The Role of Norepinephrine in Emotional Processing

An understanding of the role of specific neurotransmitters in the neurocognitive functions mediating emotional processing is essential for the understanding and treatment of mood and anxiety disorders. One such disorder, currently regarded as untreatable, is psychopathy. Psychopathy has been linked with noradrenergic and amygdala disturbances. However, an understanding of the functional significance of the noradrenergic system in humans remains in its infancy. The goal of this protocol is to use targeted noradrenergic manipulations (yohimbine and guanfacine) in conjunction with specific neurocognitive and neuroimaging paradigms to consider the role of norepinephrine in reward and punishment processing. In particular, we wish to evaluate the hypothesis that increased norepinephrine levels following the administration of yohimbine will lead to enhanced formation and processing of stimulus-reward and stimulus-punishment associations, while decreased norepinephrine levels following the administration of guanfacine will reduce the formation and processing of stimulus-reward and stimulus-punishment associations. In addition, we aim to examine the hypothesis that increased norepinephrine levels will lead to increased neural response in the amygdala during either the formation, or processing, of stimulus-reinforcement associations.