What is task switching?
Participants incur a time cost when they switch from one simple task to another
Can adequate preparation remove the switch cost?
- No there is always a residual cost
- Task preparation is not the whole story
- Deciding on the response for the current stimulus may be affected by the response associated with the stimulus for the alternative task
Why is disengaging an important factor in task switching?
- To change tasks someone needs to disengage from the inappropriate task
- Disengaging is a major factor when going from an easier task to a harder task (it is easier to do than to go from a hard task to an easy task)
What are the effects of practice (automaticity)?
Kahneman’s capacity theory:
- Over-learned tasks become automatic and consume fewer resources
Effects:
- Improves performance
- Reduces task effort
- Facilitates re-structuring and co-ordination of concurrent tasks
What are the characteristics of automatic processes
- Without awareness
- Without conscious deliberation / obligatory
- Without expenditure of resources
- Fast
- Rigid/habitual
When can automaticity become a controlled process?
- When there is a higher task load and when there is interference in a task
- Automatic performance can be reduced with additional demands
What is working memory?
- Working memory is the domain of conscious thought
Working memory involved in making decisions and initiating actions based on plans and in response to environmental input
Working memory involved in directing attention
What is the capacity of working memory?
Around 7 items
What is in Baddeley’s working memory model?
Central executive:
- Phonological loop
- Viso-spatial sketchpad
Episodic buffer
What is the central executive?
- An attention controller that is an interface between working memory systems and long-term memory
- Does not have its own storage capacity
What are some functions of the central executive?
- Co-ordination of the subsidiary WM systems
- Control of encoding and retrieval strategies
- Switching of attention
- Mental manipulation of material held in the slave systems
What is the phonological loop?
- Maintains verbal, sequential information in a phonological (sound-based) code
2 components:
Verbal store (inner ear)
The subvocal articulatory rehearsal process (inner voice)
What happens in the phonological loop when information is rehersed?
- Information decays after 2 secs, unless maintained by rehearsal
- Articulatory rehearsal also may be used to enter information into the store
E.g. Remember a password or phone number in the short-term
What is the visuo-spatial sketchpad?
- Visuospatial rather than verbal encoding material
(looking at images and not describing it by words)
What are the functions of visuo-spatial sketchpad?
- Planning and execution of spatial tasks (e.g. in sport, driving ect)
- Manipulating visual images
- Keeping track of changes in the visual perceptual world
Maintaining orientations in space and directing movement - Comprehending certain verbal information
What is visual / short-term memory? (VSTM)
- Memory buffer that allows the retention of visual information, for a short time period, when it is out of view
- Holds 3-4 items
- Gives rise to a coherent and continuous representation of the visual world, that would otherwise be disrupted by objects being occluded or saccadic eye movements
- Allows relevant visual information to be used when undertaking goal-directed behavior and thoughts
What is the similarity effect?
(phonological loop)
- Similarity effect
More confusion in immediate serial recall for letters with similar-sounding names - Recalling order information is the problem
(letters that sound similar are harder to remember than ones that sound different)
What evidence is there for the phonological loop?
- Similarity effect
- Irrelevant speech effect
- Word length effect
- Concurrent articulation
What is the irrelevant speech effect?
- Speech impairs serial verbal recall of visually presented material
Music interferes sometimes
What is the word length effect?
- Immediate memory span declines with the spoken duration of the list items
(people remember shorter words better than longer words)
How do we interpret the word length effect?
- It reflects the speed of subvocal rehearsal and hence the rate of refresh of the memory trace
(Less time to rehearse the word) - Rehearsal involves central programming of speech but no output
What is concurrent articulation?
-Words have similar-sounding syllabi so they are easier to remember
-This abolishes the similarity effect
What is the phonological loop for?
- Vocabulary learning- particularly for children, learning a new language
What is the nature of V-S sketchpad
It is divided into two main sections:
- Visual cache (stores visual patterns)
Inner-scribe (spatially based rehearsal)
Does not require visual input
