Forgetting: Interference Theory

• What is forgetting?

  A person's inability to remember something that has been learnt.
• What was forgetting initially believed to be?

  A phenomenon called decay.
• What is the other suggested explanation for why people forget information?

  Interference
• What is Interference In Forgetting?

  When one memory disrupts the ability to recall a different memory.
• What are the 2 types of Interference?

  1. Proactive Interference
  2. Retroactive Interference
• What is Proactive Interference?

  Older memories interfere with the retrieval of newer memories.
• What is Retroactive Interference?

  New memories interferes with ability to recall previously held information
• How does Underwood show Proactive Interference?

  ln a meta-analysis where participants were asked to learn a list of words.

  - If participants had to memorise ten or more list after approximately 24 hours 20% was recalled.

  - If participants had to remember one list, after 24 hours they were approximately 70% accurate.

  • His conclusion was that PROACTIVE INTERFERENCE takes place when a person has to recall the most recent list.
  • This is due to interference from the previously learned lists
• What did McGeoch and McDonald find?

  Similarity of information increases interference
• What was McGeoch and McDonald procedure?

  Participants were given a list of ten adjectives [List A] and were asked to learn.

  - After this had been done they were giving a resting interval of ten minutes during this time they learnt [List B].

  • After it was followed by the recall of the two lists.

  It was found that [List B] was a list of synonyms of [List A] and recall was 21%.

  • If [List B] was nonsense syllables, recall was at 26%.
  • If [List B] was numbers instead of letters, recall was 37%.

  Proving that the greater the similarities between items the greater the extent of interference.
• Weaknesses of Interference Theory / Forgetting

  Some research evidence suggest some people are more susceptible to Proactive Interference than others.

  • Kane and Engle 2000 found that those with greater memory span were less susceptible to proactive interference.

  - This suggest that the original interference theory is overly simplistic and does not really account for individual differences
• Weaknesses of Forgetting/ Interference Theory

  Many psychologists believe that interference cannot account for all forgetting situations.

  - Research suggests that the 2 memories have to be similar for interference to happen and this is not common in every day life.

  • It can be argued that the interference theory is limited in helping in the understanding of forgetting in everyday life.

  ANDERSON 2000 concluded that;

  - Interference plays a role in forgetting but the extent of it is quite unclear.
• Weakness of Interference Theory?

  Research used to support interference theory uses artificial materials.

  - This means that it has low ecological validity as the material that were used in those researches do not apply to real life situations.

  • This further reduces the reliability of the findings and leads us to question of we the findings can actually be reliable on to support the theory.
• Strength of Lab Interference Theory

  Evidence from lab studies consistently demonstrated interference in our memory.