explanations for forgetting

• interference occurs when new information interferes with previously learned material, either by disrupting encoding or recall.
• proactive interference 


  an older memory interfering with a newer one

  eg. old memories of driving on the left hand side of the road in the UK interfering with the new of driving on the right hand side in spain
• retroactive interference


  newer memories interfering with older ones

  eg. new memories of driving on the right hand side of the road in spain interfering with driving on the left hand side of the road when returning to the UK
• effects of similarity - mcgeoch and mcdonald 1931


  • studied retroactive interference by changing amount of similarity between 2 sets of materials.
  • Ps had to learn a list of words until they could remember them 100% accurately. they then learned a new list
  • group 1 (synonyms) had the lowest amount of recall, because they are similar to eachother so it creates a lot of interference
  • group 6 (no new list) had the highest amount of recall because there is no interference at all
• evidence from lab studies- interference theory

  • one of the most consistently demonstrated findings in whole of psychology
  • 1000s of lab experiments carried out, most show both types of interferences are likely to be the common ways we forget from LTM
  • scientific - replicable, observable and measureable
• artificial materials


  stimulus material is mostly words, more realistic than consonant syllables, but quite a distance from things we learn / try to remember in everyday life - eg. faces, names, ingredients in recipes
• rugby player study - baddeley and hitch 1977


  • asked rugby players to remember the names of the teams they had played so far that season
  • players who had played in more games had worse recall than those who had played less games over the same amount of time, therefore having higher interference
  • this shows time doesnt have an impact on forgetting, the number of similar events does
• retrieval failure 


  not being able to recall or remember a piece of information
• encoding specificity principle


  tulving states that - the greater the similarity between the encoding event and the retrieval event, the greater the chance of recalling the original memory

  so... forgetting happens when the 2 dont match
• context dependent forgetting


  based on external environment and cues

  godden and baddeleys 'diver training' study:

  • divers tested learning and recalling lists of words on land and underwater in different combinations
  • Ps performed better when they recalled the info in the same environment that they learnt it
  • recall was 40% worse when they didnt match as there was an absence of cues in the recall environment
• state dependent forgetting


  based on internal cues (of the body)

  carter and cassaday's antihistamine study :

  • Ps tested learning and recalling information on the drug and not on the drug in different combinations
  • it had a mild sedative effect
  • Ps performed significantly worse when the internal environments aren't the same for the learning and recalling
• strength - real world applications


  retreival cues can be used in order to overcome forgetting in everyday situations. eg. revising for tests in the same environment that you will be recalling the info in
• strength - helping dementia patients

  • memory boxes used to unlock autobiographical memories
  • boots recreated items from the past like perfume / cameras
  • 1950s village recreated for dementia patients - alternative since care homes are not hugely stimulating
• weakness 


  the supporting studies are not very strong because in everyday life our environments are not as different as those in the research
• weakness - diver study repeated

  • this time Ps were given a list of words and they would circle the ones they had learnt (cues)
  • everyone could do it no matter the situation
  • meaning the study is too simple
  • mismatch only effects recall not recognition
• interference and cues - tulving and psotka 1971


  • interference is temporary and can be overcome by using cues