Forgetting

Forgetting

1. Incidental forgetting

   • Memory failures occurring w/o the intention to forget

2. Motivated forgetting

   • A broad term - normal forgetting and triggered by motivations but lacking conscious intention
     • Parker et al. (2008) The case of AJ > she remembers everyday of her life since teens

3. The relation between forgetting and time

   • Forgetting increases as time progresses
   • Ebbinghaus (1913) found a logarithmic relation between time and forgetting
     • The forgetting curve shows that info is losses very rapidly first and then levels off
   • Forgetting personal memories
     • Meeter et al. (2005) Widely publisiced events > recall dropped from 60 to 30% after a year (recognition only dropped to 52%)

4. The nature of forgetting

   • More is recognized than can be recalled (Tulving)
     • Availability > is the item in the memory store?
     • Accessibility > can the item be retrieved after being stored?

5. When do we forget?

   • When traces decay
     • A memory trace is a physical change in the brain
     • If traces are not used they will decay over time
     • What decays?
       • A memory's activation (underlying memory is left intact)
       • A memory's associations along with its activity levels
     • Devay in LTM often called "disuse" - use it or lose it
   • When there is interference
     • Hard to discriminate between similar memories - similar traces will increase over time
     • Interference = whenever the cue used to access a target becomes associated with other memories
     • Competition assumption (Anderson et al., 1994)
       • Interefrence increases with the number of competitors a target has
         • Ex. competition from noun meaning of 'duck' when asking for related verb 'crouch'
     • Cue-overload principle
       • Recall decreases with the number of to be remembered items that are paired with the same cue
     • Retroactive interference
       • Recently learned info effect retrieval of similar older memories
       • Barnes and Underwood (1959) Memory as a function of second-list learning
       • Baddeley and Hitch (1977) RI in everyday life
         • Rugby players > time did not increase forgetting, the number of intervening games did
     • Proactive interference
       • Older memories interfere with the retrieval of recent experiences/knowledge
       • PI effects are more severe when recall is tested rather than recognition
     • Retrieval induced forgetting
       • Retrieval can harm recall of other memories related to the retrieved item
       • Retrieval practice paradigm (Anderson et al., 1994)
         • Perform retrieval practice on 'orange' and not 'banana' for a drink category - 73% recalled orange, 38% recalled banana
       • RIF in the real world
         • In school
           • Reviewing facts
           • Answering MCQ and essays
         • Interrogation of witnesses
   • When retrieval induces forgetting

6. Why do we forget?

   • Blocking
     • Associative blocking
       • When a cue fails to elicit a target trace because it repeatedly elicits a stronger competitor, leading people to abandon efforts to retrieve the target
     • Unlearning
       • The associative bond linking a stimulus to a memory trace will be weakened when the trace is retrieved in error when a different trace is sought
   • Inhibition
     • A reduction in the activity level of a contextually inappropriate response
     • Properties of RIF
       • Cue independence
         • If 'banana' is inhibited it should be harder to retrieve even when generalized to unrelated cues (monkey-b___)
       • Retrieval specificity
         • Active retrieval from LTM is necessary to induce forgetting of 'banana' (fruit-or___)
       • Strength independence/ interference dependence
         • Blocking hypothesis predicts that any method of strengthening (retrieval or not) is sufficient