BHS 49907 Memory and Amnesia

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BHS 499-07Memory and Amnesia

• Memory and Reality

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Source Monitoring

• Source monitoring the ability to keep track of
  where a memory came from.
• Accurate source judgments can be made on partial
  or vague information using familiarity.
• Source is integrated into the memory trace.
• The search for source information is controlled
  by prefrontal lobes whereas retrieval involves
  temporal lobes.

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Types of Source Information

• Several criteria are used to make judgments about
  the source of information
• Perceptual information
• Contextual information
• Expectedness of the source
• Semantic detail or affective information
• Cognitive operations during original experience

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Types of Source Monitoring

• Internal distinguishing what you thought about
  doing from what you actually did.
• External distinguishing between two external
  sources (who said what?)
• Reality monitoring distinguishing memories of
  what really happened from what was imagined.

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Source Monitoring Errors

• Information about source grounds memories in
  reality.
• Repeated attempts to remember can increase
  likelihood of confusing a real event with an
  imagined one.
• Repeated attempts to remember introduce
  perceptual qualities to the memory through
  imagination, making the memory seem real.
• Choices distort memories for qualities.

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Source Cueing

• Source cueing when the source is used as a
  retrieval cue to aid memory.
• Knowledge about the source can be used to narrow
  down choices during recall.
• Timbre is a perceptual quality of the source of a
  melody that can identify the instrument played
  and aid memory for the song itself.

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Cryptomnesia

• Not all plagiarism is intentional.
• Cryptomnesia when a person recalls a previously
  encountered idea without realizing the original
  source.
• The idea is mistakenly believed to be an original
  thought.
• This is a reality monitoring failure the source
  is lost or was never encoded.

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False Fame

• Familiarity increases when information is
  repeatedly presented.
• False fame effect the tendency to think someone
  is famous because their name sounds familiar.
• Unfamiliar names previously viewed on a list were
  considered more famous the next day.
• There is a preference for the familiar.

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Sleeper Effect

• When we first encounter information, the
  credibility of the source affects our acceptance
  of it.
• Later, when the source is forgotten, the
  information may gain (or lose) credibility
  compared to when first received.
• Conditions for the effect (1) attention to the
  info (2) source presented second (3) must rate
  trustworthiness immediately afterward.

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False Memories

• False memory when people recall something that
  never happened.
• Deese-Roediger-McDermott Paradigm for creating
  false memories
• Present a list of words associated with another
  word that is not presented, e.g. sleep.
• On testing, people are likely to recall sleep.
• Associations prime the not-presented word.

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Conditions for False Memory

• The more associations, the more likely the false
  memory will occur.
• The less recallable the actual items are, the
  more reconstruction is needed and the more likely
  a false memory.
• More likely with partial or fuzzier recall.
• Pictures less likely to show the effect.

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Influences on False Memory

• When people are directed to forget the list,
  false memory goes up.
• Part-set cueing is extended to the not-presented
  word, so false memory goes down.
• If the not-presented word is more emotional,
  false memory declines.
• Influenced by conformity expectation.

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False Memory from Integration

• Information from different points in time becomes
  integrated into a single memory.
• Several things are misremembered as the same
  event.
• Bransford Franks overlapping content is more
  likely to be integrated.
• Ants ate sweet jelly on the table.

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Implanted Memories

• Loftus deliberately planted false memories in
  people.
• The content of a question about the past becomes
  part of what is later remembered.
• The more plausible the information, the more
  likely it will be implanted, but the implausible
  can be implanted.

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Imagination Inflation

• Imagining an event, real or false, increases
  confidence in the memory for that event.
• Viewing pictures makes false memory more likely.
• Students can develop their own false memories by
  answering questions they know to be false.

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Qualities of False Memories

• True memories are more often
• Richer in detail, more emotional
• More likely to be recollected field memories.
• False memories are more often
• Stereotypical events
• Known observer memories
• These qualities cannot be used to distinguish the
  true from false because of overlap.

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Hypnosis Memory

• Hypnosis an altered state of consciousness in
  which a person is more willing to accept follow
  suggestions.
• People vary in hypnotizability.
• Hypnotic amnesia is a recent phenomenon induced
  by expectations.
• Amnesia was not part of hypnosis until 20th
  century.

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Early Hypnotists
Mesmer (1779)
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Inducing Hypnosis
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Accuracy of Hypnotic Recall

• People report more memories while hypnotized, but
  are less accurate.
• The increased info may be no different than what
  occurs with repeated questioning without
  hypnosis.
• Along with more information, more intrusions
  (false info).
• Hypnotized subjects are more easily fooled.

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Everyday False Memories

• Verbal overshadowing memories change as we talk
  about them.
• 64 recalled robber without narrative, 38
  percent with narrative
• Revelation effect slowly revealed info can
  cause new info to be judged as old.
• Slow revelation generates familiarity
• A lengthy memory recovery process can add a sense
  of familiarity to what is described.