memory

paper 1

what are the assumptions of the multistore model

linear model

suggests that memory is made of 3 stores which are linked by processing

3 stores- sensory register, STM and LTM

each store has diff characteristics in coding, capacity and duration

how does the mutli store model work

info gathered from sensory organs is passes to sensory register

small amount of paid attention passes to STM, the rest of the info is lost quickly

info from STM which is processed through rehearsal gets transferred to LTM

what is the sensory register

recieves and stores info from the environment through our sense

if info in SR recieves attention it gets pased to the STM

if its not paid attention to, it decays and becomes forgotten

how is the sensory register coded

modality specific- info is stored in the form that it arrives

e.g. visual info enters iconic store and sound info enters echoic store

research- crowder- found that SR only holds info in iconic store for few milliseconds but for 2-3 secs in the echoic store- supports idea of sensory info being coded into diff stores

what is the capacity of the sensory register

capacity is quite large

research- sperling- flashed gird of letters on screen for 1/20th of a second, asked ppts to recall letters of one row

info faded quickly so he sounded different tones depending on the row which was called out (1/2/3)

recall of letters in indicated row high= info was already there- indicates capacity is large

duration of sensory register

limited= 0.5-3 secs

research- crowder (same as coding)

what is the function of short term memory

stores info which has been paid attention to in the SR

info must be rehearsed sucsessfully to be transfered to the LTM

how is STM coded

coded acoustically

encode info from SR by verballising it

e.g. saying out loud or repeating mentally

research- baddely- ppts split into 4 groups and shown diff lists of words depending on group (acoustically simillar/ dissimillar or semantically simillar/ dissimillar) ppts were asked to recall the words in a diff order

found that when recalling immediately after hearing ppts did worse with acoustically similar words- shows info is coded by sound

what is the capacity of short term memory

capacity is between 5 and 9 items

research- miller- didgit span test, ppts were read series of numbers and asked to recall them in the same order, amount of numbers increased each time untill ppts couldnt recall all numbers accurately

average didgit span was between 5 and 9 (7 plus/ minus 2)

what is the duration of short term memory

duration is 30 secs

research- peterson + peterson- ppts were shown a trigram and a 3 didgit number, then were asked to count down in sets of 3 from a number untill asked to stop, asked to stop at different times (3,6,9,12,15,18 secs)

found that 90% of trigrams were recalled correctly after 3 secs but only 5% correct after 18 secs

what is the function of long term memory

stores info for a very long time

how is long term memory coded

coding is semantic (meaning)

research- baddely (same study as coding for STM) memory for words with simillar meaning was poor after 20 mins

means info in LTM is coded semantically

what is the capacity of long term memory

capacity is unlimited

research- linton- kept diary of events on cards with a key word for each day

recalled events with 70% accuracy when given the keyword up to 7 years later

what is the duration of long term memory

duration lasts whole lifetime

research- bahrick- high school graduates were shown their classes yearbook photos and asked to match names with photographs

90% of ppts matched pics and names correctly 14 years after graduation and 60% 47 years after graduation

evaluation of the mulit store model

case study- clive wearing- contracted viral infection, left with brain damage, could still walk talk and play music but lost ability to form new LTM

supports MSM- supports idea of seperate stores for STM and LTM in MSM (couldnt transfer info from STM to LTM)

challenges MSM- couldnt leran new facts/ experiences, could learn new skills and still play piano- suggests how to do things stored somewhere else