WM & executive functions Flashcards
Understand the 3 main assumptions of the “Standard Model” of WM (Nairne)
Based on 3 assumptions
1. activation
- Short-term memory storage is based on the activation of memory representations
- Active representations are easily accessible
- all retrieval is about activation and only relies on activation
- Activation is fragile
- Information is lost due to decay
- Decay is a direct function of time and hence a constant “force”
- Decay is adaptive, no longer needed info is automatically removed - Rehearsal counteracts decay
Refreshes activation
Cite evidence supporting the standard model
Early evidence for a time-based rehearsal-plus-decay model was strong
- Articulation rate effects (e.g., word length). Better memory for short vs. long words (e.g., ball, plum > tricycle, pineapple). Shorter words allowed more rehearsal = less effect of decay
- Articulatory suppression effects (“the, the, the”). Memory performance declines. prevents rehearsal = more effect of decay
Blocks the phonological loo
Be able to critique the standard model, using empirical evidence
problems with activation
PROBLEMS W ACTIVATION
- Standard model assumes that activation determines the accessibility
- does not specify a cue-dependent retrieval process
- Sometimes activated information is not easily accessible:
“Release” from proactive interference (Wickens, 1970)
- given different lists w diff cues then given different lists w the same cues
- Demonstrates that in cue overload as even the most recently activated list could not be remembered by the cue
- performance declines and there is proactive interference even in the most recently activated word list
Be able to critique the standard model, using empirical evidence
problems with rehearsal
- Decay is assumed to be fixed
- so remembering hinges on one’s ability to actively maintain information in the face of constant decay = rehearsal
- so most variability in memory span should be directly attributable to rehearsal
- Recall rate can differ despite equivalent articulation (= rehearsal) rate
Hulme et al. (1991)
- Words and nonwords matched for articulation rate
- e.g. holiday vs. dalihoy
- Three different lengths: One, three and five-syllable items
- Word advantage cannot be attributed to rehearsal rates in varying word lengths and difficulty
- the words were consistently remembered better indicating better retrieval cues available for words (cue-dependence)
Cite a piece of evidence showing that time does not directly cause forgetting
Problems with decay
- time does not cause forgetting, in this model decay is fixed with time
- its cognitive load of the task and interference during task
- and the extent of forgetting depends more on the activities that occur during the retention interval than its duration
Lewandowsky et al., 2008
- Articulatory suppression: “1, 2, 3, 4, 5, 6” causes more forgetting than “1, 1, 1, 1, 1, 1” (more distractors = more interference). higher cognitive load and competition for resources
- No cognitive activity between study and test (rest, sleep)
- little forgetting even over long periods of time
complex span task (Oberauer 2012)
- they tested: if the notion of decay is correct, more processing time (of distractor task) must lead to more forgetting
- 5 to be remembered words with 3 distractor words in between each and then a distractor task
- one in a shorter amount of time
- one in a longer amount of time in theory should be more decay in this condition
They found that time does not cause forgetting
Understand the main assumption of the attentional control model of WM (engle 1999, 2002) (including supporting evidence)
Similar to Baddley but different:
- made of three parts short/long term memory, central executive and procedures for maintaining activation
- STM is inside/a part of the same memory system as LTM
- WM capacity is defined as the “ability to control attention to maintain information in an active, quickly retrievable state” therefore also about its abilities to control and focus
Greater WM capacity should also mean greater ability to use attention to avoid distraction
Colflesh & Conway, 2007
- when testing the cocktail party & the own-name effect they found High WM-span people less likely than low-span people to notice their own name in “unattended ear”
- unless instructed to, then the pattern reverses
Kane, Bleckley, Conway, & Engle (2001)
- Examined whether individual differences in WM capacity are related to individual differences in attentional control
- Individuals classified as having high or low WM span
- Tested attentional control using a prosaccade/antisaccade task (saccade = eye movement)
- Found that low-span participants were slower to identify targets in antisaccade conditions eg low span found it more difficult to control attention and resist looking at the cue
- prosaccade task no diff in groups
- The better you are able to ignore distracting information, the less irrelevant information enters your WM and interferes with the important information in WM.
