short and long term memory Flashcards
what’s capacity
how much can be stored in memory , such as number of digits
capacity of STM
assessed using digit span (443 female students had to repeat back a string of numbers or letters in the same order and the number of digits/letters was gradually increased, until the participants could no longer recall the sequence) JACOBS found that average span of was 9.3 items and 7.3 letters.
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MILLER believed that our short-term memory stores ‘chunks’ of information rather than individual numbers or letters eg phone number 07 456 04 9595 so we only need to remember 4 chunks of info.
MILLER FOUND people can people can recall 5 words and letters.
7+_3
a03 for capacity of StM
millers original study hasn’t been replicated. Cowan concluded that STM likely to be limited to about 4 chunks. suggests sym may not be as extensive
capacity of STM is not the same for everyone l, jacobs found digit span increased steadily in with age due to brain capacity, suggest stm is not fixed
what’s duration
how long memory lasts before it is no longer available/disappearing
the duration is STm
peterson and Peterson of 24 people. each trial participants given consonant (speech sound) syllable and 3 digit number (THX 282). they were asked to recall after intervals or 3,6,12,15 or 18 sec. during retention interval they had to count backwards from 3 digit number.
90% right over 3sec, 20% rughr after 9sec
STM HAS SHORT DURATION LESS THAN 18 SECONDS MAX 30 SECS
the duration of LTM
Babrick tested 400 people, recognition test consisted of 50 photos in high school yearbook. in recall test were asked to list all the names they remember.
participants 15 years within graduation were 90% accurate, after 48% declined to 70% dropped to 30% after 48 years.
a03 for duration of STM
was artificial, syllables doesnf reflect everyday activities. but we do try remembering meaningless things such as numbers, SUGGESTS although task was artificial, stify does have some relevance to life
a03 for duration of LTM
high levels of ecological validity as studies used real life memories, they used tral classmate photos
SUGGESTS reflects memory for rl events and can be applied to everyday life
what’s coding
how memory is stored
COding
acoustic ( sound) and semantic (meaning ) coding,
acoustically similar but semantically different: cat can cap
semantically similar but acoustically different : great large big huge
baddeley used word list to test affect of acoustic and semantic similarity on stm and ltm
FOUND that participants had difficulties remembering acoustically similar words in STM but not LTM. suggests stm is largely encoded acoustically whereas LTM is largely encoded semantically
a03 for coding
baddeley may not have tested ltm
it has been criticised that LTM was tested after waiting 20 minutes
