Forgetting

• Name two explanations for forgetting

  1. Interference - either retroactive interference or proactive interference
  2. Retrieval failure
• What is retroactive interference?

  Retroactive interference (RI) = happens when a new memory interferes with an older one - this may be because the new learning disrupts the retrieval of the older memory associated with it

  —> e.g. you learnt to speak Spanish and this interferes with your ability to speak French
• What is proactive interference?

  Proactive interference (PI) = occurs when old memories interfere with newer ones - this may be because the original memory interferes with the formation/retrieval of new memories which are similar to it

  —> e.g. we get a new phone number, but keep recalling the old one
• Describe and explain the evidence for interference and the effect of similarity

  • McGeoch and McDonald (1931) studied the effect of similarity on retroactive interference
  • participants learnt a list of 10 words until they could recall with 100% accuracy, they then had to learn another list of 10 words (several different lists)
  • they were then tested again on the original list - those whose second list of words were synonyms to the first list did worst, those whose second list were 3 digit numbers did best

  —> this shows that retroactive interference is greatest with more similar memories
• Evaluate the strengths of evidence for interference and the effect of similarity (McGeoch and McDonald 1931)

  Strengths

  • evidence has been replicated many times, increasing its reliability and so giving us greater confidence in this explanation of forgetting - this is possible due to the use of highly controlled method use (laboratory experiment)
  • manipulation of the IV allows cause and effect relationships to be established and psychologists can be confident of the role of interference in forgetting under those conditions
• Evaluate the limitations of interference as an explanation for forgetting

  
  

  • using lists of words to investigate memory is more relevant to everyday life (greater ecological validity) than using nonsense syllables or lists of letters, but isn’t as realistic as using memory for e.g. names and faces - this artificiality means we cannot be sure that interference is as likely an explanation for forgetting in everyday life, as it is in the laboratory
  • the findings tell us little about interference when the memories involved are faces or episodic memories and other everyday life memories
• Evaluate a strength of interference as an explanation for forgetting

  • Real-world interference: Baddeley and Hitch asked rugby players to recall the teams they had played against that season - they found that recall for games played a few weeks ago was better if players had missed one or more games since then
  • this suggests that interference is the reason that the more regular players performed worse on recall - this demonstrates that interference can explain forgetting in real life situations, as well as in the more artificial laboratory environment - increases validity
• What is retrieval failure?

  where some information may be forgotten because we don’t have sufficient cues to enable us to retrieve the information we require from long term memory, even though the information is stored and therefore available
• What are cues?

  triggers that allow us to access information, often coded at the time of learning

  • may be internal cues e.g. mood, or external cues e.g. physical location
• What is encoding specificity principle?

  Encoding specificity principle suggests that cues must be present at the time of coding (learning) and also at time of retrieval if they are to help us recall information.

  • so we’re more likely to forget information if the same cues are not present when we try to recall as were present when we first learned something
  • examples: context dependent forgetting & state dependent forgetting
• What is context dependent forgetting?

  when we try (and fail) to recall information in a very different environment (context) to that in which it was learned

  • case study for context dependent forgetting = Godden and Baddeley - underwater vs. not underwater
• Explain the case study for context dependent forgetting

  • Godden and Baddeley asked divers to learn lists of words either on the beach or while underwater - half of each group were then tested on land, and half underwater
  • divers who learned and were tested in the same environment recalled 40% more words than those who tested in a different environment than the one in which they learned the words
  • this is because the external cues available at learning were different from the ones at recall which led to retrieval failure
• What is state dependent forgetting?

  when we try to recall information in a different internal state to the one we were in when we learned it

  • case study for state dependent forgetting = Carter and Cassaday - learning words with or without taking a mild sedative
• Explain the case study for state dependent forgetting

  • Carter and Cassaday used a design where participants were asked to learn words either with or without taking a mild sedative (anti-histamine) beforehand
  • those who learned and were tested in different states (drowsy and not drowsy) did significantly worse on recall than those who learned and were tested in the same state (both drowsy or both not drowsy)
  • so when internal cues that were there on learning are absent on recall, we’re more likely to forget
• Evaluate the strengths of Carter and Cassaday’s case study

  strengths:

  • highly controlled laboratory study --> easy to replicate
  • IV is manipulated by the researchers and the ability to randomly allocate to conditions should control for individual differences in memory between participants
  • good chance of establishing a cause and effect relationship, giving strong evidence that retrieval failure is a possible factor in forgetting
• Evaluate the limitations of Carter and Cassaday’s case study

  limitations:

  • task is artificial - learning word lists may not reflect forgetting in everyday life —> suggests that other factors may be involved in forgetting
  • artificial set up may’ve resulted in demand characteristics and some participants may have tried to fit in with the research aims —> further weakens the support this study gives to retrieval failure as an explanation for forgetting
• Evaluate the strengths of retrieval failure as an explanation for forgetting

  • two studies give good evidence that forgetting can be due to retrieval failure - it has been argued that this could be the main reason for forgetting in LTM
  • enduring success of the cognitive interview (recreating the context of the learning in order to help participants recall as much information as possible) strongly supports the importance of context dependent forgetting
• Evaluate the limitations of retrieval failure as an explanation for forgetting

  • it may be that the difference in context/state between learning and recall must be very great to lead to forgetting, and in real life such great differences may be rare so the research supporting it may lack external validity —> in real life, retrieval failure due to absence of cues doesn’t actually explain much forgetting
  • in everyday life, differences between learning and recall may be only subtly different —> explanation of forgetting may have only limited relevance to everyday learning