Coding, Capacity & Duration

Question 1

coding definition

Answer 1

the process of converting info between different forms

Question 2

coding research example

Answer 2

BADDELEY (1966)
- different lists of words given to 4 groups
- acoustically similar & dissimilar, semantically similar & dissimilar
- shown them then asked to recall in order
- recalling immediately (STM) = worse with acoustic similar
- after 20 mins (LTM) = worse with semantic similar

Question 3

evaluation of baddeley (1966)

Answer 3

STRENGTH
- separate memory stores = identified a clear difference between 2 stores (with some exceptions) which had stood the test of time - led to MSM
LIMITATION
- artificial stimuli rather than meaningful material = words had no personal meaning so may not reflect everyday life - people may use semantic for STM too, so LIMITED APPLICATION

Question 3

what does the coding study suggest?

Answer 3

that info is coded acoustically in STM & semantically in LTM

Question 3

capacity definition

Answer 3

how much info something can hold at one time

Question 4

digit span capacity research example

Answer 4

JACOBS (1887)
- reads 4 digits out loud & gets participant to recite back in order - if correct, 5 digits & so on until incorrect
- mean span (digits) = 9.3
- mean span (letters) = 7.3

Question 5

evaluation of jacobs’ work

Answer 5

STRENGTH
- valid study = has been replicated by other better controlled studies (bopp & verhaegh 2005) despite it being an early study

Question 6

memory span & chunking capacity research example

Answer 6

MILLER (1956)
- observations of everyday practices - noted things came in 7s (musical scale, days in week, deadly sins)
- thought STM capacity was 7 +/- 2 items
- noted we can recall 5 letters as well as 5 words - done by chunking

Question 7

evaluation of miller’s research

Answer 7

LIMITATION
- overestimation of STM capacity? = nelson cowan (2001) reviewed other research & concluded it’s 4+/-2 items

Question 8

duration definition

Answer 8

length

Question 9

STM duration research example

Answer 9

PETERSON & PETERSON (1959)
- 24 students, 8 trials each
- given a trigram then given a number & had to count backwards in 3s from it (preventing mental rehearsal)
- told to stop after varying times (3, 6, 9, 12, 15 & 18 secs)
- after 3 secs = average recall 80%
- after 18 secs = average recall 3%

Question 10

what did peterson & peterson’s research suggest?

Answer 10

that STM duration was on average 18 secs without mental rehearsal

Question 11

evaluation of peterson & peterson

Answer 11

LIMITATION
- meaningless stimuli - artificial, but not completely irrelevant as we do try to memorise things like phone numbers but doesn’t reflect most daily memory activities
- lacks EXTERNAL VALIDITY

Question 12

LTM duration research example

Answer 12

BAHRICK ET AL (1975)
- 392 american participants ages 17-74
- recall of high school class tested with photo recognition & free recall
- tested within 15 years (photo) = 90%
- after 48 years (photo) = 70%
- 15 years (free) = 60%
- 48 years (free) = 30%

Question 13

what did bahrick’s study suggest?

Answer 13

that LTM may last a lifetime for some material

Question 14

evaluation of bahrick’s study

Answer 14

STRENGTH
- high external validity = investigation of meaningful memories
- when studies had meaningless pictures, recall was lower (shepard 1967)