[Psychogenic movement disorders in the mental handicapped. Differential diagnosis and therapy. Case report].

The problems involved in treating psychogenic movement disorders in mentally retarded persons are pointed out. A psychoanalytic approach is doomed to failure because of the mental handicap. The authors report positive therapeutic results with a 17-year-old girl who had a severe hysterical movement disorder including sudden falls and a grotesque gait. Successful behavior therapy with this patient supports the hypothesis that conditioning was the chief factor in the maintenance of the symptoms and indicates that even severe mental retardation does not necessarily imply that there will be resistance to extinction. The individuals of greatest significance to the patient should, in the author's view, play an important part in the treatment program.