The limbic system, involved with the emotions of rage, arousal and fear, is suspected to be the location for anticipatory anxiety. This area is rich with benzodiazepine receptors so benzodiazepine medications are most effective in the limbic area. Paths linking the brain stem with the limbic system can produce anticipatory anxiety following a panic attack and vice versa. The limbic system is also sensitive to changes in blood flow caused by hyperventilation. Abdominal breathing and relaxation decreases anticipatory anxiety by quieting the limbic system, blocking a potential trigger path for a panic attack.
Agoraphobia is a learned behavior pattern which is probably located in the frontal cortex.
Cognitive-behavioral treatments are most effective at this higher level of the brain. Discharges from the brain stem may be interpreted by the frontal cortex as a dangerous, life-threating event, and associations between the panic attack, environment, and thoughts are made. Decending paths from the frontal cortex enable catastrophic thoughts to stimulate the brain stem and cause panic attacks. Thus the three areas of the brain all intercommunicate during different phases of a panic episode. According to the model, different treatments for panic disorder and agoraphobia affect different aspects of the illness and different parts of the central nervous system.