Duration of Memory stores

Peterson and Peterson 1959- STM 

24 participants were tested over 8 trails, on each trail they were given a consonent syllable and a 3 digit number. they were asked to recall the consonant syllable after a retention interval of 3,6,9,12 or 18 seconds during which they had to count backwards from their given 3 digit number. 

after 3 seconds- 90% correct

after 9 seconds - 20% correct 

after 18 seconds- 2% correct 

suggest that the stm duration is less than 18 seconds.

Bahrick et al 1975- LTM 

tested 400 people (17-74yo) on the memory of their class mates. 

Photo recognition condition consisted…