Research

• Bahrick investigated duration of LTM
• Baddeley investigated coding in STM/LTM
• Miller investigated capacity of STM
• Glanzer and Cunitz investigated the distinct stores within memory
• Peterson & Peterson investigated duration of STM
• Baddeley - encoding in STM and LTM.

  75 pp's were allocated to one of 4 lists.

  1-acoustically similar

  2- acoustically dissimilar

  3- semantically similar

  4- semantically dissimilar

  • to test STM they were given a list of the same words in a different order and were asked to arrange them in the original order.
  • to test LTM they had to perform the same task after 20 mins to prevent rehearsal
  • Participants got more mixed up with similar sounding/meaning words.
• Miller - capacity of STM

  carried a literature review on published investigations on perception and STM from 1930-50

  • found that the STM has a capacity of 7+/-2 items
  • chunking helps us rmbr more
• Bahrick- duration of LTM

  400 participants aged 17-74 were asked to identify names and faces of classmates from a year book.

  • ppl who left in the last 15 years remembered 90%
  • ppl who left 40 years ago remembered 70%
  • LTM memories can last a lifetime
• Glanzer and Cunitz- investigated the distinct stores within memories

  Participants learnt a list of words varying in length from 10-40 words.

  • ppl remembered first (primacy effect) and last words (recency effect) more than the middle words due to serial positioning.
  • STM and LTM are distinct and unitary
• Peterson and Peterson- investigated duration of STM

  participants were asked to learn trigrams and were then told to count backwards from a 3 digit number, they were told to stop at different times.

  • after 3 seconds participants remembered 80% of trigrams
  • after 18 seconds participants recalled 10% of trigrams
  • duration of STM is 18-30 seconds and recall decreases over time