introduction: one of the hallmark symptoms of posttraumatic stress disorder (ptsd) is the impaired extinction of traumatic memory. single prolonged stress (sps) has been suggested as an animal model of ptsd, since sps rats exhibited the impaired fear extinction. oxytocin (oxt) has been recently suggested as a potential pharmacotherapy for treatment of ptsd. in this study, using sps rats we inve...

the purpose of the present study was to determine the role of medial prefrontal cortex (mpfc) dopaminergic system in fear conditioning response considering individual differences. animals were initially counterbalanced and classified based on open field test, and then were given a single infusion of the dopamine agonist, amphetamine (amph) and antagonist, clozapine (clz) into the medial prefron...

The formation of fear memory to a specific stimulus leads to subsequent fearful response to that stimulus. However, it is not apparent whether the formation of fear memory can affect other memories. We study whether specific fearful experience leading to fear memory affects different memories formation and extinction. We revealed that cued fear conditioning, but not unpaired or naïve training, ...

Numerous investigations have definitively shown amygdalar involvement in delay and contextual fear conditioning. However, much less is known about amygdala contributions to trace fear conditioning, and what little evidence exists is conflicting as noted in previous studies. This discrepancy may result from selective targeting of individual nuclei within the amygdala. The present experiments fur...

The role of the hippocampus in memory is commonly investigated by comparing fear conditioning paradigms that differ in their reliance on the hippocampus. For example, the dorsal (septal) portion of the hippocampus is involved in trace, but not delay fear conditioning, two Pavlovian paradigms in which only the relative timing of stimulus presentation is varied. However, a growing literature impl...

bstract—Fear conditioning and fear extinction play key oles in the development and treatment of anxiety-related isorders, yet there is little information concerning experienial variables that modulate these processes. Here we examned the impact of exposure to a stressor in a different envionment on subsequent fear conditioning and extinction, and hether the degree of behavioral control that the...

A key finding in studies of the neurobiology of learning memory is that the amygdala is critically involved in Pavlovian fear conditioning. This is well established in delay-cued and contextual fear conditioning; however, surprisingly little is known of the role of the amygdala in trace conditioning. Trace fear conditioning, in which the CS and US are separated in time by a trace interval, requ...

Early life trauma alters later life emotions, including fear. To better understand mediating mechanisms, we subjected pups to either predictable or unpredictable trauma, in the form of paired or unpaired odor-0.5 mA shock conditioning which, during a sensitive period, produces an odor preference and no learning respectively. Fear conditioning and its neural correlates were then assessed after t...

introduction: previous studies have demonstrated that the &beta-adrenergic; receptor antagonist propranolol impairs fear memory reconsolidation in experimental animals. there are experimental parameters such as the age and the strength of memory that can interact with pharmacological manipulations of memory reconsolidation. in this study, we investigated the ability of the age and the strength ...

OBJECTIVE Considerable research examines fear conditioning in adult anxiety disorders but few studies examine youths. Adult data suggest that anxiety disorders involve elevated fear but intact differential conditioning. We used a novel paradigm to assess fear conditioning in pediatric anxiety patients. METHOD Sixteen individuals with anxiety disorders and 38 healthy comparisons viewed two pho...