Threat Reversal Abnormality in Patients With Anxiety Disorders

The goal of this clinical trial is to explore the flexibility of threat control and underlying neural mechanism based on the threat reversal paradigm (a highly validated new paradigm where threat learning and inhibition are required) in patients with anxiety disorders (mainly generalized anxiety disorder). The hypotheses are: 1. Threat reversal abilities are hypothesized to be impaired in patients with anxiety disorders compared to healthy normal subjects, which are assumed to be associated with anxiety symptoms. 2. The neural mechanism underlying threat reversal abnormalities in patients with anxiety disorders is hypothesized to involve the prefrontal cortex, amygdala, and hippocampus. 3. The repetitive stimulation to the core brain regions of threat reversal is assumed to improve threat reversal abilities and anxiety symptoms of patients.