Dissociative Identity Disorder

Question 1

What is Dissociative Identity Disorder (DID)?

Answer 1

• An individual with two or more personalities (alters) that have their own unique behaviours, memories and relationships

Question 2

What is the DSM V criteria for DID?

Answer 2

• Disruption of identity characterised by two or more personality states (alters)
• At least two alters recurrently control behaviour
• One alter has an inability to recall personal information
• Symptoms are not due to medication or cultural/religious practice

Question 3

Describe epidemiology for DID

Answer 3

• Prevalence is hugely variable
• Sar et al (‘02, ‘03) found 12-13.8% in psychiatric outpatients
• Sar et al (‘14) found almost half (45.2%) of adolescent patients had a dissociative disorder with 16.4% diagnosed with DID
• More commonly found in women
• Rarely diagnosed until adulthood

Question 4

What mental disorders are comorbid with DID?

Answer 4

• PTSD
• Major depression
• Substance abuse
• Somatic symptoms (physical)
• BPD
• Phobias

Question 5

What are the two major theories in DID?

Answer 5

• Sociocognitive model

- Postraumatic model

Question 6

Describe the sociocognitive model

Answer 6

DID is a form of role play in suggestible individuals brought on by therapist either explicitly or implicitly (Iatrogenesis) (false memories)

Question 7

Describe the posttraumatic model

Answer 7

DID is a result of severe psychological and/or sexual abuse in childhood

Question 8

What evidence is there to support the sociocognitive model?

Answer 8

Pope et al (‘06) found:
- no reports of DID before 1800
- major increases since 1970
- Thought to be because of increased awareness due to popular culture (three faces of Eve, Sybil)
Acocelia (‘99):
- Women hospitalised for depression, therapist used suggestive questions and diagnosed DID
- McNally (‘03); patients have sued therapist for implanting false memories
- Californian hillside murderer; used DID as plea
- Spanos et al (‘85); showed DID can be role played study in students (fake hypnotised), we are very suggestible

Question 9

What does the sociocognitive model (Reiber, ‘06) say about discovery of Sybil?

Answer 9

• Sybil never presented with DID symptoms
• Psychiatrist encouraged multiple personalities which Sybil later revealed
• Psychiatrist gained fame and money
• No documentations of childhood abuse
• Transcripts of therapy show abuse was constructed

Question 10

Explain sociocognitive views on DID

Answer 10

• Iatrgenesis; multiple personalities occur during treatment
• Diagnosis differs with clinician; not many experts
• Thigpen & Cleckley (‘84) argue out of thousands of cases other than Eve they have only seen one other case

Question 11

What is the sociocognitive evidence for false memory in DID?

Answer 11

Porter et al (‘99) - implanted false memories in students using guided imagery

Lasko et al (‘04) - Same phisiological arousal between false memories and real memories. Particpants believe false memories (alien abductions)

Huntjen et al (‘03) - People report no sharing of memory between alters in explicit tests but show similar memory between alters compared to controls in implicit tests

Huntjen et al (‘12) - Tested autobiographical memory in DID patients. Interidentity amnesia again not supported, transfer between implicit tests

Question 12

What are the causes of DID according to the posttraumatic model?

Answer 12

• almost all cases of DID report severe CSA

- dissociation is a means of coping with trauma

Question 13

What evidence is there for posttraumatic model?

Answer 13

Kisiel & Lyons (‘01) - Children who dissociate are more likely to develop psychological symptoms. Created child dissociative checklist

Taylor & Martin (‘44) - reviewed DID cases before it was widely known about, inconsistent with sociocognitive model

Lewis ('99) :-
- 20 year study into 150 murderers
- Trances in childhood
- Imaginary friends
Corroborated by third parties
- Distinct handwriting of alters (expert opinion)

Question 14

What evidence is there for posttraumatic model of memory deficits?

Answer 14

• Putnam (‘95) suggest amnesia for traumatic events are defense mechanism.
• Adreano & Cahill (‘06) found stress hormones can interfere with memory formation
• Neisser & Harsch (‘91) found particpants memory recall of a specific disaster was grossly inaccurate 2 years later compared to 1 day recall

Question 15

What is the neurobiological evidence for DID?

Answer 15

• MRI study, smaller volume of hippocampus and amygdala, however highly comorbid with PTSD
• Stmulation of hippocampus produced dissociative symptoms
• Ketamine (atagonist of NDMA receptors concentrated in hippocampus produce dissociative symptoms

Question 16

What are cticisms of the posttraumatic model?

Answer 16

• Little evidential support between trauma and dissociation (Lynn, ‘12)
• Dissociation is not entirely environmental but a heritable trait (Jang, ‘98)
• Psychopathology often asscoiated with an inability to forget (Lynn, ‘12)

Question 17

What did Dell (2006) find in opposition to the sociocognitive model?

Answer 17

• Argued DSM is too narrow
• Found two kinds of dissociation:-
  partly unconscious/dissociated (child voices, internal struggle) and fully unconscious/dissociated (Time loss, Being told of actions)