INTRUSIONS, DISTORTIONS AND ILLUSORY MEMORIES

• The “fundamental attribution error” in memory

– When I was younger, I could remember anything, whether it had happened or not; but my faculties are decaying now and soon I shall be so I cannot remember any but the things that never happened.- Mark Twain's Autobiography

– It’s never too late to have a happy childhood.

- Shel Silverstein, author of Where the Sidewalk Ends

– How do you know a memory is real?

• Intrusions, False alarms and misidentification– Similarity-based errors in recall and

recognition (typically meaning-based)– Cases of false identification

• Demjanjuk as Ivan the Terrible (Wagenaar, 1988)

• Demand characteristics of lineups• Consulting on an EW case

• Distortion and confabulation– Event (at encoding) or Cue (at retrieval)

activates related semantic and episodic information that gets integrated into episode• War of the Ghosts (Bartlett, 1932)• Nancy & the Doctor (Owens et al. 1979)

• Historical vs. Narrative Truth (Spence, 1984)

• Increasing vulnerability over time

– Reder (1982): Ss read short stories:

• [hamburger heir]– Speed of “studied” versus “plausible”

decisions shifts over time:

– “Fuzzy trace theory” (Brainerd & Reyna)• Encoding includes both verbatim and

“gist” information• Verbatim, as “superficial,” is less

distinctive and more vulnerable to forgetting

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• Source amnesia– Cue activates correct target, wrong

context• the misinformation effect (Loftus, 1985)• The famous-overnight effect (Jacoby,

1989)• Verbal overshadowing (Schooler ’90)

– Failure to distinguish experienced from imagined events

• Failures of reality monitoring (Johnson, 1985)

• The false memory studies– Roediger & McDermott : How sweet

it is (1995)– Loftus & Ketcham: Lost in a shopping

mall (1994)• Hypnosis and confabulation

– Evidence that hypnosis changes bias, not sensitivity

– Increases in confidence– Accepting of sometimes bizarre

“memories” as fact

Delusions and confabulations in memory disorders

• Etiology– Often associated with frontal lobe damage

• Rupture of anterior arteries• Korsakoff’s syndrome• Frontal degenerative diseases

• Symptoms– Intensity, frequency, plausibility of

confabulations vary widely

– Content is often based on “real” episodes

– Not an obligatory “gap filling”

– May be believed obsessively despite acknowledged contradictions

• Theory– Loss of “executive control” over memory and

metamemory functions

– Impairment of memory for temporal order and context

– Loss of “reality monitoring” and increase in source amnesia

– Consolidation of false memories with rehearsal

• Some case studies

• The case of John Demjanjuk– Ukranian immigrant, auto worker in

Cleveland– On KGB list of German “war criminals” – Exported and convicted in Israel of being

“Ivan the Terrible” of Treblinka, 1988– Survivors confidently identified him as

Ivan – Fall of USSR, KGB docs forgeries, 1991– Acquitted and released, 1993– Charged with similar crimes at other

camps, 1999– stripped of U.S. Citizenship and slated for

deportation to Ukraine, 2005

“I said the photo was not particularly sharp. It was older than the Ivan I knew, but it was still him. The frame, the round face, the short neck, the wide shoulders and the protruding ears. I told them this is the Ivan I remember,” Epstein said. (Reuters, 23 February 1987.)