Dissociative Identity Disorder is the name of the mental health condition which is present when several different alter identities (dissociated personality states/parts) can physically take control of someone’s body. [1, 2] It used to be called Multiple Personality Disorder. Other criteria also exist including amnesia and signs of clinically significant distress or impaired functioning. In Dissociative Identity Disorder (DID) the terms below are often used, these date back to when it was known as Multiple personality disorder:
- host – the alter (or alters) are in charge of the body most of the time. :xiii
- alter / alter identity – any identity other than the host :xiii
- fragment – a part without distinct or complete identity and not capable of functioning independently, fragments typically do a very specific job only or hold a particular part of a traumatic experience – e.g. the visual memory and knowledge of specific abuse with no recollection of the pain (which another fragment will hold). :xiii Fragments are not considered fully personality states for the purpose of diagnosis.
- polyfragmented DID – dozens of alters/personality states exist, usually with fragments as well. This is common in survivors of organized or ritual abuse and extreme abuse during the earliest years of childhood.
The current model used in understanding of DID
The terms currently used more accurately represent expert understanding of DID.  These terms are:
- ANP / Apparently Normal Part replaces the term ‘host’, focused on daily life and avoiding trauma reminders [3, 4]
- EP / Emotional Part All alters not focused on daily life, including those that hold trauma memories. 
- polyfragmented DID – a term still used with its original meaning, in effect describing large DID systems
Every person with DID has at least two ANPs – parts who appear totally “normal” in the sense of not repeatedly living in a state of trauma.  Typical jobs for ANPs would include continuing daily life “as normal” – i.e. cooking, cleaning, eating, sleeping, studying or working, and it is typically an ANP who would seek medical treatment or therapy if they felt it necessary. 
Fragments – The main job of a fragment is usually to hold unprocessed trauma memories. An EP is an elaborate fragment that holds trauma memories.
How do ANPs and EPs differ?
This artwork by Emma shows the different types of thoughts she experiences from her different personality parts. Which answers do you think may come from an ANP? Can you spot any that may be from an EP?
If you have DID or you know someone that has then use which ever terms or names feel most comfortable.
- Polyfragmented Dissociative Identity Disorder More on ANPs and EPs (traumadissociation.wordpress.com)
- More about Alters (traumadissociation.com)
- Dissociative Identity Disorder (traumadissociation.com)
- Structural Dissociation of the Personality and the Polyfragmented DID personality system (traumadissociation.wordpress.com)
- Dissociation: Checking out means missing out (traumaddissociation.wordpress.com)
- Braun, Bennett G. (1986). Treatment of Multiple Personality Disorder . American Psychiatric Pub, ISBN 0880480963.
- Haddock D, (2001). The Dissociative Identity Disorder Sourcebook. McGraw-Hill, ISBN 0737303948.
- Miller, Alison (2011). Healing the unimaginable: Treating ritual abuse and mind control. Karnac Books. ISBN 1780499094.
- The Haunted Self, (2006).
Kluft, R. P. & Fine, C. G. (1993). Clinical Perspectives on Multiple Personality Disorder. American Psychiatric Pub, ISBN 0880483652.
Miller, A. (2014). Becoming Yourself: Overcoming Mind Control and Ritual Abuse. Karnac Books. ISBN 1782412182.
Article revised June 2016.