Interference

• Interference theory


  Proposed that forgetting occurs when 2 pieces of information are in conflict with each other.

  One memory blocks another causing one or more memories to become distorted.

  
  

  Information that has reached the LTM memory store is considered to be permanent, but interference can result in us having trouble locating that memory - which can be experienced as forgetting.
• Retroactive interference


  Forgetting occurs when newer memories disrupt the recall of older memories.

  
  

  Forgetting will be greater when the memories are similar.
• Proactive interference


  Forgetting occurs when older memories disrupt the recall of newer memories.

  
  

  Forgetting will be greater when memories are similar
• Competitive interference


  Proactive and retroactive interference are thought to be more likely to occur when the memories are similar.

  
  

  For example, students who study similar subjects at the same time often experience interference. French and Spanish are similar types of material which makes interference more likely.
• Underwood


  Meta-analysis of studies

  
  

  Pp's who learned 10 word lists or more = 20% recall

  Pp's who learned 1 word list = 70% recall

  
  

  Earlier lists hindered recall of later lists.
• Burke and Skrull (1988) - Procedure


  They presented a series of magazine adverts to participants. Participants had to recall the details (eg: brand names) from the advert they had seen.
• Burke and Skrull (1998) - Findings

  Participants experienced 2 different difficulties in remembering.

  
  

  In some cases, participants struggled to remember earlier adverts (retroactive interference). In other cases, participants had problems remembering the late adverts that were shown (proactive interference).

  
  

  This effect was greater when the adverts were similar - i.e. adverts were for identical products but different brands (competitive interference)
• A03 - Limitation (P)

  A limitation of the interference explanation of forgetting is presented by Tulving and Pstoka, who showed how the presence of cues can overcome the effects of interference.
• A03 - Limitation (E)

  Participants in their study were given 5 lists of 24 words to learn. Each word, on each list, could be placed in one of 6 categories (which weren't explicitly stated but where assumed to be obvious).
• A03 - Limitation (E)

  Recall was about 70% for the first word list, but this fell as participants were given an additional list to learn.

  
  

  However, at the end they were given a cued recall test. They were told the names of the categories as a clue. Recall rose again to about 70%.
• A03 - Limitation (L)


  This suggests that information hadn't suffered from interference, rather it was available in the LTM but not accessible.

  
  

  The information was present in the LTM but couldn't be retrieved without the aid of a cue (the category)

  
  

  In real life, this can be applied to the use of cues when revising to enable individuals to access memories of topics/concepts, and overcome the effects of interference.
• A03 - Strength (P)

  A strength is presented through real life research by Baddeley and Hitch, who tested the interference theory in an every day setting to determine if it was a better explanation of forgetting than the passage of time.
• A03 - Strength (E)

  The sample was comprised of rugby union players who'd played every match in the season, and players who'd missed some games due to injury.

  
  

  The length of time from the start to the end of the season was the same for all players.

  
  

  The players were asked to recall the names of the teams they'd played against earlier in the season.
• A03 - Strength (E)

  Results showed that accurate recall didn't depend on how long ago the matches took place. But what was more important was the number of games they'd played in the meantime.

  
  

  The players who'd played the most games forgot proportionally more games than those who'd played fewer games due to injury.
• A03 - Strength (L)

  Baddeley and Hitch concluded this was the result of retroactive interference, as the learning of new info (new team names) interfered with the memory of old info (earlier team names)

  
  

  This shows that the interference explanation has applications to everyday situations, thus increasing the ecological validity of the explanation.