Slides in this set
THE NATURE OF MEMORY STM,
LTM AND DURATION
Memory the process by which we retain
information about events that happened in the
STM present or immediate past
LTM memory for events that have happened
in the more distant past…read more
THE NATURE OF MEMORY
Duration of Short Term Memory
Duration how long a memory lasts
before it is no longer available
STMs don't last very long
Most people keep information in their
STM by rehearsing it keeps the
Result of verbal rehearsal is that
short-term memories are held in STM
store and eventually become long-
NATURE OF MEMORY
Studies of duration of STM
Peterson and Peterson (1959) studied the duration of STM.
Enlisted 24 students.
Experimenter said a consonant syllable to the ppt followed by a 3-
Consonant syllable was selected to have no meaning.
Immediately after hearing syllable and number, ppt had to count
backwards from this number in 3s until told to stop.
Then the ppt was asked to recall the consonant syllable.
Counting backwards was to stop the ppts rehearsing the syllable.
The retention interval was different each time: 3,6,9,15 or 18
Ppts remembered about 90% when there was only a 3 second
interval and about 2% when there was an 18-second interval
Suggests that when rehearsal is prevented, STM last about 20
seconds at the most.…read more
NATURE OF MEMORY
Duration of LTM
Psychologists have investigated duration of LTM and
demonstrated that some memories are very long
Shepard (1967) showed ppts 612 memorable pics,
one at a time.
1 hour later shown these pics among a set of others
and showed almost perfect recognition
4months later still able to recognise 50% of the
Bahrick et al (1975) conducted a more `real life'
Demonstrated the considerable duration of LTM by
asking people of various ages to put names to faces
from their high school year book. 48 years on, people
were about 70% accurate…read more