Working memory - 2 Flashcards
What is purpose of VSSP?
- Maintaining and manipulating visa-spatial information
- spatial orientation
- solution of visuo-spatial problems
- Interface between visual and spatial information
- bind visual information with motor/haptic/tactile information
Evidence for VSSP
- sketchpad disrupted by requiring participants to tap repeatedly a specified pattern of keys or locations, a procedure that impairs the use of visuospatial imagery
- unattended patterns or visual noise may disrupt the visual component of the system
- Corsi span (test in which task is to reproduce visuo-spatial sequences using set of 9 identical cubes mounted at locations on board) and auditory digit span impaired independently in patients with different lesions
How was it proposed that VSSP can be divided?
- visual cache: stores info about visual form and colour
- inner scribe: deals with spatial and movement information (and basic mechanism for rehearsal)
How does the stroke victim LH perform?
- performed much better on memory tasks involving spatial processing than on tasks involving the visual aspects of imagery (eg, judging animal sizes)
- occipital lobe impaired
What is the central executive?
- the ‘black box’
- drives the system; allocates the resources
- has no storage capacity
- limited capacity so cannot attend to many things at once
- temporary activation of long-term memory
What were the 4 assumed functions of the central executive?
- the coordination of simultaneous tasks and task switching
- the control of encoding and retrieval strategies of temporarily stored information (also when retrieved from the long-term store)
- the selection of attention and inhibitory processes
- the retrieval and manipulation of long-term stored information
What was the study investigating the Central Executive?
-asked participants to think of random digits that bore no connection to each other (by tapping in numbers on a keyboard) Either carried out on its own, or with one of the following tasks:
Reciting the alphabet
Counting from 1
Alternating between letters and numbers e.g. A1 b2 c3
What was the finding of the central executive study?
-generated number stream was much less random in condition 3 – Baddeley said they were competing for the same central executive resources
What was the binding problem?
- how into from two subsidiary systems could be bound together
- because in real world we recall things in multi modal format
What theory was proposed to solve binding problem?
-Episodic buffer
Purpose of episodic buffer
- integrates info across modalities and from different sources
- limited storage capacity
- buffer retrieval through conscious awareness
- originally thought to be capable of manipulating information; but now thought to be a passive structure on which bindings achieved elsewhere can be displayed
What does episodic buffer account for?
- finding that amnesic patients can retain relatively large amounts of complex information briefly (e.g., sentence span)
- findings that articulatory suppression does not have devastating effect on recall of visually presented numbers (drops from 7 to 5 digits)
What is binding process unaffected by?
-attentional load
What is attention useful for?
- Visual bindings (objects colour, shape)
- Verbal bindings (words into chunks)
What inför feeds into VSSP?
- Visual
- Spatial
- Haptic
