CRH and Anxiety: In further support of these distinct functional roles, studies in rodents show that lesioning the amygdala eliminates conditioned fear to auditory (13) and visual conditioned stimuli (14) and reduces fear-potentiated startle (15), but does not alter anxiety-like behavior in an elevated plus maze (15) or anxiety-like responses to bright light or corticotropin-releasing hormone (CRH) injection (14).