[Biologic base of anxiety disorders: recent progress].

We reviewed recent knowledge and a biologic base of anxiety disorders. As for brain image study, mainly study on PET, fMRI and NIRS has advanced. The neural circuit hypothesis of Gorman still attracts attention. We will think that characteristics of each anxiety disorder disease will become clear from these studies in future. We think that a genetic role will be associated with personality, character and gene study. We mention the connection between neuropeptides and anxiety in animal experiments. In addition, the past sensory stimulation in the amygdala, regarded as the center of anxiety, and the reinforcement of emotional ties is pointed out as an important thing for anxiety formation.