(2) memory Flashcards
what are the two memory stores and how are they distinguished?
• STM and LTM
• coding, capacity and duration
what is the meaning of coding in memory stores?
the format in which info is stored, info can be encoded visually, semantically or acoustically
who studied coding in STM and LTM and in what year?
Baddeley, 1966
how did baddeley conduct his experiment?
provided different lists of words to 4 groups of Ps and asked them to recall the words in the correct order immediately or after a 20 minute interval.
group 1 recieved acoustically similar words
group 2 - acoustically dissimilar words, group 3 - semantically similar words, group 4 - semantically dissimilar words.
how did Ps perform in STM tests (immediate recall)?
did worse with acoustically similar words during immediate recall
how did Ps perform in LTM tests (after 20 minute interval)?
did worse with semantically similar words after a 20 minute interval.
what do these findings indicate about memory encoding?
STM encodes acoustically, while LTM encodes semantically.
what is the meaning of capacity in terms of memory?
maximum amount of info that can be held in a memory store.
what is believed about the capacity of STM, as supported by ____ and ____ , and LTM capacity?
include years
• capacity of STM is limited, while capacity of LTM is theorised to be unlimited.
• Jacob’s (1887) and Miller (1956)
how did Jacob’s (**) investigate the capacity of STM?
• 1887
measured Ps digit span by having them recall a list of digits in the correct order, increasing the sequence length by one digit until they answered incorrectly.
what were the findings of Jacobs’ study?
the mean span among all Ps was 9.3 for digits and 7.3 for letters, indicating a limited capacity of STM (around 7-9 items).
how did Miller (**) investigate the capacity of STM?
*1956
observed everyday practices and noted that things often come in groups of sevens, (7 deadly sins, 7 days in a week, 7 notes in music)
what conclusion did miller draw from his observations?
capacity of STM is around 7 plus/minus 2 items, depending on how individuals ‘chunk’ information together
what is duration in terms of memory?
how long information can be held in memory.
who investigated the duration of STM and LTM and in what years?
STM - Peterson and Peterson (1959)
LTM - Bahrick et al (1975)
how did peterson and peterson (**) investigate the duration of STM and what did they find?
• 1959
Ps presented with trigrams and then retention intervals (ranged from 3-18 seconds where Ps counted backwards from 3) to test recall, finding that without rehearsal, STM duration is about 18-30 seconds.
how did Bahrick et al (**) investigate the duration of long-term memory
• 1975
tested recall of school yearbook info from 15, 30 and 48 years after graduation, using photo recognition and free recall tests.
what were the results of Bahrick et al’s (——) study?
• 1975
photo recognition remained high even after 48 years, but free recall accuracy declined over time, suggesting some LTM info may last a lifetime.
a03 coding
✅ - demonstrated difference between STM and LTM
evidence: (1996) word recall study showed STM codes information acoustically, LTM codes information semantically
explain: strengthened understanding of distinct memory story’s; contributed to development of Atkinson & Shiffrin’s MSM principles (1968)
a03 coding
⭕️❌- methodological limitations to Baddeleys (——) study
🦄 - study was highly controlled, therefore reliable results
❌
point:(1996)
evidence: used artificial stimuli in controlled lab setting as word lists lacked personal meaning for Ps
explain: low ecological validity due to tasks lacking mundane realism, impacting real-world applicability
a03 capacity
⭕️✅ - Jacob’s research (——) is well-replicated in more recent studies
🦄 - Jacob’s original study had methodological limitations
point: 1887
evidence: better controlled 2005 meta-analysis taken place, built upon understanding
explain: supports validity of Jacob’s digit span test for STM capacity (so likely to be 5-9 items)
a03 capacity
⭕️❌ - Miller’s findings may have been overestimated
🦄 - Miller’s findings still hold value
❌
point:
evidence: Cowan’s (2001) study suggests capacity closer to 3-5 chunks
explanation: Miller’s observations might have led to an inaccurate estimate
a03 duration
⭕️❌ - methodological limitations to Peterson and Peterson (——) study
point: (1959)
evidence: used artificial stimuli in controlled lab setting as trigrams lacked personal meaning for Ps
explain: low ecological validity due to tasks lacking mundane realism, impacting real-world applicability
who created the MSM and in what year?
Atkinson and Shiffrin (1971)
what is the MSM?
a theoretical analogy likening memory processing to computer info processing
• flow of info through three passive memory stores in a fixed, linear sequence
• potential loss via displacement or decay
what are the three passive stores of the MSM?
sensory register, STM, and LTM
what is the role of the sensory register in MSM?
initial store, where sensory info is detected and either quickly discarded or transferred to STM through attention
how is the sensory register in the MSM coding?
modality specific manner (eg. visual as iconic memory)
what is the capacity of the sensory register in the MSM?
large, all sensory experience from day to day life is absorbed
what is the duration of the sensory register in the MSM?
brief, less than 0.5 seconds
how is STM coded in the MSM?
(include studies)
acoustically, evidenced by poorer recall for acoustically similar words in Baddley’s study (1966)
what is the capacity of STM in the MSM?
(include studies)
7 plus or minus 2 items, as evidenced by Jacob’s digit span study (1887) and Miller’s observations on everyday practices (1956).
what is the duration of STM in the MSM?
(include studies)
limited to 18-30 seconds, as evidenced by Peterson and Peterson’s (1959) study of tasking Ps to memorise trigrams and including retention intervals that ranged from 3-18 seconds
what role does STM play in the MSM?
second store; through attention, info is passed here and passes into LTM through maintenance rehearsal
what role does LTM play in the MSM?
final store that acts as brains hard drive, info is stored through maintenance reahearsal and can be passed to STM through retrieval