interference theory

• This theory argues that we forget because similar memories interfere with (or disrupt the recall of the other) this can be seen as either an inability to recall at all, recalling the wrong piece of info or a mix of both pieces of info.
• Retroactive Interference = When a recent memory interferes with the recall of earlier info e.g. Not remembering your old password as you have recently changed in - new info interfering with old info
• Proactive Interference = when an earlier memory interferes with the recall of recent info e.g. Using an old password because you cant remember the new one - old info interfering with new info
• Underwood 1957

  Procedure = Analysed the findings from a number of studies and concluded that when ppts 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 on
• Underwood

  Findings = Ppts memorised 10 or more lists, then, after 24 hours they remembered about 20% of what they learned. If they only learned one list, recall was over 70%

  
  

  So.. proactive interference
• McGeoch and McDonald 1931

  Procedure = Gave ppts a list of 10 adjectives (List A) and asked to learn them, then given a resting interval of 10 minutes during which they learned List B followed by recall.
• McGeoch and McDonald 1931

  Findings

  • If List B was synonyms of List A, recall was poor (12% recall)
  • If List B was nonsense syllabus, this had less effect (26% recall)
  • If List B was numbers, this had the least effect (37% recall)
  • Shows that interference is strongest the more similar items are, only interference can explain such effects

  So... proactive interference
• Baddely and Hitch 1977

  Procedure = Investigated interference effects in an everyday setting of rugby players recalling the names of the teams they had played over the season, some players played in all the matches and some did not.
• Baddely and Hitch

  Findings = If the interference theory is correct, then those players who played the most games should forget proportionately more because of interference - which is what Baddeley and Hitch found

  So.., proactive interference
• Strengths of interference theory

  • Some research has high ecological validity e.g. Baddeley and Hitch, who found the same as lab research
  • Applications to advertising - Danaher et all (2008) = 2008 memory of an advert is poor if exposed to competitors adverts within the same week
• Limitation of interference theory

  • Most research takes place in lab settings with artificial tasks - lacking mundane realism
  • Interference doesn't account for all forgetting - two pieces of info need to be relatively similar, this is not the case in all pieces of info that we forget. Interference plays a role, but the extent of that role is unclear