MEM 02 - Capacity & Duration Flashcards
What is STM?
The limited capacity memory store.
What is LTM?
The permeanent memory store.
What is capacity?
The amount of information that can be held in memory.
What is duration?
The length of time information can be held in memory.
What is capacity?
The format in which information is stored in various memory stores.
Who discovered how STM and LTM are coded? And when?
Alan Baddeley (1966a, 1966b)
What was the procedure of Alan Baddeley’s study on the coding of LTM and STM?
He gave a list of different words to 4 groups:
- Group 1 had a list of words that sounded similar
- Group 2 had a list of words that sounded different
- Group 3 had a list of words that had similar meanings
- Group 4 had a list of words that had dissimilar meanings
Participants were shown the original words and asked to list them out in the correct order.
What is the findings of Alan Baddeley’s study in terms of the MSM?
- When they did this task immediately, recalling from STM, participants did worse with acoustically similar words.
- When they did this task after a certain interval, 20 minutes, recalling from LTM, participants tended to do worse with semantically similar words.
- This study showed that STM is coded acoustically and LTM is coded semantically,
Who discovered the capacity of STM? And When?
Joseph Jacobs (1887) and George Miller (1956)
What was the procedure of Joseph Jacob’s study?
- Jacobs conducted a study using a digit span test.
- He used a sample of 443 female students (aged 8-19) from the North London Collegiate School.
- Participants has to repeat back a string of numbers or letters in the same order and the number of digits/letters was gradually increased, until the participants could no longer recall the sequence.
What was the conclusion of Jacob’s study?
Participants had a mean digit span of 9.3 items and a mean span of 7.3 letters.
What was the procedure of George Miller’s study? And what did he conclude?
- Miller made observations of everyday practices and noticed that things come in sevens e.g. notes on a musical scale, days of the week, seven deadly sins.
- He also noticed that we recall 5 words as easily as 5 letter. We do this by chunking i.e. grouping sets of digits or letters into units or chunks.
- He concluded that the span of STM was 7+/-2 chunks or items.
Who discovered the capcity and duration of LTM? And when?
Harry Bahrick et al (1975)
What was the procedure of Bahrick’s study?
- He studied 392 american participants aged between 17 and 74.
- High school yearbooks were obtained from the participants or directly from some schools.
- Recall was tested in various ways e.g. photo recognition consisting of 50 photos and free recall where participants recalled all the names of their graduating class.
What was the findings of Bahrick’s?
- Participants tested within 15 years of graduation were about 90% accurate in photo recognition.
- After 48 years, recall declined to about 70% for photo recognition.
- Free recall was less accurate than recognition - about 60% after 15 years, dropping to 30% after 48 years.
- This shows that LTM may last up to a lifetime for some material.