Researchers from different schools of thought have different opinions about the causes of anxiety disorders. These opinions are not necessarily conflicting, but rather complementary. First, somatic diseases or biological dysfunctions, although they would not be the only cause of anxiety disorders. However, in some rare cases, a patient’s anxiety symptoms can be triggered by somatic factors, for example, hyperthyroidism or adrenal tumors. Many researchers have tried to discover if it is the central nervous system, specifically certain neurotransmitters, that is responsible for triggering anxiety in patients with anxiety disorders. Much research has focused on two neurotransmitters: norepinephrine and serotonin. Many studies have found that when patients are in a state of anxiety, their brain levels of norepinephrine and serotonin change dramatically, but it has not been determined whether these changes are a cause or a consequence of anxiety symptoms. Second, cognitive processes, or thinking, play an extremely important role in the development of anxiety symptoms. Studies have found that depressed patients are more inclined than the general population to interpret ambiguous, even benign, events as harbingers of crisis, to think that bad things will fall into their laps, to believe that failure awaits them, and to underestimate their ability to control negative events. Third, anxiety disorders are more likely to occur in the presence of stressful events. I argue that since anxiety is an instinct of positive stress, stressful behaviors, including stress preparation, are the main cause of anxiety becoming a disorder. Due to the reinforcement of stressful behaviors, in some cases (e.g., lack of information), there is a wrong stimulus-response association, or the degree is not properly controlled, so that the accumulated or invoked psychological energy during stress preparation is not effectively released, and persistent tension, panic, etc., affects the subsequent behaviors, while the disturbance (overproduction) of thyroxine and norepinephrine, hormones related to tension, has an effect on the above The process has an amplifying effect. As for worry, paranoia is also a sign of excessive thinking energy.