by Paul R. McHugh

About the author: Paul R. McHugh is director of psychiatry at Johns Hopkins University School of Medicine in Baltimore, Maryland.

Where’s hysteria now that we need it? With the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), psychiatrists have developed a common language and a common approach to diagnosis. But in the process of operationalizing diagnoses, we may have lost some concepts about patient behavior. The term “hysteria” disappeared when the third edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III) was published in 1950; without it, psychiatrists have been deprived of a scientific concept essential to the development of new ideas: the null hypothesis. This loss hits home with the epidemic of multiple personality disorder (MPD).

The work of Talcott...