Section 2 : Memory - Types of Memory

Question 1

Research on Coding
Baddeley

Answer 1

Coding - process of converting memory between different stores

Method:
4 differnt lists of words
-acoustically similar
-acoustically disimilar
-semantically similar
-semantically disimilar
Participants shown list, asked to recall in order
Recall:
Immediate, STM
20 mins later, LTM

Results:
STM - worse when acoustically similar
LTM - worse when semantically similar

Conclusions:
Info coded acoustically in STM
Info coded semantically in LTM

Question 2

Research on Coding
Evaluate Baddeley

Answer 2

• lacks ecological validly
• other types of LTM (procedural, episodic memory) which this study doesn’t consider
• other methods of coding (visual) which this study doesn’t consider
• independent groups design means no control over participant variables

Question 3

Research on Capacity
Jacobs

Answer 3

Digit Span
Method:
-Read out a list of digits
-Participants asked to recall in correct order
-Length of list increased if participant correctly recalled last number

Results:
Mean span of:
Digits - 9.3
Letters - 7.3
this capacity increased with age during childhood

Conclusions:
-STM has a capacity of 5-9
- Individual difference were found as STM increases with age, possibly due to memory techniques e.g. chunking
- digits may have been easier to recall as there were only 10 different digits to remember compared to 26 letters

Question 4

Evaluate Jacobs research on capacity - digit span

Answer 4

Strength
Been replicated

Jacobs - old study, may have lacked control
Eg digit spans may have been underestimated eg due to distractions - cofounding variable

BUT
Same conclusions from Bopp and Verhaeghen

Increases validity for test of digit span in STM

WEAKNESS
artificial research, lacks ecological validity

Question 5

Research on Capacity
Span of memory and chunking

Answer 5

Miller
Observations of every day practive
eg 7 days of week

Concluded
-Capacity of STM is 7 +-2
-People recall 5 words as easily as 5 letters due to chunking

Question 6

Evaluate Millers Span of Memory and chunking

Answer 6

Weakness
May have overestimated STM capacity

Cowan - reviewed research, concluded capacity of STM is 4 +-1 chunks

Suggests - Miller overestimated

Question 7

Research on duration
Duration of STM

Answer 7

Margaret and Peterson
24 students, 8 trials
one trial - consonany syllable to remember and 3 digit number
Count back from number, preventing mental rehersal (rehersal would increase the duration of the STM)

Retention interval - Asked to stop after specific time intervals eg 3, 6, 9 seconds

Results - 2 seconds avg recall 80%, 18 seconds 3%

STM about 18 seconds without rehersal

Question 8

Evaluate Research of Duration
Peterson - STM

Answer 8

Weakness

Stimulus material was artificial

BUT - sometimes try remember meaningless info eg phone numbers

BUT - does not reflect everyday tasks

Lacks external validity

Question 9

Research on duration
Duration of LTM

Answer 9

Bahrick
392 American students, 17 to 74

Highschool yearbooks,
1 - photo recognition test, 50 photos
2 - free recall test, all names of graduating class

Photo Results
Tested within 15 years of graduation
-90% accurate recall
48 years
-70% accurate recall

Free recall
After 15 years
-60% accurate
After 48 years
-30% accurate

LTM may last forever

Question 10

Evaluate
Research on duration - LTM
Bahdrick

Answer 10

Strength

High external validity

Research investigated meaningfull memories eg names

More realistic results for duration of LTM

Question 11

What are the three types of memory

Answer 11

• sensory register
• short-term memory
• long-term memory

Each differ in duration (how long it lasts), capacity (how much can be held), coding (how it is stored)

Question 12

What is the sensory register

Answer 12

• stores information from our senses (sight, sound, touch, taste, smell)
• unless we pay attention to it, it disappears quickly through spontaneous decay
• has a limited capacity and very limited duration
• information is coded depending on the sense that it has picked up (visual, auditory, tactile etc.)

