Interference Theory

• Interference


  Two pieces of information conflict with each other
• Proactive interference


  • Older memories disrupt newer ones
  • For example forgetting to drive on the right when you go on holiday abroad
  • Think: Proactive = Past (P) memories are interfering/prevailing
• Retroactive interference


  • Newer memories disrupt older ones
  • For example forgetting to drive on the left once you return from holiday
  • Think: retroactive = recent (r) memories are interfering/prevailing
• Effects of similarity

  • In both cases of retroactive and proactive interference, the interference is worse when the memories or learning is similar.
  • McGeoch and McDonald carried out a study where participants were split into 6 groups, where they all learned a list of words.
  • Each group then learned a new list, with varying degrees of similarity to the first.
  • When the participants were asked to recall the original list of words, the most similar list of words created the worst recall, which shows that interference is worst when the memories are similar.
• Strength: real-world interference

  • Baddeley and Hitch (1977) asked rugby players to recall the names of the teams they had played against during a rugby season.
  • The players all played for the same time interval (over one season) but the number of intervening games varied because some players missed matches due to injury.
  • Players who played the most games (most interference for memory) had the poorest recall.
  • This study shows that interference can operate in at least some real-world situations, increasing the ecological validity of the theory.
• Limitation: interference from cues

  • Interference is only temporary and can be overcome using cues.
  • Tulving gave participants progressively more lists of words organised into categories, leading to poorer recall as more lists were added due to proactive interference.
  • However, when participants were given cues of the categories recall rose back what it had been at the beginning.
  • This shows that interference only shows a temporary loss of accessibility to LTM, which was not previously realised.
• Proactive interference is the process where old information disrupts your ability to form new, similar memories.
• Retroactive interference is the process where new information disrupts your ability to remember old, similar memories.
• Strength: retrograde facilitation

  • The drug diazepam prevents new information from reaching the parts of the brain involved with processing memories.
  • A study found that people who learned the information before the drug had better recall than a placebo group.
  • On the other hand, learning information whilst on the drug led to poorer recall compared to a placebo group.
  • This finding shows that forgetting can be due to interference - reduce the interference and you reduce the forgetting.