Research on duration - Duration of STM

• Who conducted this research and when?

  Peterson and Peterson (1959)
• Procedure-


  - Tested 24 undergraduate students.

  - Each student was given a constant syllable (also known as a triagram) to remember and was also given a 3 digit number.

  - This student was then asked to count backwards from that 3 digit number until told to stop ( this counting backwards to prevent any maintenance rehearsal of the constant syllable.

  - On each trial they were told to stop after a different amonut of time: 3,6,9,12,15 or 18 seconds. This is called the retention interval
• Findings-

  Peterson & Peterson found that the longer the interval the less accurate the recall. At 3 seconds, around 80% of the trigrams were correctly recalled, whereas at 18 seconds only 10% were correctly recalled.
• Conclusion


  Suggest that STM duration may be about 18 seconds , unless repeat the information over and over again