2 - memory Flashcards
what is capacity in relation to memory
how much information can be held in a memory store
what is duration in relation to memory
the length of time information can be held in a memory store
what is encoding in relation to memory
the form in which the info is ‘written’ into memory stores e.g. acoustic
what did Jacobs (1887) test?
capacity of memory
digit span test
443 female samples age 8-19 from london school
students had an average span of 7.3 letters and 9.3 numbers
what did Miller 1956 say
he agreed with Jacobs’ research but said it was chunks of info rather than individual numbers
said the 7+-2
AO3 of capacity studies
- findings of Jacobs supports Miller’s claim
- memory improves with age up to a certain point
- didn’t take into account other factors
- size of chunk is not specific so its hard to know how big capacity is
what did Peterson and Peterson find out about duration
- the longer the interval, the less accurate the recall
- in a 3 second gap, 90% were recalled correctly
- in a 18 second gap, 2% were recalled correctly
concluded that short term memory had a limit of about 18 seconds
AO3 of duration studies - letter recall
- low level of ecological validity
- lab so is artificial
- no consequences
- unable to apply results to everyday examples e.g. remember phone number
what are the 3 types of encoding
visual
acoustic
semantic
who said that short term memory is primarily acoustic?
Baddely
what did Brandimote find?
lalala
participants used visual coding for STM if they were given a visual task and were prevented from doing any verbal rehearsals- had to say la la la before recalling
what is said about capacity for long term memory?
we have an unlimited capacity and no research has been carried out
What did Bahrick find out about LTM duration
we have unlimited duration
Aims of Bahrick’s study
Investigate the duration of Long term memory
Method of Bahrick’s study
- 400 people of various ages 17-74 were tested on their memory of classmates
- 50 photos shown and pp’s had to recall all the names they could
- then free call - name as many without a prompt
Findings of Bahrick’s research
with the pictures
within 15 years - 90% accurate
after 48 years - 70%
free recall
within 15 years - 60% accurate
after 48 years - 30%
Conclusion of Bahrick’s study
LTM has a seemingly unlimited duration
AO3 points for Bahrick’s study
field study - high ecological validity
validity - don’t know if people looked at books, kept in touch etc.
what did Baddely find out about coding in long term memory
immediately and later recalling sematic or acoustic words
immediate recall - problems with acoustically similar words
recalling later - problems with semantics
due to similarity, types of memory were confused and didn’t perform well
AO3 of Baddely’s research into encoding in LTM
limitation
P - LTM is normally semantic but not always
E - Frost showed that LTM recall was related to visual as well and Nelson + Rothbart found evidence of acoustic
E - can vary on circumstance
what is the capacity, duration, and coding of the sensory register
capacity - large
duration - short half a second
coding - all senses
who came up with the multi store model?
Atkinson and Shiffrin (1968)
strengths of the multi store model
- all results and experiments from LTM and STM for example Baddely
- influenced many other models such as the working memory model
- brain scanning evidence supports that there is a difference between STM and LTM
explain what happened with HM
- had his hippocampus removed
- he couldn’t form new LTM’s but could remember things from before
- this supports MSM as he had a working STM and could retrieve LTM
- showing how they are separate
limitations of the multi store model
- over simplifies memory - working memory model shows that memory is divided even further
- Logie pointed out that STM relies on LTM
describe the multi store model
- senses enter the sensory memory
- sensory memory is transferred to short term memory
- rehearsal of STM keeps in in STM or takes it to LTM
- retrieval of LTM takes memory to STM
what is the main difference between the working memory model and the multi store model?
WMM focusses in more detail on the workings of short term memory
who came up with the working memory model
Baddeley and Hitch
what does the central executive do?
- direct attention to particular task
- determines how the brain’s ‘resources’ are allocated tasks
- ‘resources’ are the 3 sub systems
- limited capacity
- data arrives from the senses of LTM
what is the phonological loop?
- limited capacity
- deals with auditory info and the order of information
split into 2 stores
1 - phonological store - words heard
2 - articulatory process - words heard or seen. silently repeated
what is the visuospatial sketchpad?
- used when planning a spatical task e.g. counting windows on your house
- visual and/or spatical stored temporarily here
- capacity is around 3-4 objects
what is the difference between visual and spatical
visual - things you see
spatical - physical relationship between things
what did Logie suggest about visuospatial sketchpad?
it could be split into two
1 - visual cache which stores info of visual items e.g. form and colour
2 - inner scribe - stores arrangement of objects in visual field
what is the episodic buffer?
- extra storage with limited capacity of 4 chunks
- integrates info from all other stores and LTM
give strengths/support of the Working Memory Model
1) dual task performance by Baddeley shows that there is more than one component to memory
(visual + visual) or (visual + auditory)
2) K.F by Shallice and Warrington - motorbike crash
short term forgetting of auditory info was much greater than visual stimuli
auditory problems were limited to verbal materials such as letters and digits
brain was restricted to just the phonological loop
limitations of the Working memory model
1) individual case studies should be used with caution as evidence as the trauma of the brain injury may have altered other aspects of behaviour such as concentration and attention
2) too vague still about central executive
- there are probably more components
- the central executive is the most important aspect but the least understood so reduces the whole credibility of the model - Baddeley
3) LTM is still to simplified like the MSM
how long until something is transferred to LTM?
30 seconds
what is a declarative memory?
explicit memories which can be inspected and recalled consciously