Today, psychological guises—amnesias, fugues, multiple personalities—tend to be more common than neurological ones like the seizures, paralyses, and sensory losses that were in vogue a century ago.
As for the epidemic, it emerged when patients under Charcot’s supervision at the Salpêtrière hospital in Paris began to display convulsive contortions during his rounds. (…) Over time, the numbers of patients with the symptoms grew. New constellations of spasms and convulsions developed among them (…)
Fourth, the more attention is paid to a behavior, the more the behavior is seen; the less attention is paid, the less it is seen.