This term is confined to the disorder attributed to the viral epidemic encephalitis that followed World War I. Virtually no cases have been reported since 1926. The condition, however, is differentiated from other encephalitis. It may present itself as acute delirium and sometimes its outstanding feature is apparent indifference to persons and events ordinarily of emotional significance, such as the death of a family member. It may appear as a chronic brain syndrome and is sometimes dominated by involuntary, compulsive behavior. If not of psychotic proportions, the disorder is classified under Non-psychotic OBS with intracranial infection.
As of DSM-III, this disorder is no longer part of the DSM.