memory Flashcards
coding
the format in which information is stored in various memory stores
process of converting information from one from to another
Baddely
coding in STM and LTM
1. acoustically similar words 2. dissimilar
3. semantically similar 3. dissimilar
- Immediate recall worse with acoustically similar words.
STM is acoustic
recall after 20 minutes worse with semantically dissimilar words. LTM is semantic
evaluation of study into coding in STM and LTM (Baddely)
artificial stimuli: word lists are meaningless material.
no personal meaning. when processing more meaning full info may use semantic coding even for STM tasks.
limited application - cant generalise.
capacity of short term memory (2 studies)
Jacobs
digit span: reads 4 digits and increases until participants cannot recall order correctly.
on average participants could repeat back 9.3 numbers and 7.3 letters in correct order immediately
Miller
observation of everyday practises. rule of 7
the span of STM is about 7 items but can be improved by chunking - grouping into meaningful units
evaluation of studies into capacity of STM
lacking validity: Jacobs study conducted a long time ago and lacked adequate control
miller overestimated capacity of STM. more research has concluded capacity was only about 4 chunks. lower end of the estimate is more appropriate.
study into the duration of LTM
Bahrick et al
- 400 participants from ohio aged 12-74
high school year books
photo recognition of 50 photos. 2 free recall test recalling names
48 years after recall of recognition was 70%
free recall was less good
15 years 60% accurate dropping to 30% after 48 years
study into the duration of STM
peterson and peterson
- tested 24 undergrads in 8 trials
- constant syllable and 3 digit no. to remember
students then asked to count back in 3 from that 3 digit no. untill told to stop preventing rehearsal.
stopped counting at different times
retention intervals
students recalled 80% syllable with 3 second intervals
18 seconds fell to 3%
STM without rehearsal is 18 - 30 seconds
evaluation of study into duration of STM (peterson)
meaningless stimuli: artificial material does not reflect real life so lacks external validity not totally irreverent as there are some applications. such as learning mobile numbers
the multi store memory model (MSM)
a representation of how memory works in terms of 3 stores
describes how info is transferred from one store to another and how it is forgotten if not rehearsed
MSM
sensory register
made up of multiple stores
- ionic: visual info
- echoic: auditory info
stimulus from the environment pass through
it has a store for each sense
very short duration less than 1 second. very high capacity
very little of what goes in goes to a further memory system unless you are paying attention to it.
MSM
short term memory store
- limited capacity of 5-9 items average of 7
- info coded acoustically
- duration of 30 seconds if not rehearsed
MSM
long term memory store
- a permanent memory store
- duration - potentially up to a lifetime
- capacity - potentially unlimited
- coding - semantic in terms of meaning
MSM
retrieval
when we want to recall materials stored in LTM it has to be transferred back to STM by a process called retrieval
MSM
maintenance rehearsal
- occurs when we repeat materials to ourselves we can keep info in STM as long as we can rehearse it
- if we rehearse long enough it passes to LTM
evaluation of multi store memory model
- support research: Baddeley mix up similar sounding words in STM and mixing up similar meaning words in LTM. STM - acoustic and LTM semantic. support stores as separate and independent
- more than 1 type of STM: amnesia suffers. STM memory of digits poor but improved when he read it himself. non verbal sounds. more than one type of STM
- artificial materials: research uses meaningless info and lacks external validity and can’t be generalised to every day life.
- oversimplifies LTM: LTM not unitary store, semantic, episodic. limitation
- MSM 1 type of rehearsal: maintenance and elaboration which is needed for long term link info to existing knowledge.
evaluation of the study into the duration of LTM
Bawick et al
high external validity: used real life meaningful memories when replicated with meaningless pictures recall falls.
confounding variables not controlled
participants might have looked at the book and rehearsed their memories between recalls.
types of long term memory
- episodic
- semantic
- procedural
procedural memory
stores knowledge of how to do things. learned motor skills we find them difficult to explain recall without conscious or deliberate effort. cannot actively recall them.
episodic memory
LTM memory store for personal event includes memories of when the event occurred - time stamped
includes several elements such as people, objects, places etc.
memory has to be retrieved consciously and with effort.
sematic memory
knowledge of the world includes facts knowledge of concepts memories are not time stamped less personal. knowledge we all share immense collection of material memories need to be recalled deliberately and with conscious effort.
evaluation of types of long term memory
clinical / case studies: amnesia (HW) difficulty recalling events bit semantic and procedural memory worked fine. supports.
neuroimaging : memory tasks while in PET scanners episodic in left and semantic in right prefrontal. physical reality. supporting validity
real life application: target kinds pf memories. episodic can be improved with mild cognitive therapy in patients.
problems with clinical case studies lack control and are hard to generalise
2 types of LTM : episodic and semantic are stored together and both are consciously controlled.
working memory model (WMM)
representation of short term memory.
see STM as a dynamic processor of different types of info using sub units coordinated by a central decision making system
visuo - spatial sketchpad (VSS)
Working memory model
stores visual and spatial info. capacity of 3-4 objects. subdivided into
- visual chache - stores visual data
- inner scribe records the arrangement of objects in the visual field.
what is the VSS subdivided into
visuo - spatial sketchpad
- visual chache - stores visual data
- inner scribe records the arrangement of objects in the visual field
central executive
WMM
- attentional process that monitors incoming data making decisions and allocates slave system to tasks
very limited processing capacity
episodic buffer
WMM
-added to the model by Baddeley
- temporary store for info, integrating visual, spatial and verbal info
- processed by other stores and maintaining same sequencing
capacity of 4 chunks
maintains sense of time sequencing recording events (episodes) that are happening
links the working memory to long term memory and wider cognitive processes
phonological loop
- deals with auditory info preserves the order in which info arrives
divided into - phonological store: stores words you hear
- articulatory process: allows maintenance rehearsal. capacity is 2 seconds of speech.