the multi store model

what does coding mean

the way information is manipulated so it can be stored in memory

Baddeley groups

• group 1 = acoustically similar words

• group 2 = acoustically dissimilar

• group 3 = semantically similar

• group 4 semantically dissimilar

Baddeley short term memory results

• when asked to recall straight away group 1 had the worst recall suggesting in the STM its encoded acoustically 

what does baddeley say the stm gets confused by 

it gets confused by acoustically similar words but can remember semantically similar words because it doesnt pay attention to what the mean and wont get it muddled up 

baddeley long term results

after 20 minutes group 3 had the worst recall suggesting that the LTM is coded semantically

what does the LTM get confused by 

semantically similar words 

Evaluation of coding

A = studies are completed in labs e.g. baddeleys and so he had control over extraneous variables , high internal validity

D = its not clear how long we need to wait to test the LTM so if baddeley waited longer would the results have changed

Sperling 1960 sensory register - procedure 

• P’s shown a grid of 12 letters 

• group 1 had to recall all 

• group 2 had to recall one row

Sperling 1960 sensory register - findings

• group 1 = 42% recalled 4/12

• group 2 = 75% recalled ¾

Sperling 1960 sensory register - conclusion

the sensory register has a very brief duration and the info fades before it can all be reported 

Jacobs 1887 - + for stm having limited capacity - procedure

• P’s were given a list of numbers to remember that got longer by 1 each time 

• the numbers were shown one at a time 

• digit span = number of numbers recalled correctly 

Jacobs 1887 - + for stm having limited capacity - findings 

• on average the STM could store 5-9 numbers 

Jacobs 1887 - + for stm having limited capacity - conclusion

STM has a limited capacity

Jacobs 1887 - + for stm having limited capacity - link

• millers magic number

• he said that chunking numbers means that we will be able to remember more

• e.g. we chunk phone numbers and so we can now remember 11 numbers instead of 5-9

Peterson + peterson 1959 = + for stm duration - procedure

• 24 student participants

• given 3 consonants (trigram) and told to count back in 3’s from a random 3 digit number out loud 

• asked to record the trigram after different time delays 

Peterson + peterson 1959 = + for stm duration - conclusion

when numbers/letters arent rehearsed recall levels are very low 

Peterson + peterson 1959 = + for stm duration - findings

• shows the duration of the STM is 18-30 seconds

• after 18 seconds only 10% recalled it correctly 

Bahrick = + for LTM - procedure

• 440 P’s ages 17-74 asked to remember their school classmates either free recall or from photos 

Bahrick = + for LTM - findings

• tested within 15 years and accuracy was 90% 

• tested after 48 years and accuracy was 70%

what are the strengths of Baddeleys study

• controlled lab setting

• standardised procedure means its replicable

what are the limitations of baddeleys research

• artificial task

• mundane realism

what are the strengths of Jacobs study

• controlled lab setting

• standardised procedure so it replicable

• role of age is acknowledged

what are the limitations of Jacobs study

• artificial task

• mundane realism

limitations of research into the capacity of the LTM

its often done using case studies so its not representative

what are the strengths of Bahrick

it uses meaningful memories as stimuli which means it has high external validity and can be generalised to real life

glanzer and cunitz procedure

• they gave participants a list of words and were asked to recall them straight away

glanzer and cunitz findings

• there was good recall for the 1st part of the list = primacy effect

• there was good recall for the end of the list = recency effect

glanzer and cunitz conclusion

the STM and LTM are separate stores

what is a criticism of the STM

the case study of KF

• he was in a motorcycle accident had brain damage

• could remember things he saw but not what he heard

• shows the STM has more than one store