Sher L.
Med Hypotheses. 2001 Jul;57(1):101-2.

The author suggests that biological abnormalities related to the development of anxiety disorders can be classified as real or relative. Individuals with ‘real abnormalities’ are not able to function under any circumstances, including the circumstances that are natural for humans. Persons with ‘relative abnormalities’ can function under the natural circumstances, but are not able to function in situations that are unnatural for humans. Unnatural situations include being in elevators, flying airplanes, driving cars, etc. The author suggests that all humans can be classified into four groups:
1. Individuals with excellent ‘adaptational reserve’ never develop anxiety disorders;
2. Individuals with good adaptational reserve develop anxiety disorders only if they are subjected to extremely stressful, unusual situations (e.g. being a hostage);
3. Individuals with moderate adaptational reserve develop anxiety disorders if they are exposed to unnatural situations. They have ‘relative abnormalities’;
4. Individuals with poor adaptational reserve develop anxiety disorders in situations that are natural for humans. They have ‘real abnormalities’.