Duration

• Artificial 


  Memorising consonents/syllables does not reflect everyday life

  Therefore not meaningful

  Low mundane realism, low ecological validity cannot generalise to everyday life

  However sometimes remember meaningless things eg postcode/phone number
• STM results due to displacement


  Counting numbers backwards may have displaced consonants/syllables

  Research used auditory tones instead of numbers so displacement would not occur

  STM was longer at 96 secs rather than Petersons 18 secs