short term memory Flashcards
who investigated Coding in short term memory?
Baddeley
what was the procedure of Baddeley’s study?
he gave different lists of words to 4 groups of ps to remember. Group 1 was acoustically similar, group 2 was acoustically dissimilar, group 3 was semantically similar, group was semantically dissimilar
what was the result of Baddeley’s study?
when they did this task immediately recalling from their STM they tended to do worse with acoustically similar words. When they did this task 20mins later recalling from their LTM they did worse with semantically similar words
what was the conclusion of Baddeley’s study?
information is coded acoustically in STM and semantically in LTM
who investigated capacity of memory?
Joseph Jacobs
what was the procedure of Jacobs’ study?
the researcher reads out 4 digits, and the participant recalls these in the right order. If they’re correct then the researcher will read out 5 digits, and so on until the ps can’t recall anymore
what was the findings of Jacobs’ study?
the mean span for digits across all ps was 7+- 3
who else investigated research on capacity?
Miller made observations of everyday practice. e.g he notes that most things come in 7s
what were Miller’s findings?
the span of STM was 7+-2
what is chunking?
grouping digits or letters together to make them easier to remember. Most people can recall 5 words as easily as they can recall 5 letters by chunking
who investigated the duration of STM?
Peterson & Peterson
what was the procedure of Peterson & Peterson’s study?
tested 24 students in 8 trials each. The student was given a trigram to remember and told to count back from a 3 digit number until told to stop. On each trial they were told to stop after varying times (3,6,9 etc)
what was the result of Peterson & Peterson’s study?
after 3 secs, average recall was about 80%. After 18 secs it was 3%
what was the conclusion of Peterson & Peterson’s study?
STM duration may be about 18secs unless we repeat the information over and over again
who investigated the duration of LTM?
Bahrick
what was the procedure of Bahrick’s study?
he studied 392 american participants between the ages of 17 and 74z He tested their recall with their high school year books. He did 1 photo recognition test, and 1 free recall test
what was the result of Bahrick’s study?
ps tested with 15 years of graduation were 90% accurate in photo recognition. This declined to 70% after 48 years. ps tested after 15 years for the free recall were 60% accurate. This declined to 30% after 48 years.
what was the conclusion of Bahrick’s study?
LTM may last a lifetime for some material
Who idesntified different memory stores?
Baddeley
why does Baddeley’s study have a lack of environmental validity?
He used an artificial stimuli as none of the words had any personal meaning to the ps. When processing more meaningful information, people may use semantic coding even for STM tasks
why is Jacob’s study valid?
his study has been repeated despite how old it is. His findings have been confirmed by other better controlled studies
what is a limitation of Miller’s study?
he may’ve overestimated the capacity of STM as Cowan reviews other research and concluded that the capacity of STM is only 4+-1 chunk
what is a limitation of Peterson & Peterson’s study?
the stimulus material was artificial. It isn’t completely irrelevant as we do sometimes try to remember meaningless information but recalling trigrams doesn’t reflect everyday memory activities. The study lacks external validity
why does Bahrick’s study have high external validity?
The researchers investigated meaningful memories to the ps. When studies on LTM were investigated with meaningless pictures, recall rates were lower. Bahrick et al’s findings regel et a more real estimate of the duration of LTM
