Medical Definition of Hysteria

Copyright © 1996-1997 Merck & Co., Inc., Whitehouse Station, NJ, USA. All rights reserved.

SECTION 12. PSYCHIATRIC DISORDERS
140. THE NEUROSES
HYSTERICAL NEUROSIS
(Conversion Reaction; Conversion Disorder; Dissociative Reaction; Dissociative Disorder)

A neurotic disorder characterized by a wide variety of somatic and mental symptoms resulting from dissociation, typically beginning during adolescence or early adulthood and occurring more commonly in women than men. Since the concept of hysteria as a disease is over 2000 yr old, its limits as a disorder have become blurred by a variety of definitions. Discussion is restricted to those phenomena classified as conversion and dissociative disorders of consciousness, which have a common basis in the mental phenomenon of dissociation.

HYSTERICAL NEUROSIS - Etiology

The concept of dissociation, a process whereby specific internal mental contents (memories, ideas, feelings, perceptions) are lost to conscious awareness and become unavailable to voluntary recall, is central to an understanding of the genesis of hysterical symptoms. Though unconscious, these mental contents can be recovered under special circumstances (eg, in dreams or a hypnotic trance). Furthermore, they are able to affect the individual's awareness and behavior in a variety of ways. For example, the dissociation and loss from consciousness of memories of motor patterns lead to paralysis; the emergence of a fragment of a dissociated visual memory may produce an ego-alien visual hallucination; the emergence of a complex of mental associations forming a dissociated personality may effect a complete change in the individual's behavior. All phenomena of conversion and dissociative hysteria may be viewed as the effects of either the dissociation itself or the eruption into consciousness of portions of the dissociated mental contents of varying degrees of complexity. Proneness to dissociation may in part be genetic.

Two special aspects of dissociation should be noted: (1) It is closely correlated with hypnotizability, and individuals prone to spontaneous dissociation usually rate high on hypnotizability scales. (2) It may serve as a psychologic defense; ie, it provides a mechanism for banishing unpleasant, painful, and anxiety-provoking mental contents from consciousness. Recent clinical studies point to the particularly frequent presence of memories of major aggressive and sexual child abuse in patients with multiple personality disorders.

HYSTERICAL NEUROSIS - Symptoms and Signs

Conversion symptoms: Almost any organ disease symptom can be simulated on an hysterical basis; eg, symptoms mimicking the illness of a deceased relative. A variety of sensorimotor symptoms have been considered to be specific to and characteristic of hysterical neurosis. Weakness and paralysis of muscular groups are common; spasms and abnormal movements, less frequent. The motor disturbances are usually accompanied by altered sensibility, especially those involving touch, pain, temperature, and position sense. Especially characteristic are the "glove and stocking" distribution of the motor and sensory disturbances when these affect the limbs; ie, the distribution is determined by the body-image concept of a functional arm and leg rather than the dermatome innervation of the area affected. Another common distribution is complete hemianesthesia, which extends exactly to the midline of the body fore and aft. Less frequently, special senses and functions may be affected, such as in hysterical blindness, deafness, and aphonia; both visual and auditory hallucinations may occur.

Dissociative phenomena: A variety of altered states of consciousness may result from the dissociative process. In somnambulism, the patient appears to be out of contact with his environment, is seemingly unresponsive to external stimuli, and in many cases appears to be living out a vivid, hallucinated drama, often the memory of some past emotionally traumatic event. In amnesia, the most common form of dissociative hysteria, the patient typically has a complete loss of memory for all past events covering a period of several hours to several weeks. Anterograde amnesia may occur, wherein the amnesia covers the memory of events as they are experienced, the patient forgetting continuously from moment to moment what he has just been thinking, feeling, and doing. For a discussion of amnesia as a functional syndrome in organic cerebral disease.