Understand hierarchical model(s) of WM (including supporting evidence)
- first developed by (Cowan,1988, 1999) then (Oberauer, 2002, 2009) built on them
- focuses on hierarchical levels of activation
- 3 components
(Cowan,1988, 1999)
LTM
- lots if interconnections
- everything we know
- the largest encompassing box
Activated memory WM
- not in consciousness but they’re activated
- eg info in your brain ready for the lecture topic
focus of attention WM
- highly activated info in your conscious memory
- 4 items
(Oberauer, 2002, 2009)
Oberauer then argued you can only hold 1 item in your focus of attention
- similar to a cognitive bottleneck
Garavan (1998) displayed this
- Task: Maintain two counts of squares and triangles,
press key when updated
- WM updating 300-500 ms quicker if same count is
updated (i.e., 1 triangle…2 triangles) therefore only one count can be manipulated in the focus-of attention, the other maintained outside—moving FoA takes time
the model is made up of connections and nodes overall 6 parts:
- executive control
- all the nodes are LTM
- activated LTM
- Direct region of access
- Cognitive coordinate system
- the focus of attention
- selected item for processing
LTM
- An associative network of representations that activate each other automatically along their association
- LTM as basis for WM easily explains effects of cue-dependence that trouble the “standard model”
Activated LTM
* Active set of LTM representations , Allows for quick access to relevant information (task-, goal-dependent)
- the activated memory is the large circle: holds 3 to 4 items: immediately accessible
Direct-Access Region
* Retrieval into DA-region makes a small number of elements immediately accessible
* Contains what you are “holding in STM”
* Forgetting from WM is not due to decay but interference and resulting failure to access information
cognitive coordinate system
- you can arrange and integrate items into your DA region in a flexible manner
Focus-of-Attention
* Selects a single representation for cognitive action
* Can select only from the DA-region
what is executive control and what are its processes
Executive control performs a bunch of important tasks related to:
the central executive functions are: according to mikaye
- Mental set (task, attention) shifting e.g., plus/minus task: 5+3=… 7+2= vs. 5-3=… 7+2=
- Memory updating e.g., running memory task: F…J…H…S…Y…
- Inhibition of prepotent responses e.g., Stroop task: BLUE vs. RED
- there is a correlation between all of these between .4 and .6
- these are central aspects of WM
Executive processes
- eg: attempting to retrieve elements into the direct access region from activated memory
- Executive processes serve executive functions, Not a single “CE(O)”, More of an “executive committee”
Describe the relationship between WM and executive functions
Three executive functions
* moderately correlated with each other (r’s > 0)
* but clearly separable (r’s < 1)
* differentially related to higher-level cognitive tasks
* Shifting à Wisconsin Card Sorting Task
* Updating à Random number generation
* Inhibition à Tower of Hanoi
Explain what is meant by “unity and diversity of executive functions” (Miyake
these demonstrate that working memory and executive functioning are closely related
- Sometimes EF’s are defined as central aspects of WM (e.g., attentional control)
- Sometimes WM is defined as an EF
Wisconsin Card Sorting Test (WSCT) test for shifting abilities
- cards differ in terms of colour, shape, & number
- participant required to sort cards according to “rule” that is only known by test administrator
- rule changes periodically
- response perseveration = no. of cards before participant changes their sorting strategy when rule changes
Tower of Hanoi test for inhibition
- 3 discs on a peg with 3 pegs,
- Move tower from one side to the other
- Move only one disc at a time -
- Larger disk must never go on top of smaller disk
- “Illegal” moves must be inhibited
Random number generation task tests for updating
ADHD
- impaired inhibition à hyperactivity, distractibility & impulsivity *
Schizophrenia
- impaired shifting and updating
Frontal lobe dementia (Morbus Pick)
- executive functions are “frontal lobe functions” * etc. use Wisconsin card sorting test to diagnose
Describe the relation between WM and other cognitive processes, in particular higher-level cognition (e.g., language comprehension, intelligence)
WM is the engine of cognition
WM capacity predicts:
- Attentional control (Kane et al., 2001)
- Reading performance (Daneman & Carpenter, 1980)
- Math skills (Hitch, Towse, & Hutton, 2001) * Reasoning (Kyllonen & Christal, 1990)
- Skill acquisition (Woltz, 1988)
- Intelligence (Oberauer et al., 2005)
- WM the “engine of cognition” (Jonides, 1995)
WM and intelligence
- Working memory but not STM predicts fluid intelligence
Understand the difference between a simple span task and a complex span task
Complex span task performance predicts higher cognitive abilities
- Complex span task performance (WM capacity) is an extremely good predictor of higher-level cognitive abilities
- Better predictor than simple span tasks (STM capacity)
- it measures processing abilities as well as retrieval (WM)
Simple span tasks only measure
- storage
- only measures retrieval from STM
