Modulating amygdala responses to emotion: evidence from pharmacological fMRI

The use of functional MRI (fMRI) in combination with pharmacological challenges has increased exponentially in recent years, motivated by the idea not only to elucidate the neurochemical foundations of human emotional and cognitive faculties, but also to optimize human brain function in healthy individuals and identify novel drug targets, with the ultimate goal to design more specific pharmacological therapies for the various disorders of human emotion and cognition. In particular, emotional responding of the amygdala has become a central interest, and pharmacological fMRI has been used to specifically probe, and modulate, amygdala activation in response to facial expressions of emotion and emotionally laden scenes. This article reviews recent fMRI experiments manipulating the amygdala's physiological response to such stimuli by pharmacological means and lays a particular focus on monoaminergic, glutamatergic, GABAergic, and hormonal/peptidergic challenges.