Coding, Capacity and Duration Flashcards
who is the researcher involved in the research of coding of memory?
Baddeley
what did Baddeley do to test the coding of memory?
- gave different lists of words to 4 groups to remember
- groups: semantically similar, semantically dissimilar, acoustically similar and acoustically dissimilar
- ppts were shown original words and asked to recall in correct order
- when they were asked to do this immediately, recalling from STM they tended to do worse with acoustically similar words
- when asked to recall words after 20 mins, they tended to do worse with semantically similar words
what does Baddeley’s research on coding show?
- STM = acoustically
- LTM = semantically
who is the researcher involved in the research of capacity of memory?
Jacobs
how did Jacobs research capacity?
measuring digit span
what did Jacobs do to test the capacity of memory?
- read out 4 digits and asked ppts to recall in the correct order and if they did he’d move to 5 and so on
what did Jacobs find the mean digit and letter spans to be?
9.3 items = digits
7.3 items = letters
this is because there are more letters than digits
what is chunking?
grouping sets of digits or letters into units or chunks
what is the capacity of STM?
7 plus or minus 2
who investigated chunking?
Miller
how did Miller investigate chunking?
- made observations of everyday practices: 7 days of the week, seven deadly sins and seven notes on musical scale
who is the researcher involved in the research of duration of memory(STM)?
Peterson and Peterson
how did Petersons investigate the duration of STM?
- tested 24 students in 8 trials
- each trial they were given a consonant syllable and a 3 digit number they had to count backwards from this number until told to stop
- and on each trial they were told to stop at varying times = 3,6,9,12,15,18 seconds (retention interval)
what would counting backwards from do when researching the duration of STM?
prevent any mental rehearsal of the consonant syllable
what was the findings of Petersons’ study?
- 3 seconds = average recall was 80%
- 18 seconds = average recall was 3%
what did the findings of Peterson and Peterson suggest about the duration of STM?
18 seconds unless we repeat the information(verbal rehearsal)
who is the researcher involved in the research of duration of LTM?
Bahrick et al
how did Bahrick et al investigate the duration of LTM?
- studied 392 American ppts aged between 17 to 74
- high school yearbooks were obtained and recall was tested in various ways
1) photo-recognition test consisting of 50 photos some from the ppts high school yearbooks
2) free recall test where ppts would recall all the names of their graduating class
what was the findings of Bahrick et al?
- ppts tested within 15 yrs of graduation = 90% accuracy in photo recognition
- after 48 yrs = recall declined 70% accuracy for photo recognition
- free recall was less accurate, about 60% after 15 years, dropping to 30% after 48
what did the findings of Bahrick’s et al suggest about the duration of LTM?
lasts for a lifetime
what are the evaluations for research of coding?
+ clear difference between two memory stores
- Baddeley uses quite artificial stimuli
what are the evaluations for research of capacity?
+ can be replicated
- Miller may have overestimated STM capacity
what are the evaluations for research of duration?
+ high external validity
- stimulus material was meaningless
