what is the definition of coding?
the format in which information is stored in the various memory stores
what is the definition of capacity?
the amount of information that can be held in a memory store
what is the definition of duration?
the length of time information can be held in memory
what is the capacity, duration and coding of the STM?
- limited capacity: 5 to 9 items on average
- duration: 18-30 seconds
- coding is mainly acoustic
what is the capacity, duration and coding of the LTM?
- unlimited capacity
- duration: 2 mins - 100 years
- coding is mainly semantic
who conducted the digit span experiment, and what were the results?
- jacobs (1887)
- the average span = 9.3 digits and 7.3 letters
what did miller (1956) note about the STM capacity?
that it was actually 7±2 “chunks”
how did peterson and peterson (1959) test STM duration? what were the results?
- each ppt was given a consonant syllable and a 3-digit number and then asked to count from their number for 3, 6, 9, 12, 15, and 18 seconds
- 3 seconds = 90% recall; 9 seconds = 20%; 18 seconds = 2%
how did bahrick et al. (1975) test LTM duration? what were the results?
- used yearbook pictures as a cue in a photo recognition test and a free recall test
- photo = within 15 years: 90% accurate; after 48 years: 70%
- free recall = 60%, 30%
what were the strengths and weaknesses of jacobs’ (1887) experiment?
- results have been confirmed in other research, confirming their validity
- very long time ago; lacked adequate control; didn’t consider displacement/decay
what were the strengths and weaknesses of petersons’ (1959) experiment?
- not totally irrelevant (phone numbers); good distractor
- lacked general validity; didn’t consider displacement/decay
what were the strengths and weaknesses of bahrick’s (1975) experiment?
- high external validity (high recall)
- confounding variables not controlled
who used word lists to test the effects of acoustic and semantic similarity on STM and LTM, and when?
alan baddeley, (1966a and 1966b)
what were baddeley’s findings?
ppts had difficulty remember acoustically similar words in STM but not LTM
what are the strengths and weaknesses of baddeley’s (1966) experiment?
- only waited 20 mins to test LTM
- it used artificial stimuli (word lists rather than meaningful material)
