Experience of Self › Disturbance of the Continuity of Self

Experience of Multiple Personalities

This is the rare and severe experience of feeling that one has more than one distinct, separate personality, each with its own way of being, rather than simply feeling like a different or changed version of oneself. It represents the most severe end of disturbance in the continuity and unity of self-experience, and is formally recognised as a diagnostic category in its own right.

This has traditionally been described as both rare and clinically controversial, with a differential diagnosis that includes other dissociative disorders, schizophrenia, bipolar disorder, borderline personality disorder, malingering, and complex partial epilepsy, reflecting how carefully this presentation needs to be assessed before being accepted at face value.

Also known as

Multiple personality disorder

The older diagnostic term, retained in ICD-10 within the category of dissociative and conversion disorders and described there as both rare and controversial.

Dissociative identity disorder

The DSM-5 diagnostic term, which emphasises a strong association with traumatic events such as childhood abuse.

Recognition features

• A description of experiencing more than one distinct personality, each with its own characteristics, rather than a single self that has changed over time
• A rare presentation, and one that warrants careful, thorough assessment given its overlap with several other conditions
• Frequently associated, per its DSM-5 description, with a history of significant trauma, particularly childhood abuse
• Distinct from milder, more common experiences of personal change or of feeling 'as if' one is two people in a single moment

Eliciting it at interview

• Take a careful, structured history of the experience, including how the different personalities are described, how distinct they feel from one another, and how long this pattern has been present
• Given the wide differential diagnosis, systematically screen for other possible explanations, including psychotic illness, bipolar disorder, personality disorder, and organic causes such as complex partial epilepsy
• Ask sensitively about early life experiences, including possible trauma, given the recognised association, while being mindful of the emotional weight such questions carry

Distinguishing features

• Differs from disturbance of self-unity, in which a person feels like two people at a single moment, often with retained 'as if' insight, whereas this involves distinct, separately experienced personalities, often without that qualification
• Differs from disturbance of self-continuity more generally, of which it represents the most severe and specific form, rather than a milder sense of having changed
• Requires careful differentiation from a range of other conditions with overlapping features, given its recognised diagnostic complexity and controversy

Common misconceptions

• That this is a common presentation; it is explicitly recognised as rare, and claims of multiple personalities warrant careful, thorough differential assessment rather than being assumed at face value
• That this is simply an extreme version of ordinary mood or identity fluctuation; it is a specific, formally recognised diagnostic category with its own defined features and differential diagnosis

Related phenomena

Disturbance of the Continuity of Self · Disturbance of the Immediate Awareness of Self-Unity

Practice this

A patient describes, and appears genuinely to experience, having several entirely distinct personalities, each with its own name, manner, and way of relating to the world, rather than simply feeling like a changed or different version of herself. What is this? · A patient describes sometimes acting or speaking in a way that feels automatic, as though driven by another part of herself, while readily acknowledging that this is just how it feels, not a literal belief that she is genuinely two separate people. Before revealing the answer: is this the experience of multiple personalities? · A patient describes an unusual experience of self. Before revealing the answer, decide what distinguishes the experience of multiple personalities from a disturbance of self-unity. · You suspect a patient is describing the experience of multiple personalities. Before revealing the answer, decide how you would assess for this. · Explain why the experience of multiple personalities requires careful, thorough differentiation from other conditions before being accepted as the diagnosis.

Illustration

A 35-year-old woman with a history of severe childhood trauma describes, over several detailed assessment sessions, distinct ways of being that she experiences as separate from one another, each with its own name, manner, and memories, a pattern that has been present in a consistent form for many years and that a thorough assessment does not better explain by another diagnosis.

References

• Casey, P. & Kelly, B. (2019). Fish's Clinical Psychopathology, 4th ed. Ch. 7, 'Disorders of the Experience of Self'.