Short - and Long-term memory

Question 1

Explain what is meant by the term “capacity”

Answer 1

• A measure of how much can be held in memory. It is represented in terms of bits of information, such as number of digits

Question 2

AO1 Capacity

What is the difference in capacity between STM AND LTM?

Answer 2

• STM = limited capacity

- LTM = potentially infinite capacity

Question 3

AO1 Capacity

What did Joseph Jacobs (1887) find out about the capacity of STM?

Answer 3

• capacity assessed using digit span.
• average span for digits = 9.3 items
• average span for letters = 7.3 letters

Question 4

AO1 Capacity

Why is it easier it recall digits?

Answer 4

• only 9 digits whereas there’s 26 letters.

Question 5

AO1 Capacity

What did George Miller (1956) find about the span of immediate memory?

Answer 5

• span of immediate memory = 7 items, sometimes more or sometimes less. (7+-2)

Question 6

AO1 Capacity

How can we remember more according to George Miller?

Answer 6

• If we chunk things together - five words and five letters = we can remember more.

Question 7

AO3 Capacity

What research suggests that STM is even more limited than Miller suggested?

Answer 7

P: Criticism - Miller’s findings have not been replicated
E: Cowan (2001) reviewed studies & found = STM is likely to be limited to 4 chunks.
Research on capacity = 4 items was about the limit
This means that the lower end of Miller’s range is more appropriate (i.e 7-2 which is 5)
E: Suggests STM may not be as extensive as was thought

Question 8

AO3 Capacity

Does the size of the chunk matter?

Answer 8

P: Size of the chunk affects how many chunks you can remember
E: Simon (1974) = shorter memory span for larger chunks, such as 8-word phrases, than smaller chunks, such as one-syllable words.
E: Supports view that STM has a limited capacity and refines our understanding.

Question 9

AO3 Capacity

Is there individual differences in the capacity of STM in terms of digits?

Answer 9

P: Individual differences - capacity of STM - not the same for everyone.
E: Jacobs found, recall (digit span) increased with age = 8 year olds average = 6.6 digits whereas the mean for 19 year olds = 8.6 digits. Change could be due to changes in brain capacity, and/or the development of strategies such as chunking.

Question 10

Explain what is meant by the term ‘Duration’

Answer 10

• A measure of how long memory lasts before it is no longer available

Question 11

AO1 Duration

How did Lloyd Peterson and Margaret Peterson study the duration of STM?

Answer 11

• 24 students
• each participant tested over 8 trials
• each trial, participant given a consonant syllable and 3 digit number (e.g. THX 512)
• asked to repeat this after a retention interval of 3,6,9,12,15 or 18 seconds

Question 12

AO1 Duration

What did Lloyd Peterson and Margaret Peterson find when they tested the duration of STM?

Answer 12

• 90% correct after 3 seconds, 20% correct after 9 seconds, and 2% correct after 18 seconds

Question 13

What does Lloyd Peterson and Margaret Peterson’s findings suggest about STM?

Answer 13

STM has a duration less than 18 seconds

Question 14

AO1 Duration

How did Harry Bahrick et al (1975) test the duration of LTM?

Answer 14

• 400 people aged (17-74) on their memory of classmates
• A photo-recognition test from the participants yearbook or a free-recall test of participants listing the names they can remember of those graduating their class.

Question 15

AO1 Duration

What did Harry Bahrick et al (1975) find?

Answer 15

• Photo recognition - Participants tested after 15 years = 90% accurate - dropped to 70% accurate after 48 years
• Free recall - Participants tested after 15 years = 60% accurate - dropped to 30% after 48 years

Question 16

AO3 Duration

is the research done on STM artificial and useful in everyday lives?

Answer 16

P: Research investigating STM = artificial
E: Memorising consonant syllables doesn’t truly reflect everyday life = not meaningful. However we do try to memorise postcodes or numbers - fairly meaningful
E: Although the task was artificial, the study does have some relevance to everyday life.

Question 17

AO3 Duration

What is a criticism of Lloyd Peterson and Margaret Peterson’s study?

Answer 17

P: Study didn’t measure what it set out to measure - STM results = displaced.
E: In Peterson’s study participants were counting the number in their STM - this may displace or overwrite the syllables.
To solve this - Reitman (1974) - used sound instead of numbers because sound can’t displace verbal rehearsal.
E: This suggests that forgetting in Peterson’s study was due to displacement rather than decay (forgetting)

Question 18

Explain what is meant by the term ‘Coding’

Answer 18

• (also encoding) The way information is changed so that it can be stored in memory. Information enters the brain via the senses (e.g eyes and ears). It is then stored in various forms, such as visual codes (like a picture), acoustic codes (sounds) or semantic codes (the meaning of experience).

Question 19

AO1 Coding

What are the 3 ways in which information is stored in our memory?

Answer 19

1) Sounds (acoustic)
2) Images (visual)
3) Meaning (semantic)

Question 20

AO1 Coding
Give an example of acoustically similar but semantically different words
Give an example of semantically similar words but acoustically different words

Answer 20

• cat, cab, can ,cap ,max, mat, man, map

- great, large, gargantuan, huge, broad, long, tall, fat, wide, high

Question 21

AO1 Coding

What did Alan Baddeley find about acoustic and semantic information in STM and LTM? And what does it suggest?

Answer 21

• Difficulty remembering acoustically similar words in STM but not in LTM, whereas semantically similar words posed little problem for STM but led to muddled LTMs.
  Suggests:
  STM is largely encoded acoustically
  LTM is largely encoded semantically

Question 22

AO3 Coding

Is LTM solely semantic?

Answer 22

P: LTM usually semantic but not always
E: Frost (1972) - long term recall = visual and semantic categories
Nelson and Rothbart (1972) = found evidence of acoustic coding in LTM
E: Therefore it seems that coding in LTM is not simply semantic but can vary according to circumastance.

Question 23

AO3 Coding

Why is Baddeley’s methodology criticised?

Answer 23

P: Baddeley may have not tested LTM
E: In his study, STM was tested by asking participants to recall a word list immediately after hearing it. For LTM it was only after 20 minutes.
E: This casts doubt on the validity of Baddeley’s research because he wasn’t testing LTM after all.

Question 24

AO3

Is STM solely acoustic?

Answer 24

P: STM - not exclusively acoustic - visual also involved.
E: For example, Brandimote et al (1992) found that participants used visual coding in STM if they were given a visual task (pictures) and prevented from doing any verbal rehearsal in the retention interval ( they had to say ‘la la la’) before performing a visual recall task. Normally we ‘translate’ visual images into verbal codes in STM, but as verbal rehearsal was prevented, participantas used visual codes.
Other research shows STM = semantic ( Wickens et al. 1976)
E: Suggests that STM is not exclusively acoustic.