Coding, Capacity, Duration Flashcards
(22 cards)
What does coding mean?
Sensory info modified and stored in brain
What is duration?
Length of time info can be stored in memory
What is capacity?
Amount of info stored in memory
Three types of coding?
Visually, acoustically, semantically
Capacity of Sensory register?
Very large
Capacity of STM
7+/-2 items
Capacity of LTM
Potentially unlimited
What was Jacobs (1887) study?
- digit span task to assess STM capacity
- numbers average = 9.3 items
- letter average = 7.3 items
What did George Miller (1956) say?
- ‘magic number is 7 plus or minus 2’
What is Chunking?
- George Miller
- capacity increased if chunk items together (FBI, AQA)
Limitation of Capacity - Point
Miller’s research overestimated STM capacity
Limitation of Capacity - Evidence
Cowen (2001) concluded that STM capacity is closer to 4 chunks of information
Sensory Register duration?
Less than one second
STM duration?
18-30 seconds unless rehearsed
LTM duration?
Potentially infinite
Peterson and Peterson (1959) study?
- STM duration - STM has limited duration with recall accuracy declining significantly if rehearsal is prevented
P and P study findings and conclusion?
- recall of three letter trigrams
- 3 secs - 80% recall
- 9 secs - 20% recall
- 18 secs - <10% recall
- STM duration less than 18 seconds
Bahrick (1975) study overview?
- LTM duration
- recall names of high school yearbook and photo recognition
- longitudinal study
Bahrick findings and conclusion?
Photo recognition:
- 15 years - 90% accurate
- 48 years - 70% accurate
Free recall:
- 15 years - 60% accurate
- 48 years - 30% accurate
Conclusion - LTM duration very long possibly unlimited
Sensory Register coding?
Modality specific (encoded same way it’s received)
STM coding
Acoustically
LTM coding
Semantically
