The ability to learn, remember, and respond to emotional events is a powerful survival strategy. However, dysregulated behavioral and physiological responses to these memories are maladaptive. To fully understand learned fear and the pathologies that arise during response malfunction we must reveal the environmental variables that influence learned fear responses. Light, a ubiquitous environmen...

Fear learning occurs in response to positive prediction error, when the expected outcome of a conditioning trial exceeds that predicted by the conditioned stimuli present. This role for error in Pavlovian association formation is best exemplified by the phenomenon of associative blocking, whereby prior fear conditioning of conditioned stimulus (CS) A is able to prevent learning to CSB when they...

In contrast to a general model of stress, a functional model suggests that emotions may regulate stress responses in specific adaptive ways. The current study examined whether anger and fear during a challenging stress task (Trier Social Stress Task) were differentially associated with cortisol and proinflammatory cytokine responses to an acute stressor. Baseline anger and fear were related to ...

Following shock, rats exhibit a potentiated startle response to a sudden, loud noise. It has been suggested that this shock sensitization of the startle response can be used as a model preparation for studying unlearned fear. After reviewing the theoretical and empirical bases for this claim, the results of several recent studies that show that the shock sensitization of startle effect is actua...

Patients suffering from Idiopathic Environmental Intolerances (IEI) report health symptoms, referable to multiple organ systems, which are triggered by harmless odors and therefore medically unexplainable. In line with previous research that predominantly points towards psychological explanations, the present study tests the hypothesis that IEI symptoms result from learning via classical condit...

Stress exposure, depending on its intensity and duration, affects cognition and learning in an adaptive or maladaptive manner. Studies addressing the effects of stress on cognitive processes have mainly focused on conditioned fear, since it is suggested that fear-motivated learning lies at the root of affective and anxiety disorders. Inhibition of fear-motivated response can be accomplished by ...

Fear plays a significant role in the lives of many people, from crippling fear that prevents people from performing everyday activities, to that which is intentionally experienced from video game or horror movies. The physiological responses to fear-inducing stimuli may vary between individuals, but some common reactions include increased heart rate, respiration rate and muscle tension, collect...

Upon recall, a memory can enter a labile state in which it requires new protein synthesis to restabilize. This two-phased reconsolidation process raises the prospect to directly target excessive fear memory as opposed to the formation of inhibitory memory following extinction training. In our previous studies, we convincingly demonstrated that 40 mg propranolol HCl administration before or afte...

Post-traumatic stress disorder (PTSD) patients display pervasive fear memories, expressed indiscriminately. Proposed mechanisms include enhanced fear learning and impaired extinction or extinction recall. Documented extinction recall deficits and failure to use safety signals could result from general failure to use contextual information, a hippocampus-dependent process. This can be probed by ...

Post-traumatic stress disorder (PTSD) patients display pervasive fear memories, expressed indiscriminately. Proposed mechanisms include enhanced fear learning and impaired extinction or extinction recall. Documented extinction recall deficits and failure to use safety signals could result from general failure to use contextual information, a hippocampus-dependent process. This can be probed by ...