Medically Unexpained Symptoms: Amnesia

Michael Kopelman

Psychological forms of Memory Disorders

1. Global:

Entire earlier life + personal identity (‘self’)

e.g. ‘Fugue state’ - transient

Psychogenic focal retrograde amnesia - persisting

2. Situation-specific:

‘Gaps’ in memory for specific events:

e.g. P.T.S.D. (Post-Traumatic Stress Disorder).

Victims of crime e.g child sexual abuse, rape

Perpetrators of crime e.g homicide

PSYCHOGENIC FUGUE STATE

Syndrome consisting of:

1. Sudden loss of memory

2. Involving loss of autobiographical memories and the sense of

personal identity.

3. Usually associated with a period of wandering.

4. Normally lasts a few hours or days only (up to about 3-4 weeks).

5. Subsequent amnesic gap on recovery for the period of ‘fugue’.

6 If the amnesia persists Psychogenic Focal Retrograde Amnesia.

PREDISPOSITIONS TO FUGUES

1. Severe precipitating stress

- marital

- financial

- bereavement

- offence

- war

2. Depressed mood + suicidal ideas

3. Past history of a transient ‘neurological’ amnesia

- head of injury

- alcohol ‘blackout’

- epilepsy

(Kopelman, 1987: see also Brain, 2002)

‘Focal Retrograde Amnesia’

• Term coined by Narinder Kapur (1993).

• Strictly, R.A. in the absence of any anterograde memory loss.

• Sometimes, initially accompanied by a transient loss of personal identity

• Unlike ‘fugue state’, the memory disorder persists

• Often (but not always) follows mild concussion or other cerebral event.

• Usually has been assumed to reflect underlying brain pathology.

• Brain imaging usually normal.

• Some reported cases in the literature are not in fact ‘focal’

• Others may well be psychogenic (Kopelman,2000).

PSYCHOGENIC FOCAL RETROGRADE AMNESIA

COMPARISON and DIFFERENTIATION OF FUGUE /

PSYCHOGENIC AMNESIA versus T.G.A. / T.E.A.

• In both:

- Can be preceded by precipitating stress / significant life-event.

- Standard investigations (routine EEG, CT, MRI) can be normal.

• Differentiation:

- Loss of personal identity in fugue

(never in 114 cases of TGA: Hodges and Ward, 1989).

- Repetitive questioning in TGA / TEA

(seldom in fugue/psychogenic, where may get ‘la belle indifference’)

- Other signs eg. sensorimotor in TEA, wandering in fugue.

- ‘Temporal gradients’ of retrograde amnesia.

MANAGEMENT OF SUCH CASES:

• Make the diagnosis!

• Engage the patient sympathetically: no use confronting.

• Don’t rush in with interview under sedation: may be more useful later.

• But get as much information as possible: subtle detective work.

• Emphasise disadvantages of amnesia and advantages of confronting

underlying problems and offer help with these. Engage family members

• If amnesia well entrenched / long-standing and family enmeshed in

system - very hard to shift.

Treat any underlying depression.

SOCIAL FACTORS & BRAIN SYSTEMS INFLUENCING MEMORY RETRIEVAL & PERSONAL IDENTITY:

Kopelman , Brain (2002)

SOCIAL FACTORS & BRAIN SYSTEMS INFLUENCING MEMORY RETRIEVAL & PERSONAL IDENTITY:

Kopelman , Brain (2002)

NEUROIMAGING CORRELATES OF MEMORY SUPPRESSION

Anderson

et al., 2004

At least TWO ROUTES TO

PSYCHOGENIC FOCAL RETROGRADE AMNESIA

Head injury

/cerebral ‘event’

(may be mild)

Fugue episode:

not treated appropriately

/ behaviour reinforced

Predisposing

psychological factors

Predisposing

psychosocial

factors

(Persisting) Focal Retrograde Amnesia

53 cases of Psychogenic Amnesia:

preliminary findings

Federica Corno, Kim Friedner, Sarah Casey, Neil Harrison, Kate Johnston,

Eli Jaldow, Michael Kopelman

53 cases of Psychogenic Amnesia:

• Psychogenic Fugue N=16

• Fugue-like Focal retrograde amnesia N=16

• Psychogenic focal retrograde amnesia N=16

eg after minor head injury

• Gaps in memory N=5

Total N=53

Review of case records and neuropsychological test scores

Summary

• In fugue, the memories return – normal: personal semantic facts

-- near-normal: episodic incidents

• Lesser (and variable) improvement in F.R.A.

-- reversed temporal gradient still

• Consistent with memory inhibition.

Levels of awareness

in psychogenic memory loss:

- Deliberate or unconscious mechanism?

Psychogenic fugue /Focal retrograde amnesia cases:

• Very difficult / impossible to know the extent to which people

are deliberately avoiding painful / difficult memories or

the extent to which that this is a ‘truly’ unconscious

process.

• “It’s like a box locked away and I don’t really want to open it.”

• “I put things in boxes. I choose to put them in the back of my mind.

I’ve always done that. I know the memories are there…but (I)

cannot get access to them.”

Conclusions:

• Psychogenic amnesias can be interpreted at different levels

- cognitive, neurophysiological, or psychodynamic.

• They involve the avoidance of painful / unpleasant memories

- may involve varying degrees of conscious awareness.

• Frontal inhibitory control mechanisms may well be implicated

- some functional imaging support for this.