Memory: coding, capactiy and duration Flashcards
what’s the STM?
coding is acoustic, capacity is 5-9 chunks and duration is 18-30 seconds.
what’s LTM?
coding is semantically, unlimited capacity and duration is a lifetime
what’s research into coding?
Baddeley gave different lists of words to 4 groups: acoustically/semantically similar/different. participants were asked to recall them in the correct order immediately after hearing them and 20 minutes after. in STM, they did worse in acoustically similar words and in LTM, they did worse on semantically similar words.
what’s research into capactity? (digit span)
Jacobs gave participants 4 digits that they were asked to recall. if this was correct, they were given 5 digits to recall and so on until they couldn’t complete it. he found the mean digit span was 7.3 and mean letter span was 9.3
what’s research into capacity? (span of memory and chunking)
Miller observed everyday practise and noted that things came in 7 - weeks, sins. he also noted that people could recall 5 words as well as 5 letters by chunking
what’s research into STM duration?
Peterson + Peterson tested 24 students. it was 8 trials long. they were given a consonant syllable (trigram) to remember and had to counted backwards from a 3 digit number to prevent rehersal. on each trial, they stopped after different amounts of time (3, 6, 9). it was found after 18 seconds, most people couldn’t do it.
what’s research into LTM duration?
Bahrick studied 392 participants from Ohio aged 17-74. they used highschool yearbooks to test photo-recognition and free recall. participants (15 yrs) had 90% accuracy for photo recognition and 60% for recall. after 48 years photo-recogntion was 70% and free recall was 30%
what’s limitation of Baddeley’s study? (A03)
it uses artificial stimuli rather than meaningful material. the word list has no personal meaning to participants. the findings can’t be generalised so have limited application.
what’s a limitation of Jacobs’s study? (A03)
it’s lacking validity as it was conducted a long time ago. early research often lacks control. participants may be distracted while being tested. this mean the results aren’t valid because of confounding variables that weren’t controlled.
what’s a strength of Bahrick’s study? (A03)
it has high external validity. real-life meaningful memories were studied. when studies on LTM used meaningless pictures, recall rates dropped. the downside is confounding variables aren’t controlled such as Bahrick’s participants may look at their yearbooks regularly.
