HP502 Introductory Psychology Longterm Memory LTM, Retrieval

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HP502 Introductory Psychology Long-term Memory
(LTM), Retrieval Forgetting.

• Dr. Paula Mitchell Ext.9622
• Email p.mitchell_at_ballarat.edu.au

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Encoding Long-term Memories

• LTM
• Storage of info over time (gt30sec)
• Limitless capacity
• Encoding transforming new info into form for
  later retrieval
• Maintenance rehearsal
• Elaborative rehearsal
• focus on meaning, relate to existing info
• Ie. elaborate on new material in meaningful way
• Why is elaborative rehearsal more effective?

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Levels-of-processing Framework

• Craik Tulving, 1975
• The level at which new info processed determines
  how well it will be encoded remembered
• deep processing (meaning) more effective than
  shallow (repetition)
• Implications for studying?

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Subsystems of LTM

• Different types of amnesia in patients with
  different areas of brain damage
• Separate, but interacting subsystems
• Explicit memory
• Memory with awareness
• Declarative memories
• Implicit memory
• Memory without awareness
• Still affect behaviour etc.
• Non-declarative memories

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Types of Info in LTM

• Procedural
• Eg. skills, actions
• Easy to demonstrate, difficult to describe
• Episodic
• Specific events (inc. time place)
• Autobiographical memory
• Semantic
• General knowledge (facts, names, definitions,
  concepts, ideas)
• Usually dont remember when/where originally
  acquired info

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Activity 1 minute to study following words

• chair
• boat
• footstool
• orange
• pear
• peach
• bed
• bus
• train
• plum
• grapes
• motorcycle

• apple
• car
• airplane
• lamp
• banana
• dresser
• couch
• bookcase
• truck
• table
• strawberry
• bicycle

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Activity

• Count backwards by threes from 108 0
• Write down as many words from list as you can
  remember
• Clusters?

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Organisation of Info in LTM

• Clustering
• Organising items into related clusters
• Pieces of info in LTM are logically organised
  linked
• Semantic Network Model
• Concepts are linked in semantic network
• Some more strongly than others
• Activated concept can spread, activating other
  associations

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Retrieval

• Process of accessing stored info
• Retrieval cue clue, prompt
• helps trigger recall of stored memory
• Retrieval cue failure
• Inability to recall LTMs due to inadequate or
  missing retrieval cues
• Tip-of-the-tongue experience
• Often produce bits of related info or words with
  similar sounds or meanings
• Retrieval isnt all-or-nothing process
• Difference b/w stored info accessible info
• Many memories only appear to be forgotten

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Retrieval

• Free recall
• no retrieval cues
• Cued recall
• in response to retrieval cue
• Recognition
• identify correct info from several choices
• Serial position effect
• Primacy effect
• Recency effect

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Encoding Specificity Principle

• Context effect
• Environmental cues (external) can become encoded
  as part of memories can act as retrieval cues
• Remember info more easily when retrieval occurs
  in same setting as learning
• State-dependent retrieval
• Critical factor is effect of drug on persons
  internal state
• Better free recall when pharmacological states of
  learning retrieval match
• Effects very weak limited to free recall
• Mood Congruence
• Given mood influences types of memories recalled

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Flashbulb Memories

• Vivid, distinctive memories produced by
  significant events
• Recall of very specific images or details
• Easier to retrieve
• High degree of confidence in accuracy
• But, no more accurate than normal memories
• Remember some details, forget some think we
  remember others

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Forgetting

• Inability to recall info previously available
• Does have some adaptive value
• The Ebbinghouse Forgetting Curve
• Used nonsense syllables (WIB, MEP)
• Tested his recall 20min - 31 days

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Ebbinghouse Forgetting Curve

• Much of what we forget is lost relatively quickly
• Depends on encoding, processing depth, rehearsal
• Amount of forgetting levels off
• Info not quickly forgotten is fairly stable
• Basic pattern of forgetting
• Rapid forgetting of some info soon after original
  learning, followed by stability of remaining
  memories

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Factors That Influence Forgetting

• Encoding failures
• Info never encoded from STM to LTM
• Interference 1 memory competes with or replaces
  another
• More similarity more likely interference
• Retroactive new interferes with old
• Proactive old interferes with new

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Factors That Influence Forgetting

• Motivated forgetting usually unpleasant or
  disturbing memories
• Suppression deliberate, conscious effort
• Repression unconscious, all memory of
  event/experience blocked from conscious awareness
• Decay Forget memories not used
• New memory creates memory trace
• Memories fade over time due to normal brain
  processes

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Reading

• Hockenbury Hockenbury (2003)
• pp. 244-254
• pp. 260-265
• Next week
• Psychopathological, repressed, eyewitness
  accounts