interference evaluation

• strength of mcgeoh and mcdonalds study is that they had high control over extraneous variables - able to control for distractions which could have caused further interference .

  • this is a strength because we can be sure it was the change in 2nd list which affects recall of list A
  • as a result internal validity is increased and this study provides support for retroactive interference.
• weakness of mcgeoh and mcdonalds study - use of artificial materials

  • example - they used a list of words to test the theory instead of realistic materials
  • this material does not reflect real life for example peoples birthdays. interference is much more likely in a lab as no emotions are attatched to the list of words
  • this means this study lacks ecological validity making interference less valid