Working memory model Flashcards
What are the components of the WMM?
- Central executive (The Boss)
from left to right:
- Phonological loop (phonological store & articulatory control system)
- Episodic buffer
- Visuo-spatial sketchpad (visual cache & inner scribe)
Who came up with it?
Explain the concept of working memory?
- Baddeley & Hitch (1974)
- Working Memory was developed as new approach to understand STM
- WMM tries to overcome weaknesses of MSM
- WMM: STM is a ‘workspace’ where it carries out various tasks using old & new memories
- System links to LTM through episodic buffer
Explain the central executive?
Encoding?
Capacity?
Research?
- WMM ‘boss’
- All information passes to Central Executive (CE), then decides which component should process it
- Components can only communicate with each other via the CE
- Decides what WM
- Encoding: modality free: it can process information from any of 5 senses (auditory, visual etc.)
- Capacity: Limited
- Bunge (2000): Same brain areas active in single/dual task conditions
- Used FMRI scans to see parts of brain active when Pt’s doing 2 tasks
- Research shows more activation shown in dual task area: increased attentional demands placed on CE
Strength & weakness of CE?
- Strength: Versatile & important of WMM supported by evidence Bunge (2000)
- Weakness: CE is vague in explanation & process
- Suggests CE is singular which is unlikely
Explain the phonological loop?
Encoding?
Capacity?
Research?
- Phonological loop (PL) holds information in form of speech/sound
- 2 parts to PL:
- Phonological store (inner ear) deals with speech perception
- Articulatory control system (inner voice) rehearses info from PL (repeating info on a lop maintains info in the store)
- Encoding: Auditory info
- Capacity: Limited (2 seconds)
- Baddeley & Hitch: participants asked to perform two tasks at the same time (dual task)
- Digit span task required them to repeat a list of numbers & verbal reasoning task which required them to answer true/false to various questions (e.g., B is followed by A?)
- When number of digits increased (digit span tasks) participants took longer to answer reasoning questions (only fractions of a second longer)
- Pt’s didn’t make any more errors in the verbal reasoning tasks as number of digits increased
- Research showed verbal reasoning task made use of CE & digit span task made use of PL
Explain the episodic buffer?
Encoding?
Capacity?
Research?
- Episodic buffer integrates information from several sources to create unified memories
- System works between the PL & VSS
- EB recalls info from LTM to be used in STM when required
- Encoding: Informational
- Capacity: Limited (4 chunks of info)
- Alkhakifa (2009)
- Patient with impaired LTM showed STM capacity up to 25 items
- This exceeds the capacity of both PL & VSSP
- Research shows existence of episodic buffer seems to hold items in WM until recalled
Strength & weakness of episodic buffer?
- Strength: Scientific research from brain scans
- EB seems to be in both hemispheres (mainly in hippocampus - memory part)
- Weakness: EB is not understood fully as it was added to WMM later
- Research on EB is still in infancy
- Lack of research impacts credibility of the slave system
Explain the visuo-spatial sketchpad?
Encoding?
Capacity?
Research?
- Inner-scribe for spatial relations
- Visual-cache: holds visual & spatial info e.g. what things look like
- Sketchpad helps us navigate where we are in regards to objects
- Also uses visual & spatial info from LTM e.g. memory of house layout
- Encoding: Visual
- Capacity: Limited (3-4 objects)
- Brookes (1968): Pt’s 1/3 conditions (tapping response, pointing to yes/no, saying aloud yes/no)
- In response to a mentally visualised letter (e.g. K)
- Asked to response to questions about letter by 1/3 methods
- Pt’s faster & accurate when responding verbally/tapping
Research shows: Using ltd capacity component for same task, they interfere with each other i.e. shows VSS is limited processor & separate
Strength & weakness of VSS?
- Strength: Plays important role in keeping track of where we are in relation to other objects as we move through our environment
- Weakness: Model implies all info starts visual then turns spatial, unlikely to be true all the time
- Lieberman (1980) argues blind people have good spatial awareness with no visual info
- Lieberman suggests VSS should be categorised into visual & spatial compartments
AO3 WMM
Case study support?
KF case study
P - Naturalistic research support from KF
E - KF suffered brain damage from motorcycle accident damaging STM
- KF’s injury mainly for verbal info
- Memory for visual info largely unaffected
E - Shows there are separate STM components for VSS & phonological loop
L - Shows further support for components of WMM
AO3 WMM
Research support?
Alkhakifa (2009)
P - Supporting research from Alkhakifa (2009)
E - Showed that a patient with impaired LTM showed STM capacity of up to 25 items
E - This exceeds capacity of phonological loop & VSS
L - Suggests existence of episodic buffer that seems to hold items in working memory until they are needed & works between both the loop & VSS to do this
AO3 WMM
Artificial lab experiments?
P - Much research evidence comes from artificial lab experiments into memory
E - Because study is artificial, lacks ecological validity & could give rise to demand characteristics
E - So Pt’s in STM studies for the WMM could purposefully alter the results to suit per say Baddeley & Hitch’s 1976 study
L - Implies research evidence lacks credibility
AO3 WMM
Practical applications?
Park (1999)
P - Concept of WMM had useful practical applications
E - Park (1999) concluded patients with schiz have problems with working memory that can be identified in dual tasks as seen in WMM
E - So schiz can be diagnosed on basis of testing an individuals working memory
L - Implies WMM has useful applications to society
