classical conditioning proceeds through two stages, which support successive acquisition of emotional and motor responses. Emotional conditioning is thought to facilitate the subsequent acquisition of the motor response. This form of interaction between the two stages of learning can be investigated while considering the central role of the amygdala and the...

Fear conditioning is an important test in behavioral neuroscience to investigate the neural systems and molecular basis of various aspects of emotional learning across a wide range of species [1]. Dysfunction of the fear circuits is assumed to underlie mechanisms of affective disorders and is frequently investigated in rodent models. Traditional fear conditioning methods require frequent handli...

Fear memory is the best-studied form of memory. It was thoroughly investigated in the past 60 years mostly using two classical conditioning procedures (contextual fear conditioning and fear conditioning to a tone) and one instrumental procedure (one-trial inhibitory avoidance). Fear memory is formed in the hippocampus (contextual conditioning and inhibitory avoidance), in the basolateral amygda...

Lesion studies in animals have identified a critical role of the hippocampus in context fear conditioning. To extend these findings to human volunteers, we used functional magnetic resonance imaging to investigate neural responses associated with context fear conditioning in humans. Our novel conditioning paradigm consisted of aversive electrical shocks (unconditioned stimulus) that were delive...

The amygdala plays a critical role in fear conditioning, a model of emotional learning and cue-induced anxiety. In the lateral amygdala, fear conditioning is associated with an enduring increase in synaptic strength mediated through AMPA receptors and with a reduction in paired-pulse facilitation, reflecting an increased probability of neurotransmitter release. Here we show that NMDA-mediated t...

Social interactions with conspecifics markedly alter the neuroendocrine, behavioral and emotional responses to stressful events. Some of these effects involve observational learning and result in lasting changes of fear-motivated behavior. While most evidence reveals increased fearfulness after observation of fearful demonstrators (models) in a number of species, a few reports from human and no...