Study of capacity of STM
Miller (Immediate Digit Span Test)
Jacobs Support
Study of duration of STM
Peterson and Peterson (Trigrams)
24
... [Show More] students given a consonant syllable and a three digit number ie. THX 512.
They were asked to recall the consonant syllable after a retention interval of 3, 6 , 9, 12 or 15 seconds. During this interval they had to count backwards from their three digit number. Participants were 90% correct after 3 seconds, 20% correct after 9 and only 2% correct after 18 seconds.
Suggesting it is less than 18 seconds.
Study of duration of LTM
Bahrick (Free recall, photo recognition and name recognition tests)
400 people of various ages were tested on their memory of high school classmates.
They were given a free recall to recall as many class mates as they could. Then they were given 50 photos, some with people from their school year book. Bahrick found that recall after 15 years of graduation was 90% accurate from photos, and after 48 years was 70%. With free recall it was about 60% accurate and 30%.
Showing that it is possibly an unlimited duration for LTM.
Study of encoding
Baddeley (Semantically and Acoustically Similar/Dissimilar words)
Baddeley had lists of acoustically similar words such as: Cat, cab, can, map, mat, max etc.
And also semantically similar words: Huge, big, large, titanic, massive etc.
He found that participants had difficulty remembering acoustically similar words in the STM and in the LTM struggled with semantically similar words.
He concluded that STM is largely encoded acoustically whereas LTM is encoded semantically.
Capacity of STM
7+_ 2 units
Capacity of LTM
Potentially unlimited
Duration of STM
30 seconds
Duration of LTM
potentially unlimited
Encoding in STM
Mainly acoustically
Encoding in LTM
Mainly semantically
MSM of memory
Sensory Memory-> Attention->STM->(Maintenance rehearsal or) elaborative rehearsal->LTM->(Retrieval, Interference, Decay Retrieval failure, displacement for STM)
What does the MSM model suggest
It attempts to explain how memory works
Memory Consists of multiple stores
There is a sequence between these stores
Evidence to support the MSM
Glanzer and Cunnitz (primacy and recency effect)
HM (LTM gone)
Beardsley (Prefrontal cortex for STM and Hippocampus for Ltm)
(Bahrick Peterson and Peterson, miller, baddeley)
Evaluate the MSM
Too simple (but easier to understand)
Supporting Evidence
What does the WMM suggest
STM is made up of multiple stores and the MSM is too simple
What does the Central Executive do
directs attention to particular tasks and controls the 2 slave systems (phonological loop, visuo-spatial sketchpad)
What does the phonological loop do
processes and retains the order of heard information
can be divided into 2 substores
What can the phonological loop be divided into
phonological store (stores heard information, inner ear)
articulatory process (subvocal repetition, inner voice)
What does the visuo-spatial sketchpad do
plans spatial tasks and stores visual or spatial information
What can the visuo-spatial sketchpad be divided into
Visual cache (visual information)
Inner scribe (processes spatial relations)
What does the episodic buffer do
integrates information from all other STM stores [Show Less]