Long And Short Term Memory

Question 1

What is the duration of the STM?

Answer 1

18-30 seconds

Question 2

What is the capacity of the STM?

Answer 2

7+-2 items

Question 3

Coding of the STM?

Answer 3

Acoustic

Question 4

What is the duration of the LTM?

Answer 4

Very long lasting

Question 5

What is the capacity of the LTM?

Answer 5

Potentially unlimited

Question 6

Coding in the LTM?

Answer 6

Semantic

Question 7

What was the aim of Peterson + Peterson’s 1959 study?

Answer 7

To investigate the duration of the STM

Question 8

What was the procedure of Peterson+ Peterson’s study?

Answer 8

24 students told a nonsense trigram
Then had to count backwards in 3’s or 4’s from a specific number for 3/6/9/12/18 seconds (prevent rehearsal)
Had to recall nonsense trigram

Question 9

What were the findings and conclusion of Peterson+ Peterson’s study?

Answer 9

After 3 seconds: 90% correct recall
After 18 seconds: 2%
STM lasts about 18 seconds when recall is prevented
Info lost from trace decay

Question 10

Aim of Shepherd’s 1967 study?

Answer 10

To investigate the duration of LTM

Question 11

Procedure/findings of Shepherd’s 1967 study?

Answer 11

Showed participants 612 memorable pictures one at a time
Showed them the pictures again one hour later amongst others and they showed almost perfect recognition
Four months later: still recognised 50% of photos

Question 12

Conclusion of Shepherd’s study?

Answer 12

LTM memories can be very long lasting

Question 13

Who discovered that chunking separate sections of information together increases the capacity of the STM?

Answer 13

Miller (1956)

Question 14

What was the procedure of Conrad’s 1964 study to investigate the type of coding in STM?

Answer 14

Showed students sequences of six consonants one at a time
Asked to recall sequences

Question 15

What were the findings and conclusion of Conrad’s study?

Answer 15

Similar sounding letters were harder to recall
Acoustically dissimilar letters were easier to recall
STM is mainly encoded acoustically

Question 16

What was the procedure of Baddeley’s 1966 study to assess if coding in STM and LTM is coded acoustically or semantically?

Answer 16

75 pps. presented with one of 4 word lists repeated 4 times
List A: acoustically similar words
B: acoustically dissimilar
C: semantically similar
D: semantically dissimilar
Given a list containing original words in wrong order (20 minutes later when testing for LTM, immediately for STM)
Had to rearrange into correct order

Question 17

What were the findings of Baddeley’s 1966 study?

Answer 17

STM: worst recall for list A (acoustically similar) (10% recall)
Acoustic confusion suggesting STM is coded acoustically

LTM: worst recall for list C (semantically similar) (55% recall)
Semantic confusion suggesting LTM is coded semantically

Question 18

Strengths/ weaknesses of lab memory studies

Answer 18

Strength: allows repetition, controlled environment, increases reliability, minimises extraneous variables
Weakness: lacks mundane realism,
low ecological validity (relevance of studies variables to real world context)

Question 19

Bahrick et al. 1975 yearbook study

Answer 19

Investigated duration of LTM
392 American uni graduates
Shown photos from high school yearbook and had to match names to faces
14 years later: 90% correct recall
47 years: 60% correct
Very long LTM duration