coding, capacity, duration STM Flashcards
How many groups were there in Baddeley (1966)’s study?
4
What was the procedure of Baddeley (1966)’s study?
-4 groups
-given different word lists to remember
-Group 1: acoustically similar
-Group 2: acoustically dissimilar
-Group 3: semantically similar
-Group 4: semantically dissimilar
-The groups were then asked to recall the words from the list in the correct order immediately after
How can duration of STM be increased?
Maintenance rehearsal
What was the procedure of Peterson and Peterson (1959)’s study?
-24 students tested in 8 trials
-On each trial, the participant was given a consonant syllable (e.g CYH) and 3 digit number to remember
-the student counted backwards from this number until asked to stop (after varying periods of time) to prevent mental rehearsal of the consonant syllable
How did Miller propose STM capacity be increased?
chunking
What was the procedure of Miller’s study?
-Miller observed everyday practice
-He observed that things come in sevens such as the days of the week and the deadly sins.
What were the findings from Baddeley (1966)’s study? What did this suggest about STM
On average, they did worse with the acoustically similar words
-that information is coded acoustically in STM.
Who studied duration of STM?
Peterson & Peterson (1959)
What did Miller conclude from his study?
-the span of STM was about 7 items plus or minus 2
-people can recall 5 words as easily as they can recall 5 letters through chunking
How long did Baddeley (1966) wait before asking the group to recall the word list? Why?
-Immediately After
-So that they would be recalling from their STM
Weaknesses?
-Peterson and Peterson’s (1959) study had artificial stimulus material
What is chunking?
grouping sets of digits or letters into units/chunks
What were the findings of Peterson and Peterson’s study?
-On average, after 3 seconds, recall was approx. 80%
-On average, after 18 seconds, recall was approx. 3%
Strengths of STM coding capacity duration?
-Jacobs’ study has been replicated
-Baddeley’s study identified a clear difference between two memory stores
What is the duration of STM?
18 seconds
Explain the strength that Jacobs’ study has been replicated?
-Early research and studies often lacked adequate controls.
- there may have been a confounding variable such as participants being distracted during testing, meaning that their digit spans might have been underestimated. -However, Jacobs’ findings have been supported/confirmed by other modern and more controlled studies suggesting that Jacobs’ study is a valid test of digit span in STM.
Who studied capacity in STM?
Jacobs (1887) and Miller (1965)
What study found how information is coded in STM?
Baddeley (1966)
What did Jacobs (1887) study? What was the procedure?
-Investigated ‘digit span’
-Researcher read out 4 digits and the participant recalled them back in the correct order. If they were correct the researcher read out 5 digits, and so on until the participant couldn’t correctly recall.
What is the capacity of STM?
7 +or- 2
Explain the strength that Baddeley’s study identified a clear difference between two memory stores?
-Later research showed that there are some exceptions to Baddeley’s findings
-but the idea that STM uses mainly acoustic coding and the long term memory store uses mainly semantic is still important today.
-This was an important step in our understanding of the memory system, which led to the multi-store model of memory.
What was the mean span for letters in Jacobs’ study?
-the mean span for letters was 7.3
Explain the limitation that Peterson and Peterson’s (1959) study used artificial stimulus material?
-study still has relevance because humans do sometimes try remember somewhat meaningless things (such as phone numbers)
-However, recalling consonant syllables does not reflect most everyday memory activities where we are trying to remember meaningful things.
-This means the study lacked external validity due to lack of generalisability.
What was the mean digit span in Jacobs’ study?
-the mean digit span across all participants was 9.3
How is information coded in STM?
Acoustically
What did Peterson and Peterson conclude from their study?
-that STM duration may be about 18 seconds, unless there is mental rehearsal
What were Jacobs (1887)’s fimdings?
-the mean digit span across all participants was 9.3
-the mean span for letters was 7.3
