The emotional reactivity of rats with lesions of the dorsal portion of medial prefrontal cortex (mPFC) was examined using a classical fear conditioning paradigm. Conditioned fear behavior (freezing responses) was measured during both the acquisition and extinction phases of the task. Lesions enhanced fear reactivity to both the conditioned stimulus (CS) and contextual stimuli during both phases...

Fear generalization is an etiologically significant indicator of anxiety disorders, and understanding how to inhibit it is important in their treatment. Prior studies have found that reducing fear generalization using a generalization stimulus (GS) is ineffective in removing a conditioned fear that incorporates local features, and that topological properties appear to play a comparatively more ...

Several studies have shown that the isolated retrieval of a consolidated fear memory can induce a labile phase, during which extinction training can prevent the reinstatement, a form of relapse in which fear response to a fear-provoking context returns when a mild shock is presented. However, fear memory retrieval may also have another opposing result: the enhancement of fear memory. This impli...

Although impaired fear extinction has repeatedly been demonstrated in patients with anxiety disorders, little is known about whether these impairments persist after treatment. The current comparative exploratory study investigated fear extinction in 26 patients treated for their anxiety disorder in the years preceding the study as compared to 17 healthy control subjects. Fear-potentiated startl...

In humans, activation of the ventral striatum, a region associated with reward processing, is associated with the extinction of fear, a goal in the treatment of fear-related disorders. This evidence suggests that extinction of aversive memories engages reward-related circuits, but a causal relationship between activity in a reward circuit and fear extinction has not been demonstrated. Here, we ...

Agren, T., Engman, J., Frick, A., Bjorkstrand, J., Larsson, E. M., Furmark, T. et al. (2012). Disruption of reconsolidation erases a fear memory trace in the human amygdala. Science, 337, 1550-1552. Notes: Memories become labile when recalled. In humans and rodents alike, reactivated fear memories can be attenuated by disrupting reconsolidation with extinction training. Using functional brain i...

Background: Around 20% of birthing women report high levels of childbirth fear. Fear potentially impacts women’s emotional health, preparation for birth, and birth outcomes. Evidence suggests that personal and external factors contribute to childbirth fear, however results vary. Aim: To identify pyscho-social factors associated with childbirth fear and possible antenatal predictors of childbirt...

Fear conditioning studies in adults have found that posttraumatic stress disorder (PTSD) is associated with heightened fear responses and impaired discrimination. The objective of the current study was to examine the association between PTSD symptoms and fear conditioned responses in children from a highly traumatized urban population. Children between 8 and 13 years old participated in a fear ...