Interference

• interference theory

  Forgetting occurs when one memory disrupts or blocks another, causing one or both memories to become distorted, lost or inaccessible
• Retroactive interference

  New disrupts old (<-)
• Proactive interference

  Old disrupts new (->)
• The more similar the information, the greater the likelihood of interference occurring (response competition)
• Underwood (1957)


  Participants are given lists, tested, then given another list

  The percentage accuracy dropped per lists

  Demonstrates that the more lists a participant has to learn, the harder it becomes

  Supports proactive interference
• Underwood 1957

  Lacks ecological validity / mundane realism

  Controlled environment
• McGeoch and McDonald 1931

  Participants learnt a list of 10 words off by heart

  Then split into 6 groups to learn 6 more words

  participants asked to recall

  The more similar the second list to the first list - the worse the performance

  Supports retroactive interference
• McGeoch and McDonald 1931

  Lacks ecological validity / mundane realism Controlled environment
• Schmidt et al (2000)

  700 former students at a Dutch school were randomly selected (aged 11-79)

  Asked to recall local street names around their school

  The number of times they’d moved house while at school was recorded to

  the results support the idea of retroactive interference, as the learning of new information (new street names) seems to have interfered with memory of old information (OG street names)
• Real life forgetting example

  Rugby players recall of the team they last played dependant on how long ago they matched them