Specification:
Coding, capacity, and duration of STM and LTM
Duration = how long information can be stored for
Capacity = how much info can be stored
Encoding = the format a memory is stored in. 3 ways to format a memory:
visually, acoustically and semantically. The process of taking in information into
the brain to be stored is known as encoding.
Coding
1 Baddeley - Aim: To investigate the encoding of STM and LTM. Procedure:
Participants were given four sets of words to recall in order. Set 1: Words
acoustically similar. Set 2: Words not acoustically similar. Set 3: Words
semantically similar. Set 4: Words not semantically similar. Recorded how
many mistakes were made in recalling the sets of words. For the STM task they
had to recall them immediately following presentation and for the LTM task
they had to be recalled following a longer time interval.
STM Findings: Immediate recall was worse with acoustically similar words. STM
is encoded mainly acoustically.
LTM Findings: recall after 20 minutes was worse with semantically similar
words, LTM is encoded mainly semantically
(The acoustic similarity of the words confuse the STM when it is trying to
encode information which shows that the STM does store information
acoustically. LTM, since it encodes information semantically, it gets confused
, with words that have the same meaning, thereby finding it difficult to encode
all the words and resulting in poor recalling).
Ao3:
One strength of Baddeley’s study was it identified a clear difference between 2
memory stores. It was an important step in our understanding of the memory
system which led to the multi store model.
Limitation of Baddeley’s study is he used artificial stimuli rather than
meaningful material, word lists had no personal meaning to participants.
Suggests findings have limited application.
Capacity
LTM: The potential capacity of LTM is unlimited. Information may be lost due
to decay and interference, but such losses doesn’t happen due to limitation of
capacity.
STM: Miller and Jacobs tell us the capacity of STM is limited.
1 Miller found the span of STM is 7 +/- 2 (millers magic number) But can be
improved via chunking.
2 Jacobs (1887) - Aim: To investigate the capacity of short-term memory (STM).
Procedure: Read lists of numbers – immediate recall. Results: Jacobs found a
difference between capacity for numbers and for letters. On average
participants could recall 9 numbers but only 7 letters.
What to avoid when creating memory tasks based on capacity:
Words - has meaning so can be recalled as a whole.
Acronyms - have meaning so can also be recalled as a whole.
Multiple repetitions - reduces cognitive demand.
Coding, capacity, and duration of STM and LTM
Duration = how long information can be stored for
Capacity = how much info can be stored
Encoding = the format a memory is stored in. 3 ways to format a memory:
visually, acoustically and semantically. The process of taking in information into
the brain to be stored is known as encoding.
Coding
1 Baddeley - Aim: To investigate the encoding of STM and LTM. Procedure:
Participants were given four sets of words to recall in order. Set 1: Words
acoustically similar. Set 2: Words not acoustically similar. Set 3: Words
semantically similar. Set 4: Words not semantically similar. Recorded how
many mistakes were made in recalling the sets of words. For the STM task they
had to recall them immediately following presentation and for the LTM task
they had to be recalled following a longer time interval.
STM Findings: Immediate recall was worse with acoustically similar words. STM
is encoded mainly acoustically.
LTM Findings: recall after 20 minutes was worse with semantically similar
words, LTM is encoded mainly semantically
(The acoustic similarity of the words confuse the STM when it is trying to
encode information which shows that the STM does store information
acoustically. LTM, since it encodes information semantically, it gets confused
, with words that have the same meaning, thereby finding it difficult to encode
all the words and resulting in poor recalling).
Ao3:
One strength of Baddeley’s study was it identified a clear difference between 2
memory stores. It was an important step in our understanding of the memory
system which led to the multi store model.
Limitation of Baddeley’s study is he used artificial stimuli rather than
meaningful material, word lists had no personal meaning to participants.
Suggests findings have limited application.
Capacity
LTM: The potential capacity of LTM is unlimited. Information may be lost due
to decay and interference, but such losses doesn’t happen due to limitation of
capacity.
STM: Miller and Jacobs tell us the capacity of STM is limited.
1 Miller found the span of STM is 7 +/- 2 (millers magic number) But can be
improved via chunking.
2 Jacobs (1887) - Aim: To investigate the capacity of short-term memory (STM).
Procedure: Read lists of numbers – immediate recall. Results: Jacobs found a
difference between capacity for numbers and for letters. On average
participants could recall 9 numbers but only 7 letters.
What to avoid when creating memory tasks based on capacity:
Words - has meaning so can be recalled as a whole.
Acronyms - have meaning so can also be recalled as a whole.
Multiple repetitions - reduces cognitive demand.
