Describe research into the components of memory (short term, long term and sensory register).
Refer to capacity, encoding and duration in your answer.
Atkinson and Shiffrin proposed the multi-store model, which shows how information flows through
the processes of memory. It is made up of three components: sensory memory, short term memory
and long term memory. Sensory memory, sometimes referred to as sensory register, is a temporary
storage system where sensory information enters the memory via our senses. Short term memory is
your memory for the present or immediate past. It stores memory for short periods of time. Long
term memory functions in a more complex way compared to STM and appears to hold our memory
for longer than STM.
The sensory register is constantly receiving information and, unless we pay attention to it, the
information will decay. The capacity of the SR is high as the information it receives is in a raw and
highly detailed format. This is shown by Sperling’s experiment (1960). Sperling flashed a 3x4 letter
grid on a screen for participants to look at. However, they were only shown for one twelfth of a
second, therefore they would have to rely on their sensory register to recall the letters. Because the
information would decay quickly, the participants heard a tone that indicated the row that had to be
recalled. The results of this experiment indicated that the iconic memory has a large capacity.
Information is stored in an unprocessed form and encoded in separate stores for each of the senses:
echoic (auditory), iconic (visual), haptic (tactic), gustatory (taste) and olfactory (smell). Crowder
(1933) discovered that the iconic store hold information for a few milliseconds but the echoic store
holds information for 2-3 seconds. This suggests that there are separate sensory stores as well as
varying durations. The duration of the sensory register varies for each sensory store. Information
stays in the sensory register for a very brief time. Iconic information stays for less than a second,
while the auditory information lasts longer, with a duration 2-4 seconds. Walsh and Thompson (1978)
suggested that the iconic store has an average duration of 500 milliseconds but this may decrease as
you get older. Therefore, duration in the SR is limited and dependant on age.
Short term memory is a temporary memory store that holds information for a short period of time.
The capacity of STM can be assessed using digit span. Jacobs (1887) found that the average span for
digits was 9.3 items and 7.3 for letters. Miller’s Magic Number provided further insight into this.
Participants were given a list of random digit strings (from a row of 3 to 10 digits) and asked to recall
them in the correct order. Conclusively, his findings suggested that the average IDS is 7 ± 9.
The duration of STM is relatively short and anything we need to remember for longer should be
transferred to LTM. Peterson and Peterson (1959) looked into how long STM lasts when rehearsal is
prevented. The participants were shown a consonant trigram (e.g. FKY) and then asked to count back
in 3s from a specified number to stop them focusing on the trigram. After intervals of 3, 6, 9, 12, 15
and 18 seconds they were asked to recall them. The procedure was repeated many times using
different trigrams. The evidence showed that 80% of the trigrams were recalled correctly after the 3
second interval and, progressively, less trigrams were recalled as the time intervals increased.
Therefore, the duration of STM is approximately 18 seconds when not being rehearsed.
In STM, information is encoded visually (visualising the object or word), acoustically (saying the word
aloud) or semantically (thinking about the meaning of the word). Evidence for encoding in STM
comes from substitution errors. This occurs when a person confuses one item for another (e.g. letters
that sound alike). If people confuse letters that sound alike, this would mean acoustic coding is being
used. If, however, people confuse letters that look alike, we could assume that visual coding is being
used. Baddeley’s experiment (1966) explored the effects of acoustic and semantic encoding in STM
and LTM. Participants were shown and asked to recall in serial order a list of five words taken from
the following categories: acoustically similar words (e.g. man, mad, map), acoustically dissimilar
words (e.g. pen, day, like), semantically similar words (e.g. big, huge, large) and semantically
dissimilar words (e.g. hot, old, late). The results showed that words with similar sounds were harder
to recall using STM than words with dissimilar sounds. They also showed that the meaning of the
words only had a slight negative effect on STM. The experiment therefore concluded that STM relies
heavily on acoustic coding.
Refer to capacity, encoding and duration in your answer.
Atkinson and Shiffrin proposed the multi-store model, which shows how information flows through
the processes of memory. It is made up of three components: sensory memory, short term memory
and long term memory. Sensory memory, sometimes referred to as sensory register, is a temporary
storage system where sensory information enters the memory via our senses. Short term memory is
your memory for the present or immediate past. It stores memory for short periods of time. Long
term memory functions in a more complex way compared to STM and appears to hold our memory
for longer than STM.
The sensory register is constantly receiving information and, unless we pay attention to it, the
information will decay. The capacity of the SR is high as the information it receives is in a raw and
highly detailed format. This is shown by Sperling’s experiment (1960). Sperling flashed a 3x4 letter
grid on a screen for participants to look at. However, they were only shown for one twelfth of a
second, therefore they would have to rely on their sensory register to recall the letters. Because the
information would decay quickly, the participants heard a tone that indicated the row that had to be
recalled. The results of this experiment indicated that the iconic memory has a large capacity.
Information is stored in an unprocessed form and encoded in separate stores for each of the senses:
echoic (auditory), iconic (visual), haptic (tactic), gustatory (taste) and olfactory (smell). Crowder
(1933) discovered that the iconic store hold information for a few milliseconds but the echoic store
holds information for 2-3 seconds. This suggests that there are separate sensory stores as well as
varying durations. The duration of the sensory register varies for each sensory store. Information
stays in the sensory register for a very brief time. Iconic information stays for less than a second,
while the auditory information lasts longer, with a duration 2-4 seconds. Walsh and Thompson (1978)
suggested that the iconic store has an average duration of 500 milliseconds but this may decrease as
you get older. Therefore, duration in the SR is limited and dependant on age.
Short term memory is a temporary memory store that holds information for a short period of time.
The capacity of STM can be assessed using digit span. Jacobs (1887) found that the average span for
digits was 9.3 items and 7.3 for letters. Miller’s Magic Number provided further insight into this.
Participants were given a list of random digit strings (from a row of 3 to 10 digits) and asked to recall
them in the correct order. Conclusively, his findings suggested that the average IDS is 7 ± 9.
The duration of STM is relatively short and anything we need to remember for longer should be
transferred to LTM. Peterson and Peterson (1959) looked into how long STM lasts when rehearsal is
prevented. The participants were shown a consonant trigram (e.g. FKY) and then asked to count back
in 3s from a specified number to stop them focusing on the trigram. After intervals of 3, 6, 9, 12, 15
and 18 seconds they were asked to recall them. The procedure was repeated many times using
different trigrams. The evidence showed that 80% of the trigrams were recalled correctly after the 3
second interval and, progressively, less trigrams were recalled as the time intervals increased.
Therefore, the duration of STM is approximately 18 seconds when not being rehearsed.
In STM, information is encoded visually (visualising the object or word), acoustically (saying the word
aloud) or semantically (thinking about the meaning of the word). Evidence for encoding in STM
comes from substitution errors. This occurs when a person confuses one item for another (e.g. letters
that sound alike). If people confuse letters that sound alike, this would mean acoustic coding is being
used. If, however, people confuse letters that look alike, we could assume that visual coding is being
used. Baddeley’s experiment (1966) explored the effects of acoustic and semantic encoding in STM
and LTM. Participants were shown and asked to recall in serial order a list of five words taken from
the following categories: acoustically similar words (e.g. man, mad, map), acoustically dissimilar
words (e.g. pen, day, like), semantically similar words (e.g. big, huge, large) and semantically
dissimilar words (e.g. hot, old, late). The results showed that words with similar sounds were harder
to recall using STM than words with dissimilar sounds. They also showed that the meaning of the
words only had a slight negative effect on STM. The experiment therefore concluded that STM relies
heavily on acoustic coding.
