Neural circuitry involving the amygdala (which regulates emotions like anxiety and fear, stimulating the HPA Axis and sympathetic nervous system) and hippocampus (which is implicated in emotional memory along with the amygdala) is thought to underlie anxiety.[55] People who have anxiety tend to show high activity in response to emotional stimuli in the amygdala.[56] Some writers believe that excessive anxiety can lead to an overpotentiation of the limbic system (which includes the amygdala and nucleus accumbens), giving increased future anxiety, but this does not appear to have been proven.[57][58]
Some people have only one or two attacks and are never bothered again. Panic attacks can occur with other psychiatric disorders. In panic disorders, however, the panic attacks return repeatedly and the person develops an intense fear of having another attack. Without help, this "fear of fear" can make people avoid certain situations and can interfere with their lives even when they are not having a panic attack. Therefore, it is very important to recognize the problem and get help.
There is a long list of signs and symptoms of an anxiety attack. But because each body is somewhat chemically unique, anxiety attacks can affect each person differently. Consequently, anxiety attack symptoms can vary from person to person in type or kind, number, intensity, duration, and frequency. If your symptoms don’t exactly match this list, that doesn’t mean you don’t have anxiety attacks. It simply means that your body is responding to them slightly differently.