Geri Anderson

Patterns of dissociation in clinical and nonclinical samples

Research has consistently found elevated mean dissociation scores in particular diagnostic groups. In this study, we explored whether mean dissociation scores for different diagnostic groups resulted from uniform distributions of scores within the group or were a function of the proportion of highly dissociative patients that the diagnostic group contained. A total of 1566 subjects who were psychiatric patients, neurological patients, normal adolescents, or normal adult subjects completed the Dissociative Experience Scale (DES). An analysis of the percentage of subjects with high DES scores in each diagnostic group indicated that the diagnostic groups mean DES scores were a function of the proportion of subjects within the group who were high dissociators. The results contradict a continuum model of dissociation but are consistent with the existence of distinct dissociative types.

Differences between multiple personality disorder and other diagnostic groups on structured interview

The Dissociative Disorders Interview Schedule was administered to 20 subjects with multiple personality disorder, 20 with schizophrenia, 20 with panic disorder, and 20 with eating disorders. The findings showed that multiple personality can be differentiated from the other groups on variables such as history of physical abuse, sexual abuse, substance abuse, sleepwalking, childhood imaginary playmates, secondary features of multiple personality and extrasensory and supernatural experiences. Those with multiple personality also differ from the other groups on DSM-III criteria for multiple personality, psychogenic amnesia, and psychogenic fugue. The groups did not differ on the number of subjects who had had a major depressive episode.

Schneiderian symptoms in multiple personality disorder and schizophrenia

We report structured interview data from a series of 102 cases of multiple personality disorder (MPD) diagnosed in four centers. Schneiderian first-rank symptoms of schizophrenia were equally common in all four centers. The average MPD patient had experienced 6.4 Schneiderian symptoms. When these 102 cases are combined with two previously reported series of MPD cases, an average of 4.9 Schneiderian symptoms in 368 cases of MPD is noted. This compares with an average of 1.3 symptoms acknowledged by 1,739 schizophrenics in 10 published series. Schneiderian symptoms are more characteristic of MPD than of schizophrenia.

Abuse histories in 102 cases of multiple personality disorder

The authors interviewed 102 individuals with clinical diagnoses of multiple personality disorder at four centres using the Dissociative Disorders Interview Schedule. The patients reported high rates of childhood trauma: 90.2% had been sexually abused, 82.4% physically abused, and 95.1% subjected to one or both forms of child abuse. Over 50% of subjects reported initial physical and sexual abuse before age five. The average duration of both types of abuse was ten years, and numerous different perpetrators were identified. Subjects were equally likely to be physically abused by their mothers or fathers. Sexual abusers were more often male than female, but a substantial amount of sexual abuse was perpetrated by mothers, female relatives, and other females. Multiple personality disorder appears to be a response to chronic trauma originating during a vulnerable period in childhood.

Somatic Symptoms in Multiple Personality Disorder

A structured interview, the Dissociative Disorders Interview Schedule, was administered to 20 patients with multiple personality disorder, 20 with panic disorder, 20 with eating disorders, and 20 with schizophrenia. The frequencies of somatization disorder and of individual somatic symptoms in the four groups were compared. The multiple-personality patients reported more somatic symptoms than the other groups. Of the 20 multiple-personality patients, seven met the criteria for somatization disorder. The average number of somatic symptoms per multiple-personality patient was 13.5.

Phenomenological Overlap of Multiple Personality Disorder and Obsessive-Compulsive Disorder

Three patients with multiple personality disorder and three with obsessive-compulsive disorder were compared on a variety of self-report measures and on two structured interviews. Amytal Sodium interviews had been conducted on the obsessive patients; alter personality-like entities claiming responsibility for the obsessions and compulsions were contacted in two patients. The one obsessive patient with no alter personality differed markedly from the other five on the SCL-90, the Lynfield Inventory, and the Dissociative Experiences Scale. Structured interviews with the Anxiety Disorders Interview Schedule and the Dissociative Disorders Interview Schedule also clearly differentiated this patient from the other five. It appears that there is a phenomenological overlap between multiple personality disorder and some cases of obsessive-compulsive disorder. Obsessive patients with prominent dissociative features may be a psychologically and biologically distinct subgroup.

Differentiating multiple personality disorder and complex partial seizures

A number of reports have suggested that some cases of multiple personality disorder might be due to temporal lobe epileptic discharges. We have administered a structured interview, the Dissociative Disorders Interview Schedule, to 20 subjects with multiple personality disorder, 20 with complex partial seizures, and 28 neurologic controls. Subjects also completed the Dissociative Experiences Scale. Results show that multiple personality can be differentiated from complex partial seizures on a large number of items. The seizure patients did not differ from controls. The data indicate that the phenomenologies of these two disorders are distinct, and, therefore, there is little reason to assume a common etiology.

Dissociative experiences among psychiatric inpatients.

The Dissociative Experiences Scale was administered to 299 inpatients on an acute care general adult psychiatric ward over a 2-year period. The average score was 14.6, which is significantly higher than the mean for the general population. About one in six inpatients reported very high scores above 50 on the seven most common items in the scale, indicating a high level of dissociative psychopathology. Based on the responses to four items which form a scale factor called Activities of Dissociated States, an estimate is made that 6%-8% of general adult inpatients may have multiple personality disorder. Dissociative psychopathology is common on inpatient units.