features of memory

Question 1

what are the 3 features of memory?

Answer 1

capacity, duration, encoding

Question 2

what is capacity?

Answer 2

how much can be held in the memory. there is no upper limit to the capacity of long term memory

Question 3

what was Jacob (1887) research into the capacity of the short term memory?

Answer 3

he conducted an experiment using a digit span test, to examine the capacity of short term memory for numbers and letters. participants had to repeat back a string of numbers or letters in the same order and the number of digits/letters was gradually increased, until the participants could no longer recall the sequence.
Jacobs found that the mean span for digits across all participants was 9.3 items. the mean span for letters was 7.3.

Question 4

what was Miller (1956) research into the span of memory and chunking?

Answer 4

he reviewed previous research into the STM. he noted that in everyday life, things come in sevens:
7 notes on the musical scale, 7 days of the week, 7 deadly sins etc…
this suggests that the span (or capacity) of the short term memory is about 7 items. (plus or minus 2) 7+/-2

Question 5

what is the capacity of long term memory?

Answer 5

there is no upper limit to the capacity of long term memory

Question 6

what is duration?

Answer 6

it is how long a memory lasts before its no longer available

Question 7

what is the length of the short term memory’s duration and what is the STMs duration?

Answer 7

18-30 seconds but it can be increased if rehearsed
the STM has a brief duration as a temporary store, anything needed o be remembered for longer is transferred to the LTM

Question 8

what is Peterson&Petersons research into the duration of the short term memory?

Answer 8

• they conducted a lab experiment with 24 psychology students
• they looked at how long the STM lasts if rehearsal is prevented
• the students had to recall meaningless 3 letter constonant trigrams (e.g. THG, XWV) the delay between being shown the trigram and asked to recall it varied between participants- e.g. recall at one of the following intervals: 3, 6, 9, 12, 15 or 18 seconds
  FINDINGS:
  80% of trigrams were remembered after 3 second delay, 50% after 6 second delay, 10% or less recalled at 18 second delay
  CONCLUSION:
  the short term memory has a limited duration of approximately 18 seconds.
  if we can’t rehearse information it wont be passed onto the LTM

Question 9

what is Bahrick et al. (1975) research into the duration of the LTM?

Answer 9

• was a natural experiment
• opportunity sample of 392 ex-high school students aged 17-74
• tested for memory and portraits of classmates selected from yearbooks
• the graduates were shown photographs from their high school year book and for each photograph participants were given a group of names and asked to select the name that matched the photographs.
  FINDINGS:
• 90% accuracy in face and name recognition, even in those participants who had left high school 34 years previously
• after 48 years this declined to 80% for name recognition and 40% for face recognition
  CONCLUSION:
  people could remember certain types of information, such as names and faces for almost a lifetime. these results support the multi-store model and the idea that our long term memory has a lifetime duration (at least 47 years)

Question 10

what is encoding?

Answer 10

it refers to the way information is changed into a code so it can be stored in memory

Question 11

what are the 3 kinds of coding systems?

Answer 11

• visual (as an image)
• acoustic (as a sound)
• semantic (through a meaning)

Question 12

what is the main coding system in the STM?

Answer 12

acoustic

Question 13

what is the main coding system in the LTM?

Answer 13

semantic

Question 14

what is Baddeleys (1966) research into the encoding of the STM?

Answer 14

AIMS:
lab experiment to investigate coding in the short-term memoir store (converting information from one form to another)
METHOD:
participants were given a list of words that were:
- acoustically similar ( e.g. cat, mat, cap, map …)
- acoustically different (e.g. dog bin, cup, pen …)
- semantically similar (e.g. big, large, huge, vast …)
- semantically different (e.g. huge, good, light, blue …)
FINDINGS:
in the STM, acoustically similar words were much harder to recall in the correct order than semantically similar words e.g. they would confuse cat, cap etc (when testing the LTM this was not the case)
CONCLUSION:
in the STM, information is encoded acoustically, STM relies more on the sound of words than on their meaning as recall is affected by the sounds of words, when we recall information from the STM, similar sounding words get confused.
this study supports the view that the STM and LTM are separate.

Question 15

what is Baddeley (1966) research into the encoding of the LTM?

Answer 15

he set up a lab experiment where participants were given a list of words (same as STM) and asked to recall them after a time internal of 20 minutes
FINDINGS:
participants had problems remembering semantically similar words in LTM but not acoustically similar words
CONCLUSION:
in LTM information is encoded semantically- it best remembers meanings rather than sounds

Question 16

what is the features of memory table?

Answer 16

STM LTM
coding acoustic semantic
capacity 7+/-2 potentially unlimited
duration 18-30 secs hours,days,years

Question 17

AO3: what is a strength to Baddeleys research into the features of memory?

Answer 17

one strength to Baddeleys research is that its a relaible study. this is because it has standardised procedures so you could replicate it yourself. you wouldn’t need any special equipment and you could use exactly the same words as Baddeley.

Question 18

AO3: what is a limitation to Baddeleys research into the features of memory?

Answer 18

one limitation to Baddeleys study is that he used quite artificial stimuli rather than meaningful material. the word list has no personal meaning to participants. this means that we should be cautious about generalising the findings to different memory tasks. for example, when processing more meaningful information, people may use semantic coding even for STM tasks. this suggests that the findings from this study have limited application.

Question 19

AO3: what is a limitation to Millers research into the features of memory?

Answer 19

one limitation to Millers research is that he may have overestimated the capacity of the STM. for example. Cowan (2001) reviewed others research and concluded that the capacity of the STM was only 4 chunks. this suggests that the lower end of Millers estimate (5 items) is more appropriate than 7 items.

Question 20

AO3: what is a limitation to Peterson&Petersons research into the features of memory?

Answer 20

a limitation to Peterson&Petersons study is that the stimulus material was artificial. trying to memorise costenant syllables does not reflect most real life memory activities where what we are trying to remember is meaningful. this study, therefore, lacked external validity. however, we do sometimes try to remember fairly meaningless things, such as, phone numbers, so the study isn’t irrelevant.

Question 21

AO3: what is a strength to Bahricks research into the features of memory?

Answer 21

one strength to Bahricks study is that it has higher external validity. real life meaningful memories were studied. when studies on the LTM have been conducted with meaningless pictures to be remembered, recall rates were lower (e.g. Shepard 1967). however, the downside of such real life research is that confounding variables are not controlled, such as the fact that Bahricks participants may have looked at their yearbook photos and rehearsed their memory over the years.