Question 13

What is the short term memory

Answer 13

• limited capacity memory store
• coding is usually acoustic (sound)
• capacity 5-9 pieces of information
• duration 18s

Question 14

What is long term memory

Answer 14

• permanent memory store
• coding is usually semantic
  -unlimited capacity and duration

Question 15

What are the three types of long term memory

Answer 15

• Episodic memory
• semantic memory
• procedural memory

Question 16

define coding

Answer 16

information transformed in to a format in which it can be stored and retrieved from meory

Question 17

What is episodic memory

Answer 17

• Stores information about events that you’ve actually experienced, e.g. concert
• stores facts and knowledge that we have learnt and can consciously recall
• does not contain details of time or place where you learnt the information

Question 18

What is procedural memory

Answer 18

• stores knowledge of how to do things e.g. walking
• this information can’t be consciously recalled

Question 19

What did sterling investigate

Answer 19

Investigated the sensory register using brief displays

Question 20

What was the method of Sperling 1960

Answer 20

• Lab experiment
• shown a grid with three rows of four letters for 50 milliseconds (0.05s)
• then they had to immediately recall either the whole grid or a randomly chosen row

Question 21

What was the results of Sperling 1960

Answer 21

• when recalling the whole grid they only managed to recall 4 or 5 letters on average
• when a recalling a row, participants could recall 3 items average no matter which row

Question 22

what was the conclusion of sperling 1960

Answer 22

• the participants didn’t know which row was going to be selected , so in theory they would have been able to recall items from any row meaning almost the whole grid was held in their sensory register
• they couldn’t report the whole because the trace faded before they could finish recall

Question 23

what are the evaluations of Sperling 1960

Answer 23

• lab experiment, variables could be controlled and easily replicated
• lacks ecological validity, people don’t normally have to recall letters in response to a sound so results might not represent what would happen in the real world

Question 24

what was the method of peterson and peterson

Answer 24

• participants were shown nonsense trigrams (3 random consonants e.g. CVH) and asked to recall them after 3, 6, 9, 12, 15, 18 seconds
• during the pause they were asked to count backwards in threes from a given number
• this interfered with the participants so they wouldn’t repeated the

Question 25

what were the results of peterson and peterson

Answer 25

• after 3 seconds participants could recall about 80% of trigrams correctly
• after 18 seconds only about 10% were recalled correctly

Question 26

what was the conclusion of peterson and peterson

Answer 26

when rehearsal is prevented very little can be held in the STM for longer than 18 seconds

Question 27

what was the evaluations of peterson and peterson

Answer 27

+ lab experiment, variables were tightly controlled
- nonsense trigrams we’re artificial so lacks ecological validity
- meaningful or real life memories may last longer in the STM
- only one type of stimulus was used; the duration of STM may depend on the type of stimulus
- each participant saw many different trigrams, could have led to confusion meaning that the first trigram was the only realistic trial

Question 28

What was the method of Bahrick et al 1975

Answer 28

• 392 ppts asked to list names of ex classmates (free recall)
• they were shown photos and asked to recall names of the people shown (photo-recognition test)
• or given names and asked to match them to a photo of the classmate (name-recognition test)

Question 29

What was the results of Bahrick et al

Answer 29

• within 15 years of leaving school, participants could recognise about 90% of faces and names and they were about 60% accurate on free recall
• after 30 years, free recall had declined to about 30% accuracy
• after 48 years name-recognition was about 80% accurate and photo recognition about 40% accurate

Question 30

What was the conclusion of Bahrick et al 1975

Answer 30

• The study is evidence of Very Long term memories in a real life setting.
• recognition is better than recall, so there may be a huge store of information but not always easy to access all of it; you just need help to get to it

Question 31

What was the evaluations of Bahrick et al 1975

Answer 31

+ field experiment, high ecological validity
+ showed better recall than other LTM studies
- hard to control all variable in field experiments, makes findings less reliable
- info recalled may be because it was meaningful and therefore stored better
- this type of info could be rehearsed (still in touch with classmates etc.) increases the rate of recall
- results can’t be generalisable to other types of info held in the LTM

Question 32

What is Miller’s Magic number

Answer 32

Seven plus or minus 2

Question 33

What did miller suggest to make sequences more meaningful

Answer 33

We use chunking, e.g. if the sequence is 20031987 we chunk it to become 2003 1987 so it becomes more easier to remember

Question 34

How do we try to keep information in the STM

Answer 34

By actively repeating it to ourselves, generally involving acoustic coding (about how the info sounds)

Question 35

How do we try to keep information in our long term memory

Answer 35

Generally semantic coding (about the meaning of the information), it’s more useful to code words in terms of their meaning, rather than what they sound or look like however can also be coded thru visual and acoustic