Coding, Capacity & Duration Flashcards
What is the coding for short-term memory?
Acoustic
What is the coding for long-term memory?
Semantic
What is the capacity of short term memory?
7+ or -2 items
What is the capacity of long-term memory?
Unlimited
What is the duration of short term memory?
0 to 18 seconds (without maintenance rehearsal)
What is the duration of long-term memory?
It can be up to a lifetime or unlimited
What is the study linking to the coding of STM & LTM?
Baddeley in 1966 – word list - some acoustically or semantically similar.
STM of acoustically similar words was worse. LTM of semantically similar words was worse.
The study had an artificial stimulus so had low ecological validity and generalisability.
What is the study linking to the capacity of short term memory?
Jacobs in 1887 – digit span – recall tested – digit added.
The mean number of digits remembered was 9.3 and the mean number of letters 7.3.
Study was conducted a long time ago - less control of extraneous variables.
What is another study linking to the capacity of long-term memory?
Miller 1956 – review of the studies and found things coming sevens. The capacity of short term memory for 7+ or -2 items but chunking increases this amount.
May have overestimated – Cowan in 2001 -4 not 7
What is the study link into the duration of short term memory?
Peterson and Peterson in 1959 – tested the memory of consonant syllables and three digit numbers without rehearsal.
After three seconds - 80% recall so short-term memory was less than 18 seconds without maintenance rehearsal.
It was an artificial stimulus and a biased sample – students.
What is the study linking to the duration of long-term memory?
Bahrick et al. 1975 -recognition test of faces or free recall – yearbook. Faced recognition after 48 years was 90% free recall was only 30% shows long-term memory lasts a long time.
Rehearsal may’ve influence the results - some people may have looked at the yearbook more than others but has high external validity.
