Explanations for Forgetting

Explanations for Forgetting

1. Interference

   • Description of interference theory
     • Retroactive interference
       • New interferes with the old
       • Muller and Pilzecker (1990)
         • Gave participants a list of nonsense syllables to learn for 6 minutes, after a retention interval, asked to recall the list
         • performance was less good if participants had been given an intervening task between initial learning and recall
           • The intervening taks produced the RI because the later task interfered with what previously had been learned
     • Proactive interference
       • Old interferes with the new
       • Underwood (1957)
         • analysed the findings from a number of studies, concluded that when participants have to learn a series of word lists they do not learn the list of words encountered later on in the sequence as well as lists of words encountered earlier
         • Found that, if participants memorised 10 or more lists, then, after 24 hours, they remembered about 20% of what they learned,
           • if they had only learned one list the recall would be 70%
     • Similarity of test materials
       • McGeoch and McDonald (1931)
         • experimented with the effects of similarity of materials.
         • gave participants a list of 10 adjectives, then there was a resting interval of 10 minutes during whihc they learned List B, followed by recall
           • When list B was a list of synonyms of list A, recall was poor - 12% if list B was nonsense syllables this had less effect - 26%, if list B was numbers this had the least effect - 37%
             • This shows that interference is strongest the more similar the items are.
     • A real-world study
       • Baddeley and Hitch (1977)
         • investigated interference effects in an everyday setting of rugby players recalling the names of the teams they had played against over a rugby season.
         • Some players played all of the games, and some missed a few
         • If decay theory is correct
           • All players should recall a similar percentage of the games played, time alone should cause forgetting
         • If the interference theory is correct
           • players who played most games should forget more because of interference
   • Evaluation
     • Research is quite artificial
       • Words and nonsense syllables, and low motivation.
       • Doesn't represent everyday memory
     • Interference only explains some situations of forgetting
       • limited to some situations of forgetting, where two sets of stimuli are quite similar
     • Accessibility versus availability
       • Ceraso
         • Spontaneous recovery of recognition memory after interference suggests memories are avilable but not accessible
     • Real-world application to advertising
       • competing advertisements reduce their effect because of interference, better to show three in one day
     • Individual differences
       • People with greater working memory span less susceptible to proactive interference

2. Retrieval failure

   • Description of retrieval failure
     • The encoding specificity principle
       • Tulving and Thompson (1973)
         • Memory is most effective if information that was present at encoding is also present at retrieval
       • States that a cue doesn't have to be exactly right but the closer the cue is to the original item, the more useful it will be.
       • Tulving and Pearlstone (1966)
         • Demonstrated the value of retrieval cues in a study where participants had to learn 48 words belonging to 12 categories.
         • Each word was presented as category + word, e.g. fruit-apple, fruit-orange.
     • Context-dependent forgetting
     • State-dependent forgetting
   • Evaluation
     • There is a lot of research support
     • Real-world applications
     • Retrieval cues do not always work
     • The danger of circularity
     • Retrieval failure explains interference effects