Baddeley's study

• Aim: to investigate whether LTM and STM have the same acoustic encoding system.
• o   72 participants given 4 lists of 10 words (semantically similar/dissimilar and acoustically similar/dissimilar) all recruited from applied psych research unit.

  o   Each list was presented via slideshow at 1 word/3 seconds in the correct order which was the same for every participant.
• o   Given interference tasks where they had to remember digits. This was to block the effect of STM and make sure all learning in all the trials relied only on LTM.

  o   Then asked to recall the words by writing them down in the correct order in one minute.

  o   Baddeley wanted to see how many words could be recalled in the CORRECT ORDER.

  o   Then another 15-minute interference task followed by a surprise test
• Findings: People found the semantically similar words more difficult to learn than the semantically dissimilar words and recalled significantly fewer semantically similar words in the retest. Suggesting that LTM relies on semantic encoding.
• strength is the study was scientific it was conducted in a controlled lab environment with standardised procedure. Each word was shown for 3 sec for every participant, the same list of words, same order, same interference tasks for each group. This is a strength as it can be replicated to the see effects of acoustic and semantically similar words on STM and LTM. As it is highly controlled, the study can also be done with different interference tasks to show how memory can become susceptible to transformation. This also allows a cause-and-effect relationship to be established.
• Another weakness is that the study took place in a laboratory where individual words were read out/ shown to the participants which is controlled, this artificial situation lacks ecological validity because the participants may have changed their behaviour from real life and could have tried harder to learn the words unlike their daily use of memory.