coding capacity and duration Flashcards
what happens when information gets into the memory system
it is stored in different formats. The way its stored depends on the memory store
what is coding
the process of converting information from one form to another
describe one research into the coding of memory (STM and LTM)
Alan Baddeley (1966a, 1966b) gave different lists of words to four groups of participants to remember:
Group 1: (acoustically similar) words that sounded similar e.g. cat, cab, can
Group 2: (acoustically dissimilar) words sounded different e.g. pit, few, cow
Group 3: (semantically similar ) words with similar meanings e.g. great, large, big
Group 4: ( semantically dissimilar) words that all had different meanings e.g. good, huge, hot
what does Baddeley’s research into coding tell us (STM and LTM)
participants were shown the original words and asked to recall them in the correct order
when they had to this recall task immediately after hearing it (STM recall) they tended to do worst with acoustically similar words . Thus suggests that STM is acoustically coded
If participants were asked to recall the word list after a time interval of 20 minutes (LTM recall), they did worse with the semantically similar words. This suggest that information is coded semantically on LTM
what is capacity/ digital span (STM)
the capacity is how much info a memory store e.g. STM can hold any one time
describe one research into capacity (STM)
Joseph Jacobs (1889) developed a technique to measure digital span
Procedure:
1. the researcher gives, e.g., 4 digits and then the participants is asked to recall these in the correct order out loud
- researcher reads out 5 digital and so on until the participants cannot recall the order correctly
what did Joseph Jacob research show (STM)
this research determined the individual’s digit span
the mean digits for digits across all participants were 9.3 items and for letters 7.3
describe another research into capacity (STM)
George Miller (1956) made observations of everyday practice
PROCEDURE:
e.g. he noted that things come in sevens: there are 7 notes on the musical scale, 7 days in the week
This suggests that the capacity/ span of STM is about 7 items ( plus or minus 2)
7+/-2
what else did Miller note ( chunking)
Miller also noted that people can recall 5 words as well as they can recall 5 letters by chunking/ grouping sets of digits or letters into units or chunks
what is duration
duration is how long information can be stored
describe some information into duration (STM)
Margret and Lloyd Peterson (1959) tested 24 undergraduate students
PROCEDURE
Each student took part in eight trials ( a trial being one test)
On each trial the student was given a consonant syllable ( also known as a trigram such as YCG) to remember and was also given a 3- digit number
students were told to count backwards from that digit number until they were told to stop . This is to stop any metal rehearsal of the consonant syllable ( this would increase the student’s memory for consonant syllable)
on each trial they were told to stop at different times e.g. at 3, 6, 9,12,15 or 18 seconds. This is called the retention interval.
what does Margaret and Lloyd suggest about the duration of STM
the findings suggests that STM may have a very short duration unless we repeat something over and over again ( verbal rehearsal)
If not repeated the information would be forgotten after 18 - 30 seconds
therefore the duration for STM is 18 - 30 seconds
what is some research into the duration of the duration of LTM
Harry Bahrick and colleagues (19775) studied 392 participants from American state of Ohio
PROCEDURE
high school yearbooks were obtained from participants or from schools
recall was tested in various ways e.g. photo recognition test consisting of 50 photos, some from the participants high school yearbook
free recall test where participants recalled all thee names of their graduating
what were the findings of Harry Bahrick
- participants who were tested within 15 years of graduating were about 90% accurate in photo recognition
48 years 70% for photo recognition
free recall was less good 15 years - 60% accurate
30% after 48 years
This shows that LTM can last a very long time needed ( unlimited)
what is the coding for LTM
unlimited
