The theory of conversion disorder stems from ancient Egypt, and was formerly known as "hysteria". The concept of conversion disorder came to prominence at the end of the 19th century, when the neurologists Jean-Martin Charcot and Sigmund Freud and psychologist Pierre Janet focused their studies on the subject. Before their studies, people with hysteria were often believed to be malingering.[1] The term "conversion" has its origins in Freud's doctrine that anxiety is "converted" into physical symptoms.[2] Though previously thought to have vanished from the west in the 20th century, some research has suggested that conversion disorder is as common as ever.[3]