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Human Supervisory Control
Memory & Attention
A Model of Human
Information Processing
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Perception
Working
Memory
& Cognition
Response
selection
Response
execution
Sensory
Processing
(STSS)
Long-term
memory
System Environment
(Feedback)
Attention
Resources
Selection
Wickens & Hollands, 2000
? STSS = short term sensory storage
? Perception drives bottoms-up processing while long term memory drives top-down processing
Working Memory
? Also known as short term memory
? Three components
– Verbal (phonological store & articulatory loop)
– Visuospatial sketchpad
– Central executive
? Temporary buffer
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FAA Human Factors
http://www.hf.faa.gov/Webtraining/Cognition/Memory/memory1.htm
Working Memory Limitations
? Limited capacity
– Miller’s magic “7 +/- 2”
? Chunking & parsing
– Skill & expertise
? Information will decay unless maintained in
working memory through the articulatory loop
(rehearsal) or stored in long term memory.
– A fundamental component of learning
? Memory lost within 30 seconds unless
rehearsed.
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Long Term Memory
? Semantic network of knowledge
– Knowledge is procedural, declarative, and general
– Encoded in terms of meaning and events
? Not a random process
? A loosely structured “database”
? Unlimited capacity
? Development of mental models
– An abstract mental structure that allows understanding and
insight into an event, problem, etc.
? How knowledge was encoded influences recall
? Perception vs. Long Term Memory
– Recognition is much easier than recall
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? Declarative – knowledge of facts
? We can identify thousands of different colors but in general can only name ~ 17.
Problems with Memory
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?Unreliable
? Recognition vs. recall
? Do we forget or does information decay?
FAA Human Factors
http://www.hf.faa.gov/Webtraining/Cognition/Memory/memory1.htm
More Problems with Memory
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? Retrieval and Inference
– False memories
? Effect of Prior Knowledge
– Memory reconstruction often uses general knowledge and
expectations to fill in the gaps
? Memory can distort perception in systematic ways.
– Tendency to overestimate colors, slow speeds (but
underestimate high ones!), distances, etc.
? Eyewitness testimony
– Framing effect
– Subjects shown film of automobile accident. Subjects
asked: Did you see a broken headlight? or Did you see the
broken headlight? (There was actually none.)
? Results: Subjects more likely to respond yes to the broken
headlight.
Memory & Automated
System Design
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? Calculations, comparisons, and workspace navigation
tasks which require extensive use of working memory
increases the mental workload for that task.
– Also increases likelihood of error.
? Can increase working memory capacity by using two
senses instead of one
? Promote consistent mapping
– Negative transfer
? Mental model support
– Training strategies
? Part task
? When Two S Better than One, Tindall-Ford, S., Chandler, P. and Sweller, J., Journal of Experimental Psychology: Applied, 3(4), 257-287 (1997).ensory Modes are
A Model of Human
Information Processing
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Working
Memory
& Cognition
Sensory
Processing
(STSS)
Response
selection
Response
execution
Perception
Long-term
memory
System Environment
(Feedback)
Attention
Resources
Selection
Wickens & Hollands, 2000
? STSS = short term sensory storage
Attention
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? Three general categories
? Selective
? Cognitive tunneling
?Focused
? Environmental distractions
?Divided
? Time-sharing
? Attention is perceptually driven
? We tend to notice significant changes in light,
motion, temperature, sound, color, novelty, or
information complexity
? Cocktail Party Phenomenon
Attention & Visual Perception
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? Peripheral vision (rods)
– Helps to see movement, change
– Poor acuity and brightness
? Foveal vision
– Focused perception (cones)
– Helps to see details, color
– Pursuit & saccadic movements
? Saccades
– Eye “jumps” from one spot to next
– Dwell times
? Scanning versus target search
– Both occur in supervisory control
Vigilance & Attention
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? Vigilance – Monitoring for signal detection over
extended periods of time (e.g. radar watch, airport
security, etc.)
? People cannot maintain vigilance past 30 minutes in low
workload monitoring conditions .
High mental
workload is
problematic
Vigilance is
problematic
Better
Performance
Worse
Low High
Attentional demand
Designing to Direct Attention
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? Spatial Proximity
– Promotes divided attention
– Heads-up display
– Conformal symbology
? Salience of visual cues
– Intelligent cueing
? Proximity Compatibility Principle
– Display v. processing proximity
– Configural displays
? Emergent features & pattern recognition
? What about auditory attention?