Figure 1 -. Schematic representation of brain regions involved in anxiety and fear.

A threat stimulus is represented by the spider. The brain circuit involved in fear and anxiety is represented by the hippocampus, the amygdala, the stria terminalis and the frontal cortex. These regions are involved in both fear response after the immediate presence of the threat and in the anxious response of an individual facing uncertainty. BNST = Bed Nucleus of the Stria Terminalis.