Lesson 2 - Coding, Capacity and Duration

Question 1

Baddeley 1966 - Short Term Memory

Answer 1

Gave participants 4 lists of words to recall.
List A words sounded similar
List B words sounded dissimilar
List C words had similar meanings
List D words had dissimilar meanings
Recalled list B better than list A
No difference in recall for C and D
=> STM is coded acoustically (how it sounds, similar sounding words become muddled)

Question 2

Baddeley 1966 - Long Term Memory

Answer 2

Same procedure as STM study but 20 minute delay between recall ensuring information passed onto LTM
Recall of C was worse than D
No difference between A and B
LTM is coded semantically (organises information according to meaning, similar meanings become confused)

Question 3

Baddeley Evaluation (Positive +)

Answer 3

Laboratory experiment
Easy to replicate
Reliable

Question 4

Baddeley Evaluation (Negatives -)

Answer 4

Lack ecological validity

Lists of words is artificial as information recalled in everyday life is much different

Question 5

Jacobs 1887 - Capacity of Short Term Memory

Digit Span Test

Answer 5

Gave participants several sequences of digits or letters asking them to repeat after each sequence in correct order
Sequence increased in size by 1 each time
9.3 digits or 7.3 letters at once can be held in STM

Question 6

Miller 1956 - Capacity of Short Term Memory

Answer 6

Reviewed psychological research studies and concluded span of STM is 7 (+/-) 2
New information displaces the old information already stored
People can recall 5 words as easy as 5 letters
=> Chunking (grouping large amounts of information into smaller groups so more can be remembered)

Question 7

Evaluation of Short Term Memory (Positive +) - Jacob 1887

Answer 7

Research was first to acknowledge that STM capacity gradually improves with age

Question 8

Evaluation of Short Term Memory (Negative -) - Jacob 1887

Answer 8

Study was conducted a long time ago

=> Lower scientific standard as research today lowering validity of findings

Question 9

Peterson and Peterson 1959 - Duration of Short Term Memory

Answer 9

Used 3 random consonants to test STM duration
To prevent maintenance rehearsal, participants counted backwards from 100 in 3s
Recall after 3 seconds was 90%
After 9 seconds was 20%
After 18 seconds was 2%
Conclusion, information lasts in STM for 18-30 seconds without rehearsal before decaying

Question 10

Peterson and Peterson 1959 Evaluation (Positive +)

Answer 10

High level of control using standardised procedures to ensure all participants experience same process

• Fixed timings for participants to count backwards from
• Eliminated noise and other factors that could have an influence on memory

Question 11

Peterson and Peterson 1959 Evaluation (Negative -)

Answer 11

Findings of study may be caused due to interference rather than short duration of STM
=> Earlier trigrams became confused with later ones?

Question 12

Bahrick 1979 - Duration of Long Term Memory

Answer 12

Tested 400 participants of various ages (17-74) on memory of their classmates
Photo recognition consisted of 50 photos and deciding if they are classmates or not
Graduating class within 15 years 90%
48 years 70%
Recall of names within 15 years was 60% dropping to 30% after 48 years
Concluded duration of LTM is a lifetime but sometimes we have retrieval failure and need retrieval cues

Question 13

Bahrick et al 1979 Evaluation (Positive +)

Answer 13

Higher ecological validity than Peterson and Peterson 1959 as material was more meaningful and relevant to everyday life

Question 14

Bahrick et al Evaluation (Negative -)

Answer 14

Problematic to control extraneous variables such as stating in touch after leaving school and looking at yearbook