Anxiety disorders, or "worry disorders", are conditions in which fear, worry, stress or other forms of abnormal and lasting anxiety are the main symptoms. These symptoms may be more or less troublesome, depending on their intensity and sensitivity to daily living conditions. In the most serious cases, the level of suffering and disability can be very high. These are nonpsychotic pathologies, which therefore do not alter the person's contact with reality: the sufferer is aware of their extreme fear and may thus question the behaviour when the anxiety level has decreased. The sufferer cannot fight against the anxiety and its consequences when he is confronted with it. The severity of anxiety disorders is also related to their potential complications, primarily depression and addictions, especially to alcohol or sedative drugs. The most common anxiety disorder is phobia, others being panic disorder, generalised anxiety, and post-traumatic stress disorder. In people with generalised anxiety (called GAD for Generalized Anxiety Disorders), any subject and pretext may be good as a source of worry and repetition. These may be serious things but also others that are much less serious, things that are possible, but very unlikely or without any real gravity. These worries, which intrude at any moment, ruin lives by preventing the patient from concentrating on the action in progress, and especially from enjoying the present moment, even when everything is going well. In addition to worries, generalised anxiety is manifested by permanent hypervigilance on the lookout for any sign of danger, with startle reactions at the slightest noise, and many signs of nervous tension, in the body and in behaviour: irritability, tension, headaches and various pains, digestive disorders, tremor, etc. Insomnia is also very frequent, because of this permanent tension, preventing a "disconnection" as night-time approaches. Generalized anxiety disorder is diagnosed when symptoms are present most of the time, for at least six months, and without an event that really justifies the worry: this can be called "stress-free stress". This disease affects many people, predominantly women. Symptoms may be present early in life in the form of an "anxious temperament", but they usually begin to become truly troublesome in the forties and become more and more invasive with age. Natural defences against worry become more difficult to employ over time, and there is often progressive exhaustion making it increasingly difficult to fight worries.