Duration, Capacity, Encoding: MEMORY Flashcards
Duration of short term memory
Who developed this?
Approximately 18-32 seconds
Perterson and Perterson (1959)
Duration of long term memory
Who developed this?
Up to a lifetime
Harry Bahrion 1975
Capacity of short term memory
Which 2 psychologists developed this?
7 +/- two items
Miller 1951
Jacobs (1887)
Capacity of long term memory
Unlimited
In which 3 ways is memory coded?
Define these
Visually: by the use of images and what we see
Auditory: by the use of Auditory information (sound) and what we hear
Semantic: by the meaning of the information
Define coding in memory
The format in which information is stored in the various memory stores
In what format is long term memory stored?
Who conducted experiments to determine this?
Semantically
Baddely (1966)
I’m what format is short term memory stored?
Acoustically
Peterson and Peterson sample procedure and findings
Peterson & Peterson (1959) investigated the duration of short-term memory by conducting a laboratory experiment with a sample of 24 psychology students.
The students had to recall meaningless three-letter trigrams (for example, THG, XWV) at different intervals (3, 6, 9, 12, 15 or 18 seconds). To prevent rehearsal (practice) the students had to count backwards in threes or fours from a specific number, until they were asked to recall the letters.
Peterson & Peterson found that the longer the interval the less accurate the recall. At 3 seconds, around 80% of the trigrams were correctly recalled, whereas at 18 seconds only 10% were correctly recalled.
Peterson & Peterson concluded that short-term memory has a limited duration of approximately 18 seconds. Furthermore, the results show that if we are unable to rehearse information, it will not be passed to long-term memory, providing further support for the multi-store model and the idea of discrete components.
Bahrick procedure
(1975)
-studied 392 American participants aged 17-74
-obtained yearbooks from p.p or school
-recall tested via photo recognition or by name
Found: p.p tested within 15 years of graduating 90% accurate
-after** 48 years, photo recognition declined to 70.5%**
Free call overall less accurate
Research into capacity of STM procedure
Jacobs studies digit spans.
Researcher gives e.g: 4 digits to participant who is asked to recall in the correct order out loud. The number of digits is increased by one until participant can’t recall correctly.
This determines digit span.
Findings of Jacobs study
Mean span for digits across all p.p was 9.3 items. For letters it was 7.3
