What does Oberauers model do that Cowans doesn’t?
- allows us to shine a spotlight on individual items in our spotlight
What is the Sternberg task? evidence for broad focus of attention
- 2 lists of colour coded wors
- vary the size of this between 1-3 items
- ask ppts to do Sternberg task- showed item of memoranda and ppt has to say which list it was in
- do 2 trials: second cue tells them which list they should be looking at
IV- Cue probe interval- how long items remain in broad focus of attention and activated LTM 100ms-2000ms - relevant and irrelevant list length (1-3 items)
- DV- RT to reject/accept items
- at short intervals set size of both lists (relevant and irrelevant) affects RT
- increase in RT from irrelevant set size 1-3 and relevant 1-3
- researchers interpret this to mean at short intervals you have all the items you need in your focus of attention so harder to choose
- at longer intervals we can remove the irrelevant list from our focus of attention
- when second probe indicates previoously irrelevant list is now relevant- ppts can respond accurately
- suggest broad focus of attention can flexibly shift from one set of stimuli to another
within 1-2s irrelevant list is removed from broad focus but remains active in LTM
- rejecting probes from irrelevant list- harder than new words
What is evidence for the narrow focus of attention?
- Sternber (1966) recognition paradigm show last item studied has a special status in WM
- Last item held accessible at higher rate than any other item from list- consistent with being held as the NFA
Object switching paradigms:
- ppts keep a running total of objects being presented
- on each trial- update previously updated count or switch count
What were results from object switching paradigms?
- DV in speed of response for each count
- switching from one count to another results in switch cost
- consistent with the narrow focus of attention shifting from one count to another
- repetitions result in faster response (repetition benefits)
What is a summary of the activation based models?
Compensate for some of the assumptions of the multicomponent model
- CE- homunculi
- separation of STM and LTM
- role of attention
- domain specificty
Developing research and model
What did Charles Spearmann say?
WM underlyes general intelligence (1925)
- performance on all cognitive tasks stems from a single factor ‘g’ (predicts how intelligent we are)
What have Hebb and Catell said on intelligence?
- moved away from one general factor of intelligence ‘g’
moved to: - crystallised intelligence
- fluid intelligence
What is crystallised intelligence?
- putting learned knowledge to use correctly
- vocabulary- know the rules of language
- knowing the rules of a board game or sport
- running a stats test on SPSS
- applying a technique you have practiced before
- any situation where you are applying previous knowledge and experience to a task
What is fluid intelligence?
- the ability to reason through and solve novel problems
- requires understanding of rules (crystallised knowledge) but adaptive understanding to create solutions to novel issues
- interpreting findings from a statistical test
- winning a board game
- how does this link to working memory?
How have people linked fluid intelligence to WM?
- common to all reasoning tasks is the fact that their solutions require the construction of new structural representations. Complexity of new structures is limited by the capacity of WM. (Oberauer, Wilhem and Sander)
- the crucial cognitive mechanism underlying fluid ability lies in storage capacity, which enables people to actively maintain distinct chunks of info and flexibly contruct task-relevant bindings among them (Chunderski, Taraday & Smolen)
What is Cowans magical number (WM)?
4
- only representations that are in the focus of attention are available to conscious awareness and report
- on average, the capacity limit of adults’ focus of attention is 4+/- 1 information elements
How can we observe the Cowans magic number?
set-size effect
- simple span task doesn’t require manipulation of information
- complex span task does require processing- see a rapid decline in ability to remember the information (the longer the set, the less likely you are to recall- set-size effect)
What are the 3 hypotheses for limits on WM?
- decay
- interference
- limited resource
Explain decay as a hypothesis for WM capacity
- representations in WM rapidly decay over time
- WM effectively works against decay
restoration mechanisms: - rehearsal: subvocally repeat memoranda to maintain them
- refreshing: think of memoranda to keep memory traces active
- passage of time alone doesn’t decay alone- time is correlated with processes that cause forgetting
How can we examine time-based decay?
- would expect the first memoranda would be the worst recalled and so on because if time was the only factor on memory because the first has been held onto for the longest etc…
- actually don’t see this- M1 has had more time to be rehearsed so is remembered better
- so forgetting may not be time but processes happening during this time
Explain interference as a hypothesis for WM forgetting
- WM is limited by mutual interference between representations
- pro/retroactive
types of interference:
1. confusion- confused the position of one item for another
2. superposition- orientation gets confused, ppts report combined of old and distractor, more dissimilar decrease performance
3. overwriting- phonologically similar decrease performance as they start to merge
What is a superposition experiment?
- have to remeber orientation of a shape
- distractor image becomes superimposed over the representation held in WM
- representations combine- ppts report an average of both of the results
What is hypothesis 3 on resource that limits WM?
working memory capacity is determined by a limited quantity of resource that enables holding representations available
What is an example of how the resource is allocated to representations?
discrete: allocation of resource to a limited number of items, with no information stored about additional items
continuous: equal spread of resource among all items, with fewer resurce per item for larger arrays
What is meant by resource models? What is the egg carton metaphor?
- a resource is a limited quantity that enables a cognitive function or process, such that its probably of success increases the larger the amount of resource assigned to it
egg-carton: DESCRIBING 1. SLOT MODELS
- can’t put half an egg in a unity
- resources are distributed in discrete units (defining the number of items one can store)
- quality of the retained representations is not perfect but sufficiently high
- flexible resource models:
- resources are distributed flexibly. Allowing for: a) a small number of high quality objects or b) a high number of low quality objects
Who is WM capacity greater in?
greater in:
- older children than younger children
- younger adults than older adults
- healthy people than people with frontal lobe damage
- some younger adults than other younger adults
Why is it important to see what makes a good WM?
WM correlates with complex cognitive activities:
- reading comprehension, reasoning and problem solving
Predicts:
- cognitive development and individual differences in intellectual abilities
How do we measure variation in WM?
letter updating task- always remember the last 3 letters of a long list, increase list to make more difficult
What other processes may be involved in variation in WM tasks?
- attention- have to shift our attention from one element to another
- may have to inhibit our responses- ocognitive inhibition
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Social attention23
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Culture and attention16
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fMRI and cognition21
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Models18
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Computational models of speech prouction33
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Computational models of language comprehension24
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Reading and dyslexia40
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Animal cognition:comparative models of working memory35
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Animal cognition part 2- insight related cognition21
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Multisensory integration26
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Multisensory integration 2 (watch lecture back)27
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Working memory 1: Theories and models34
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Working memory- capacity35
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Working memory 3- training effects and mechanisms26
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Cognitive control: inhibition and the race model of stopping45
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Skill, habit and expertise33
