Coding, capacity and duration

Question 1

What is coding?

Answer 1

The format in which information is stored, in various memory stores

Question 2

What is capacity?

Answer 2

The amount of information that can be held in a memory store

Question 3

What is duration?

Answer 3

The length of time information can be held in memory

Question 4

What is short-term memory?

Answer 4

The limited capacity memory store. In STM, coding is mainly acoustic, capacity is between 5-9 items, and duration is about 18 seconds

Question 5

What is long term memory?

Answer 5

The permanent memory store. In LTM, coding is mainly semantic, it has unlimited capacity and can store memories for up to a lifetime

Question 6

Who researched coding?

Answer 6

• Baddley

Question 7

Who researched capacity?

Answer 7

• Jacobs
• Miller

Question 8

Who researched duration?

Answer 8

• Peterson and Peterson
• Bahrick et al

Question 9

What did Baddeley’s research into coding entail and what were the findings?

Answer 9

• Gave lists of words to 4 groups:
  1: acoustically similar
  2: acoustically dissimilar
  3: semantically similar
  4: semantically dissimilar
• Participants given words to recall in the correct order
• When asked immediately (STM)- acoustically similar was worst
• When asked after 20 mins (LTM)- semantically similar was worst
• Info coded acoustically in STM and semantically in LTM

Question 10

What did Jacobs research into capacity entail and what were the findings?

Answer 10

• Measured digit span
• Researcher reads 4 digits aloud and participant recalls in correct order aloud
• If correct, researcher reads 5 digits, then 6 and so on
• Found mean span for digits across participants= 9.3 items
• Mean span for letters= 7.3

Question 11

What did Miller’s research into capacity entail and what were the findings?

Answer 11

• Made observations of everyday practice
• Noted all things come in 7s (days of week, deadly sins, etc)
• Miller thought span of STM is 7 (+ or - 2)
• Recall letters and words by chunking

Question 12

What did Peterson and Peterson’s research entail and what were the findings?

Answer 12

• 24 students in 8 trials each
• On each trial, participant given a consonant syllable to remember
• Also given a 3 digit number
• Counted backwards from number until told to stop
• On each trial, they were told to stop after varying periods of time
• After 3 seconds, average recall= 80%, after 18 seconds, recall= 3% (STM)

Question 13

What did Bahrick et al’s research entail and what were the findings?

Answer 13

• 392 American participants between 17 and 74
• Recall 1: photo recognition from high school yearbooks (50 photos)
• Recall 2: Free recall test, where participants recalled names of their graduating class
• Within 15 years of graduation= 90% accurate in photo recall and 60% in free recall
• After 48 years= 70% photo recognition and 30% free recall
• Suggests LTM can last a lifetime

Question 14

What is the main strength of coding research?

Answer 14

I= identified a clear difference between two memory stores
D= STM uses acoustic coding and LTM uses semantic coding
E= led to development of multi-store model

Question 15

What is the main limitation of coding research?

Answer 15

I= use of artificial stimuli rather than meaningful material
D= word lists had no personal meaning to participants, so findings tell us little about coding in everyday life. When processing more meaningful info, semantic coding is used even for STM
E= Suggests findings have limited application

Question 16

What is the main strength of capacity research?

Answer 16

I= findings have been replicated
D= Jacob’s study lacks adequate controls. E.g: digit spans underestimated due to distractions. But findings confirmed by other, better controlled studies (Bopp and Verhaeghen)
E= Provides external validity

Question 17

What is the main limitation of capacity research?

Answer 17

I= overestimated capacity of STM
D= Cowan reviewed other research and concluded the capacity of STM is about 4 chunks (+ or - 1)
E= suggests lower end of Miller’s estimate is more accurate than 7

Question 18

What is the main strength of duration research?

Answer 18

I= High external validity in Bahrick’s study
D= Investigation of meaningful memories (names and faces). When LTM studies were conducted with meaningless pictures, recall was lower
E= findings reflect a more accurate estimate of duration of LTM

Question 19

What is the main limitation of duration research?

Answer 19

I= artificial stimuli in Peterson and Peterson’s study
D= Consonant syllables are meaningless and do not reflect everyday memory activities
E= lack of external validity