Coding, Capcity and Duration of Memory

Question 1

Define:

1) memory
2) coding
3) capacity
4) duration

Answer 1

1) ability to take in, retain and recall information at will
2) format in which memory is stored
3) amount of info that can be stored
4) how long info can be stored for

Question 2

What is the encoding, capacity and duration of the STM?

Answer 2

1. Acoustic
2. 7+/2 items
3. Up to 30 seconds without rehearsal

Question 3

What is the encoding, capacity and duration of the LTM?

Answer 3

1. Semantic
2. Potentially unlimited
3. Up to a lifetime

Question 4

Outline one study of coding.

Answer 4

1. Baddeley (1966)
2. Showed diff word lists to 4 ppt groups
   - acoustically sim and dissim
   - semantically sim and dissim
3. Ppts had to recall in correct order
4. STM test (immediately after) = worse performance w acou sim
5. LTM test ( after 20 min) = worse performance w seman sim
6. T.f. suggests info is coded seman in LTM

Question 5

Evaluate Baddeley (1966).

Answer 5

1. Used artificial stim = no meaning to ppts
2. Can’t generalise for diff mem tasks that req diff encoding
3. Limited generalisability

Question 6

Outline one study of capacity (Jacobs)

Answer 6

1. Jacobs (1887)
2. Digit span test - gave ppts set of digits; had to recall aloud in correct order
3. If correct, inc number of digits in set until cannot recall correctly
4. Mean d.s = 9.3, mean l.s = 7.3

Question 7

Evaluate Jacobs (1887).

Answer 7

1. Conducted long ago - early research = lack adequate control; Compromises validity
2. Supported by other studies - inc validity

Question 8

Outline one study of capacity (Miller).

Answer 8

1. Miller (1956)
2. Observations - noted that things come in 7s ; suggests capacity of STM is 7 items
3. Noted recall is easier w chunking

Question 9

Evaluate Miller (1956)

Answer 9

1. May have overestimated capacity
2. Cowan (2001) concluded cap = 4 chunks
3. Miller’s lower end est (5 items) may be more suitable

Question 10

Outline one study of duration (P&P)

Answer 10

1. P&P (1959)
2. 24 students
3. Trigram read to them, then counted backwards from 3 digit number (proof of interference) in intervals of 3, 6, 9, 12, 15 and 18 seconds (retention interval)
4. longer reten interval = worse perf
5. T.f. suggests STM has short duration

Question 11

Evaluate P&P (1959).

Answer 11

1. Artificial stim - doesn’t reflect irl use of mem

2. Lacks external validity

Question 12

Outline one study of duration (Bahrick))

Answer 12

1. Bahrick et al (1975)
2. 392 ppts between 17 and 74
3. Used yearbooks - photo recog test (50 photos) + free-recall of any names ppt remembered
4. Recall = 90% within 15 years of grad ; recall = 70% within 48 years of grad
5. T.f LTM has long duration

Question 13

Evaluate Bahrick et al (1975).

Answer 13

1. High ext valid - used meaningful mem’s

2. Lack control of EV - e.g. ppts may have unintent rehearsed by looking at yearbook over the years.

Question 14

How must evaluation arguments be written?

Answer 14

PEE