Memory 2 Flashcards
what does STM do?
describes ability to hold items in memory for few seconds
what is the capacity of STM?
- 7+/-2 items
- chunks of 4
what is the serial-position effect?
the tendency of a person to recall the first and last items in a series
what is primacy interpreted down to being?
rehearsal
define the recency effect
the tendency to remember the most recent information
what is recency interpreted as?
the capacity of short term store
this is because latest information presented is stored into stm
what does the serial position curve plot?
likelihood of remembering
explain the serial position curve in free recall
- helps us understand properties of STM
- items recalled first on list are often well remembered
- items recalled last on list are well remembered
- there is a chunk in the middle where performance of recall falls to 50%
- primacy effect - successful recall of start of list
- recency effect - successful recall of end of list
reason we can do well on last items on list is because information is still in head, automatically placed in Short Term Store
- beginning of curve = primacy effect
- flat mid-part of curve = transfer to long term store
- end of curve = recency effect
Who are associated with the traditional view of STS and LTS
Atkinson & Shiffrin (1968)
Outline the Multi-Store Model of Memory
(Atkinson & Shiffrin, 1968)
- shows how memory uses rehearsal to transfer from STM to LTM
- regarded rehearsal as holding information in STM before transferring it to LTM
identify reasons the serial position curve may be controversial
- evidence that rehearsal is neither necessary nor sufficient
- rehearsal is not necessary as in serial position curve, curve is never at 0 even for unrehearsed items
- suggesting that rehearsal is not needed to retrieve items
- rehearsal is not sufficient as it does not always work (rehearsal does not always get information into LTM)
- this is shown through a distinction between two types of rehearsal
- maintenance vs elaborative
what is maintenance rehearsal?
rehearsing information to keep it in short-term memory
(holding information)
what is elaborative rehearsal?
- making connections and elaborating on the meaning of items
- it is not enough to hold information in memory
- you need to make links, get meaning, make associations to transfer information to long-term memory
where does evidence come from to show that STM and LTM are separate stores?
brain damage patients provide neurological evidence
Explain how Baddeley & Hitch (1974) research short-term memory being a unitary store?
- ‘if short-term memory is completely full, what is it that you cannot do?’
to investigate this:
- designed several tasks designed to simulate the absence of short-term memory
- ppts are asked to complete a task (remember 7 digits)
- task takes up one component of a system, experimenters see what this prevents you doing
- this was done using a dual-task paradigm to fill up short-term memory
FINDINGS:
- STM is impaired but not devastated
- when asked to hold more digits in first task, secondary tasks became harder but not impossible to complete
- Reasoning speed depended on the memory load (just took longer to complete tasks)
give examples of the task used in Baddeley’s study
- classic digit span task
ppts given list of digits to remember
this fills up STM
as ppts did this, they were asked to:
- complete reading task
extract meaning from reading, answer T or F questions to show understanding
- make semantic judgement
think about meaning, A comes before B = AB - learn a list
requires long-term memory, learning long list of items - understand prose
reading chunks of prose, understanding what the contents is
What model did Baddeley & Hitch (1974) propose to explain what short-term memory does?
The Multicomponent Model of the STS
aka Working Memory Model
Explain the multicomponent model of the short-term store
- model suggests that short-term memory must have different components
- short-term memory split into 3 components
- components include:
central executive
phonological loop
visuospatial sketchpad
explain the role of the central executive component of the working memory model
- control flow of information
- directs information to either visuospatial sketchpad or phonological loop
explain the role of the visuospatial sketchpad
temporarily hold visual and spatial information
what did Brooks (1967) notice about memory, in terms of memory capacity and visual versus verbal information?
it makes a difference how much information is stored depending on if given in a visual or verbal way, regardless if information given is the same
outline Brooks (1967) classic task
visuospatial, remembering words, matrix/grid
Visuospatial Sketchpad = a workspace where an image can be stored and manipulated to guide behaviour
- ppts asked to imagine a 4x4 grid
- subjects learn sequence of sentences
- sequences either contained spatial related words (in the next square to the RIGHT, put a 2) or non-spatial related words (in the next square to the QUICK, put a 2)
- If you have a spatial context to remember words, you can remember a words using the visuospatial encoding
FINDINGS:
- providing ppts with spatial help really helped capacity of STM
- Short-term span for meaningful spatial symbols = 8
- Short-term span for same meaning but no spatial reference points = 6
Outline Brooks (1968) dual task interference study
idea is that if one part of STM is filled up, this should make it difficult to complete other tasks
- conducted two tasks; verbal and spatial task
SPATIAL TASK:
- imagine an F
- ppts told to image a dot starting bottom left of F
- ppts asked to go round F and for each vertex, determine if point is an outside point
VERBAL TASK
- Is each word a concrete noun
- Asking ppts if words in a sentence are concrete nouns or not
Ppts were asked to respond in 2 different ways:
verbal and spatial output
verbal output = ppts respond yes or no
spatial output = ppts had to point to Y or N to indicate response
Outline Brooks (1968) dual task interference study findings
- when completing verbal task, output does not matter as task is still performed efficiently
- in the spatial task, it took longer to produce a spatial output from ppts
- performance = impaired if spatial output was required for a spatial task
