Psychology and the Brain: Week 6
Working memory – a History
- Working memory
- Long-term memory
- memory is not unitary
William James (1890):
- first conceptualised memory according to his own observations
- defined it in terms of two stores primary and secondary memory
Primary memory/working memory:
- the kind of memory that is consciously available to people as it involved the
thoughts, they kept in their minds
- Information available to consciousness
- Retrieval effortless
Secondary memory:
- we are not always aware of and thus need to work harder to retrieve
- Long-term storage, not consciously available unless cognitively activated
- Retrieval effortful
- As James did not conduct any experiments on this it was unclear what the capacity
of these stores would be and how we would access them
Defining working memory: George Miller (1956)
- Some clarification regarding the capacity of the primary memory store was provided
by the American psychologist George Miller
- use of a digit span task
- when looking at how much we can retain in this temporary store he found out that
the magic number is 7
- on average we can hold approximately 7 numbers plus or minus 2 in working
memory
- Though note the term ‘item’ is not necessarily fixed as individual items can be
chunked which is what we commonly do in order to remember phone numbers
- e.g., 020 7848 3490
Modal Model of memory –
- findings led to the formulation of the modal model of memory formulated by
Atkinson and Shiffrin
- sensory input is stored in sensory stores was thought to be transferred to a short-
term memory store
- a person would have to consciously use a strategy such as rehearsal to translate a
memory into a permanent one in a long-term memory store
- otherwise the memory would be displaced or in other words forgotten
- this permanent memory would then have to be fed back to the short-term memory
store in order to be recalled
, Psychology and the Brain: Week 6
- we now know that this is not how memory works
- short term memory does not only have one store
- memory does not operate in this sequential manner
Shallice & Warrington (1970):
- tested patient K.F.
- had a severe short-term memory impairment
- they could not do the digit span task or keep a short list of words in memory
- however, their long-term memory was intact
This was evidence in favour of a model in which:
- short term and long-term memory do not operate in a serial manner as the modal
model of memory suggests
- but rather independently
Dual task paradigm:
- suggests that short term memory does not just contain a single store but rather has
different stores for different types of information
- participants complete two tasks simultaneously
Baddeley & Hitch (1974):
- people were asked to remember a string of digits
- whilst completing a simple spatial reasoning task
- decide whether or not a statement regarding the positioning of letters is correct
- e.g ‘CG’ – ‘G is after C – true or false?
- found whilst participants could perform the task accurately regardless of how many
digits, they were asked to keep in mind
- the task became more effortful - it took longer as the number of digits increased
- indicates it’s unlikely that the same resources that are being used to store these
digits are also being used to complete the reasoning task
- if this was the case the errors would increase as a function of load
Working memory – a History
- Working memory
- Long-term memory
- memory is not unitary
William James (1890):
- first conceptualised memory according to his own observations
- defined it in terms of two stores primary and secondary memory
Primary memory/working memory:
- the kind of memory that is consciously available to people as it involved the
thoughts, they kept in their minds
- Information available to consciousness
- Retrieval effortless
Secondary memory:
- we are not always aware of and thus need to work harder to retrieve
- Long-term storage, not consciously available unless cognitively activated
- Retrieval effortful
- As James did not conduct any experiments on this it was unclear what the capacity
of these stores would be and how we would access them
Defining working memory: George Miller (1956)
- Some clarification regarding the capacity of the primary memory store was provided
by the American psychologist George Miller
- use of a digit span task
- when looking at how much we can retain in this temporary store he found out that
the magic number is 7
- on average we can hold approximately 7 numbers plus or minus 2 in working
memory
- Though note the term ‘item’ is not necessarily fixed as individual items can be
chunked which is what we commonly do in order to remember phone numbers
- e.g., 020 7848 3490
Modal Model of memory –
- findings led to the formulation of the modal model of memory formulated by
Atkinson and Shiffrin
- sensory input is stored in sensory stores was thought to be transferred to a short-
term memory store
- a person would have to consciously use a strategy such as rehearsal to translate a
memory into a permanent one in a long-term memory store
- otherwise the memory would be displaced or in other words forgotten
- this permanent memory would then have to be fed back to the short-term memory
store in order to be recalled
, Psychology and the Brain: Week 6
- we now know that this is not how memory works
- short term memory does not only have one store
- memory does not operate in this sequential manner
Shallice & Warrington (1970):
- tested patient K.F.
- had a severe short-term memory impairment
- they could not do the digit span task or keep a short list of words in memory
- however, their long-term memory was intact
This was evidence in favour of a model in which:
- short term and long-term memory do not operate in a serial manner as the modal
model of memory suggests
- but rather independently
Dual task paradigm:
- suggests that short term memory does not just contain a single store but rather has
different stores for different types of information
- participants complete two tasks simultaneously
Baddeley & Hitch (1974):
- people were asked to remember a string of digits
- whilst completing a simple spatial reasoning task
- decide whether or not a statement regarding the positioning of letters is correct
- e.g ‘CG’ – ‘G is after C – true or false?
- found whilst participants could perform the task accurately regardless of how many
digits, they were asked to keep in mind
- the task became more effortful - it took longer as the number of digits increased
- indicates it’s unlikely that the same resources that are being used to store these
digits are also being used to complete the reasoning task
- if this was the case the errors would increase as a function of load
