MULTIPLE PERSONALITY

MULTIPLE PERSONALITY

Primary Disciplinary Field(s): Clinical Psychology, Psychiatry, Abnormal Psychology

1. Core Definition and Diagnostic Context

Multiple Personality, historically known as MPD, refers to a severe and rare form of dissociative reaction characterized by the presence of two or more relatively independent, organized personality systems within the same individual. This condition involves a profound failure to integrate various aspects of identity, memory, and consciousness. While the disorder has historically garnered significant public and media attention, early psychiatric records suggest that the incidence of documented cases was extremely low, with estimates placing the historical count at around one hundred verified instances. Subsequent revisions to psychological nomenclature and diagnostic criteria have led to the formal relabeling of this condition as Dissociative Identity Disorder (DID) in authoritative references such as the Diagnostic and Statistical Manual of Mental Disorders, reflecting a conceptual shift away from the idea of distinct personalities and towards the recognition of fragmented self-states.

The core feature of MPD is not merely having conflicting feelings or tendencies, which are considered normal human experiences, but the development of fully formed, separate systems of self that operate autonomously. These systems, often referred to as “alters” in modern clinical language, function with established boundaries, memory systems, and affective profiles that are strikingly distinct from the primary, or “host,” personality. The existence of these separate systems represents a catastrophic failure of psychological integration, forcing the individual into a state where different parts of the self handle incompatible urges or traumatic memories by compartmentalizing them into separate entities.

2. Historical Context and Nomenclature

The concept of multiple personality gained prominence in the late 19th and early 20th centuries, though documented cases remained exceedingly rare. The disorder’s highly dramatic presentation made it a fixture in popular culture, which often exaggerated its frequency and severity, contributing to its status as a “highly publicized disorder.” Despite the public fascination, clinical consensus remained cautious regarding its prevalence. The historical name, “Multiple Personality,” implies that several complete, integrated individuals share one body, which clinicians increasingly recognized as an inaccurate representation of the underlying pathology.

The modern shift to the term Dissociative Identity Disorder (DID) reflects an understanding that the disorder involves a lack of coherence and integration within a single identity structure, rather than the coexistence of multiple fully autonomous personalities. Dissociation, in this context, is the primary defense mechanism, allowing the individual to involuntarily separate or compartmentalize traumatic memories or unacceptable behavioral urges from ordinary consciousness. This mechanism serves as an unconscious solution to acute internal conflict, though it ultimately results in chronic internal warfare and fragmentation.

3. Clinical Presentation: Characteristics of Altered States

The alternate personality systems developed within the individual are characterized by their remarkable distinctness and complexity. Each secondary personality possesses its own well-developed suite of psychological characteristics, including characteristic emotional reactions, specific thought processes, discernible behavior patterns, and unique mannerisms. These differences are often so profound that they manifest externally in tangible ways, lending credence to the idea that these are indeed separate systems operating independently.

The differences between the primary and secondary personalities often extend to biographical and physical markers. Secondary personalities frequently adopt different names, may choose to wear specific styles of clothing, and often exhibit unique handwriting styles that diverge significantly from that of the primary personality. Furthermore, the psychological profiles of the alters are frequently polar opposites, serving to contain incompatible aspects of the self. For example, one personality might be strictly inhibited, while another is uninhibited; one might be timid, while another is overtly aggressive; or one might exhibit extreme thrift, while another is defined by extravagance, even practicing behaviors that would be considered morally or socially forbidden by the primary self.

The process of shifting between these personality systems, known as “switching,” is typically sudden and occurs without warning. The duration of time spent in any one personality state is highly variable, ranging from brief episodes lasting only a few minutes to sustained periods that may last for several years. This unpredictable and involuntary switching significantly disrupts the individual’s sense of self, continuity of memory, and ability to function consistently in daily life, underscoring the severity of the dissociative break.

4. Mechanisms of Dissociation and Etiology

The development of multiple personality is considered a gross exaggeration of normal psychological processes related to internal conflict. Most individuals possess conflicting tendencies—such as competing desires or opposing moral urges—which are generally harnessed and integrated into a flexible, functional personality structure, often becoming a source of creativity and adaptive adjustment. However, for those susceptible to MPD, particularly when subjected to severe psychological stress or trauma, the urges become so acutely incompatible that they fail to adjust or integrate these disparate tendencies.

In response to this intolerable internal conflict, the individual unconsciously adopts a drastic defensive solution: the unacceptable or incompatible side of the personality is psychologically “cut away” and molded into a separate self. This separate self appears to act autonomously, allowing the individual to put forbidden urges into practice without the primary personality experiencing the usual tension, anxiety, or guilt that would otherwise result. This mechanism effectively allows the individual to “eat their cake and have it too,” externalizing the guilt onto the separate personality system.

5. Dynamics of Switching and Co-Consciousness

A defining dynamic of MPD involves the degree of mutual awareness between the different personality systems. Generally, the two or more personalities are unaware of each other’s existence, resulting in significant memory gaps for the primary self regarding the actions performed by the secondary self. This mutual amnesia is the standard presentation of the disorder.

However, in certain clinical presentations, a phenomenon known as “co-consciousness” is observed. In this scenario, the secondary, or “co-conscious,” personality possesses awareness of the thoughts, emotions, and reactions of the primary, dominant personality. In this asymmetrical relationship, Personality B knows everything about Personality A, but Personality A remains completely ignorant of B’s existence or activities. This co-conscious personality may subtly or overtly indicate its awareness of the primary self. This can manifest through indirect communication, such as automatic writing, or through mischievous, deliberate actions intended to disrupt the primary self’s life, such as charging extravagant and unauthorized purchases to the primary personality at a department store.

6. Differential Diagnosis: MPD vs. Schizophrenia

It is crucial, both historically and clinically, that Multiple Personality be accurately differentiated from schizophrenia, as the two are frequently confused, partly due to the misleading literal translation of schizophrenia as “split personality.” Despite the semantic confusion, the nature of the “split” in each disorder is fundamentally different and relates to distinct domains of psychological functioning.

In Multiple Personality (DID), the split occurs between different total, functioning personality systems. The individual develops separate identities that operate independently of one another. Conversely, in schizophrenia, the split is not between different personalities, but between different processes within the same personality structure. Schizophrenia involves a profound disorganization and fragmentation wherein the individual’s thought processes, motor activity, and emotions become fundamentally disjointed and at odds with one another, leading to psychotic symptoms, disorganized speech, and impaired reality testing, which are absent or secondary in MPD.

7. Therapeutic Approaches and Goals

The ultimate objective of therapy for individuals diagnosed with Multiple Personality is integration, which represents the complete association of the previously separate personality systems back into a single, cohesive identity. The goal is to move away from dissociation and disintegration toward a unified self. The foundational requirement for successful integration is achieving mutual awareness, meaning the secondary personality must be brought fully to the conscious awareness of the primary personality, thereby ending the unilateral amnesia.

This process is often facilitated by special therapeutic techniques designed to bypass the defensive barriers between the alters. These techniques commonly include the use of focused, sustained hypnotic suggestion, which can lower cognitive defenses and allow for direct communication. Additionally, interviews conducted under the influence of certain pharmacological agents, such as sodium amytal (often referred to as a “truth serum”), have historically been employed to relax defenses and enable the personality systems to communicate and share previously walled-off memories. When these techniques are effectively applied and the personality systems can achieve communication and reconciliation, the prognosis for successful integration is generally optimistic.

Further Reading

• Dissociative Identity Disorder (Wikipedia)
• Schizophrenia (Wikipedia)
• Hypnotic Suggestion (Wikipedia)
• Ego Integration (Wikipedia)