Coding, Capacity and Duration

Question 1

explain the procedure and findings of Baddeley’s study

Answer 1

Baddeley had participants learn a list of acoustically similar words - cat, cab, can - or acoustically dissimilar words - pit, few, cow

also, semantically similar words - great, large, big and dissimilar - good, huge, hot

findings: immediate recall worse with acoustically similar words - STM is acoustic

recall after 20 mins is worse with semantic similar words - LTM is semantic

Question 2

explain the procedure and findings of Jacobs study

Answer 2

researchers read four digits, they increased this until the participant cannot recall the order correctly - the final number = the digit span

average - participants could repeat 9.3 numbers and 7.3 letters in the correct order immediately after they were presented

Question 3

explain the procedure and findings of Miller

Answer 3

Miller observed that everyday things were in groups of sevens - music scales, days of the week , deadly sins etc

the span of STM is about 7 items, plus minus 2, but is increased by ‘chunking’ grouping digits, letters into meaningful units

Question 4

Peterson and Peterson’s consonant syllable study

Answer 4

24 students given consonant syllable to recall and a 3 digit number to count backwards from. the retention interval was varied from 3,6,12,15 or 18

after 3 seconds, average recall was around 80%

after 18 seconds, average recall was around 3%

STM duration without rehearsal is up to 18 seconds

Question 5

Duration LTM - Bahrick Yearbook photos

Answer 5

392 American participants aged between 17 and 74

1) recognition test:50 photos from high school yearbooks
2) free recall test- participants listed names of their graduating class

the recognition test - 90% accurate after 15 years, 70% accurate after 48 years

free recall - 60% recall after 15 years , 30% after 48 years

Question 6

Strength of Baddeley’s study is that it identified two memory stores:

Answer 6

later research showed there are exceptions to Baddeley’s findings, but STM is mostly acoustic and LTM mostly semantic

this led to the development of the multi-store model

Question 7

Limitation of Baddeley’s study is that it used artificial stimuli

Answer 7

words used had no personal meaning to the participants so tells us little about coding for everyday memory tasks

when processing more meaningful information, people use semantic coding, even for STM

means that the findings of this study have limited application

Question 8

Strength of Jacobs’ study - it has been replicated

Answer 8

old study and may have lacked adequate controls (e.g. confounding variables - such as participants being distracted)

despite this, Jacobs’ findings have been confirmed in later controlled studies (e.g. Bopp and Verhaeghen)

this shows that Jacobs’ study is a valid measure of STM

Question 9

Limitation of Miller’s research is it overestimates STM capacity:

Answer 9

e.g. Cowan reviewed other research - concluded that the capacity of STM was only about 4 (plus minus 1) chunks

suggests that the lower end of Miller’s estimate was more appropriate than 7

Question 10

Limitation of Peterson and Peterson’s study is meaningless stimuli

Answer 10

We sometimes try to recall meaningless information so the study is not completely irrelevant

but recall of consonant syllables does not reflect meaningful everyday memory tasks

therefore the study lacked external validity

Question 11

One strength of Bahrick’s study is it had high external validity

Answer 11

everyday meaningful memories were studies - when lab studies were done with meaningless pictures to be remembered, recall rates were lower - Shepard

means that Bahrick’s findings reflect a more ‘real’ estimate of the duration of LTM