Baddeley study

• Aim

  1966 aimed to find out if encoding for LTM was semantic or acoustic - tested for STM too
• Procedure

  Lab exp w independent groups design. 4 IVs. 75 Ps - young servicemen. Hearing test before and 3 excluded. 4 lists of 10. 4 separate groups listen to each. Presented aloud on tape. 1 word every 3 secs and 40 secs to write
• 4 lists

  A - acoustically similar

  B - acoustically dissimilar

  C - semantically similar

  D - semantically dissimilar

  Ps who recalled: A=18, B=17, C=20, D=20.
• unexpected task

  Ps spent 20 mins on unrelated task then asked to list again (not told about this before). LTM
• Findings

  On learning trials, recall of A lower than B and on recall test no sig forgetting of A but there was for B
• Finding ltm

  No sig dif of recall on C and D in learning trials and on recall test there was sig forgetting but equally for both
• Conclusion

  “Puzzling”. Performance on list A was only list to show no forgetting in LTM - suggests encoding is acoustic (contradicts earlier studies)
• Baddeley says

  Some aspecg of procedure was ‘hiding, semantic nature of encoding in LTM - so he did 2 more
• Strength 1

  High internal validity- well controlled as ABCD had equal frequency in English lang. Makes relation of IV and DV much clearer. Avoids confounding variables
• CA to strength 1

  Procedure didn’t rule out STM as an influence for later recall as Ps could still rehearse between trials
• Weakness 1

  Low external validity - too tightly controlled. STM and LTM prob do interact in real life like exp 1- but was seen as confounding variable to be eliminated. Only when Badelly increased control that semantic encoding was clear - so stufy exaggerates it’s role in real life
• strength 2

  application to learning to learn. Ltm being semantic can help improve long term recall of info - useful for students revising (mind maps). So meaning of material is processed not just repeated. Shows validity in terms of real life application.