Coding, Capacity, Duration

Question 1

When was Baddeley’s Coding study?

Answer 1

1966

Question 2

When was Jacob’s Capacity study?

Answer 2

1887

Question 3

When was Miller’s Capacity study?

Answer 3

1956

Question 4

When was Peterson & Peterson’s Duration study?

Answer 4

1959

Question 5

When was Bahrick et al.’s Duration study?

Answer 5

1975

Question 6

What was the procedure of Baddeley’s 1966 study?

Answer 6

Tested the recall of Acoustically similar or dissimilar, and Semantically similar or dissimilar word lists.

Question 7

What did Baddeley’s 1966 study find?

Answer 7

Immediate recall was worse with acoustically similar words; STM is encoded acoustically. Recall after 20 mins was worse with semantically similar words; LTM is encoded semantically.

Question 8

What was the procedure of Jacob’s 1887 study?

Answer 8

Digit Span testing. The researcher read out an increasing number of digits until the participant cannot recall the correct order.

Question 9

What did Jacob’s 1887 study find?

Answer 9

Participants could repeat back an average of 9.3 numbers, and 7.3 letters. (this inspired Miller’s study)

Question 10

What was the procedure of Miller’s 1956 study?

Answer 10

Miller observed everyday practice and noted that many things come in groups of 7.

Question 11

What did Miller’s 1956 study find?

Answer 11

The span of STM is about 7 items +/- 2, but can be increased by chunking information into meaningful units.

Question 12

What was the procedure of Peterson & Peterson’s 1959 study?

Answer 12

24 students given 3 letter trigrams to recall. They counted backwards from a large number during the retention intervals in order to prevent rehearsal. The retention intervals varied: 3,6,9,12,15, or 18 seconds.

Question 13

What did Peterson & Peterson’s 1959 study find?

Answer 13

After 18 seconds, the average recall was 3%. STM duration without rehearsal is around 18 seconds.

Question 14

What was the procedure of Bahrick et al.’s 1975 study?

Answer 14

Tested 392 American graduates aged between 17 and 74. 1. Recognition test on photos from high school yearbook. 2. Free recall test listing names from their graduating class.

Question 15

What did Bahrick et al.’s 1975 study find?

Answer 15

After 48 years, the recognition test was 70% accurate, and free recall test 30% accurate. Shows that the LTM can potentially have an unlimited duration.

Question 16

Strength of Baddeley’s 1966 study

Answer 16

It identified two memory stores- this led to the development of the MSM.

Question 17

Limitation of Baddeley’s 1966 study

Answer 17

It used artificial stimuli. The words used had no personal meaning so tells us nothing about everyday memory. When processing meaningful information people use semantic coding even for STM- this means the study has limited application.

Question 18

Strength of Jacob’s 1887 study

Answer 18

It has been replicated and the findings have been confirmed. E.g Bopp and Vehaeghen in 2005.

Question 19

Limitation of Miller’s 1956 research

Answer 19

It may overestimate the STM capacity. Cowan in 2001 reviewed other research and concluded the capacity of STM was only about 4 +/- 1 chunks. Suggests that the lower end of Millers 7+/-2 estimate (5) is more accurate.

Question 20

Limitation of Peterson & Peterson’s 1959 study

Answer 20

Meaningless stimuli. (Not completely irrelevant though as we sometimes recall meaningless things) Recall of trigrams does not reflect everyday tasks, therefore lacks external validity.

Question 21

Strength of Bahrick et al.’s 1975 study

Answer 21

High external validity. Studied everyday meaningful memory of peoples faces. When other lab studies were done with meaningless pictures, recall rates were lower.