Dissociative disorders, most notably multiple personality disorder, remain mysterious and misunderstood. Dramatic stories of patients who claim to have personalities from past generations, or even of animals, do little to enhance the scientific appreciation of the substance of these disorders. From what we see in Lockhart (see page 11), this does impact on courts' appreciation of criminal responsibility.
Researchers at the Menninger Clinic, using the Dissociative Experiences Scale (DES), explored how dissociative states are conducive to psychotic symptoms (Comprehensive Psychiatry, Vol. 38:6 pp. 327-334). They found that severe dissociative detachment, by virtue of loosening the moorings in inner and outer reality, promotes psychotic symptoms and personality decompensation.
Study subjects were 266 women in inpatient treatment for severe trauma-related disorders. All completed the DES and 102 also completed the Millon Clinical Multiaxial Inventory (MCMI-1II). The DES is a 28-item self-report instrument using visual analog response scales: for each item, respondents make a mark along a 100-mm line from 0% to 100% indicating the extent to which they experience a symptom. The MCMI-III is a 175-item, true-false inventory with 14 personality scales, 10 clinical syndrome scales, and 3 validity scales.
The high-trauma-history clinical sample scored extremely high on the DES, revealing a substantial population of "high dissociators." DES factors most representative of dissociation were: feel that body does not belong; feel that people, objects, world not real; feel as if two different people; feel as though watching self as if another person; find self in place with no idea how got there; find new things do not remember buying; told do not recognize friends or family members on certain occasions.
Factor analysis of the DES yielded two dimensions of dissociative detachment: detachment from one's own actions and detachment from the self and the environment. Each of these DES dimensions relates strongly to the thought disorder and schizotypal personality disorder scales of the MCMI-III. The researchers note that the severity of dissociative symptomatology as measured by the DES correlates substantially with the psychoticism scales on a range of psychometric tests. Severe dissociative detachment renders persons vulnerable to psychosis not only because it deprives them of external anchors, but because it robs them of internal anchors—the sense of being connected to one s body. Increasingly detached from the controls and stabilizing influences of repetitive, though ordinary, human affairs; they may lose their sense of behavioral propriety. In states of extreme dissociative detachment, individuals lose their moorings in inner and outer reality. Descriptively, they become psychotic.
This research has important implications for criminal responsibility and the insanity defense. Traditionally, examiners have explored for histories of schizophrenia and bipolar illness. But with the DES showing measurable association with psychosis, additional options for major mental diseases in the criminal court may be legitimately considered.
