1. Comp 15 - Usability and Human Factors
Unit 3a - Cognition and Human Performance
This material was developed by Columbia University, funded by the Department of Health and Human Services, Office of the National Coordinator for Health Information Technology under Award Number 1U24OC

2. Health IT Workforce Curriculum Version 2.0/Spring 2011
Overview
Cognition and Human Computer Interaction in a cognitive engineering approach
A model of human information processing including perception, attention, memory and cognition
Mental models and interactive behavior
Distributed cognition
Cognition and Human Computer Interaction in a cognitive engineering approach
A model of human information processing including perception, attention, memory and cognition
Mental models and interactive behavior
Distributed cognition
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

3. Cognition and Human Computer Interaction (HCI)
HCI is intersection between psychology/ social sciences and computer sciences/ technology
HCI seeks to understand and support human beings interacting with technology
Drawing on basic science research
Applied cognitive HCI work
Study of cognition and information processing is increasingly viewed as central to advances in HCI
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

4. HCI: Cognitive Engineering Approach
Principles, methods and tools to assess and guide design of computerized systems to support human performance
Focus on attention, perception, memory, comprehension, problem solving, and decision making
Analysis of cognitive tasks and processing constraints imposed by the human information processing system
Principles, methods and tools to assess and guide design of computerized systems to support human performance
Focus on attention, perception, memory, comprehension, problem solving, and decision making
Analysis of cognitive tasks and processing constraints imposed by the human information processing system
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

5. Cognitive Theory and HCI
Informative
Useful research findings
Predictive
Providing tools to model user behavior
Prescriptive
Providing advice for design or evaluation
Explanatory
Accounting for user behavior
Generative
Provide design dimensions and constructs to inform design and selection of external representations
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

6. Driving with a Computer Keyboard
“Imagine trying to drive a car using a computer keyboard. The four arrow keys are used for steering, the space bar for braking and the return key for accelerating. To indicate left you need to press the F1 key and to indicate right, the F2 key. To sound your horn you need to press the F3 key. To switch the headlights on you need to use the F4 key and the F5 key for the windshield wipers. Now imagine as you were driving along a road a ball is suddenly kicked in front of you. What would you do? Bash the arrow keys and the space bar madly while pressing the F3 key?”
Image of computer keyboard on top of a car steering wheel:
Preece, J. Rogers, Y. & Sharp, H. (2007) Interaction Design: Beyond Human-Computer Interaction. 2nd Edition. New York, NY: John Wiley & Sons. P. 92
Preece, J. Rogers, Y. & Sharp, H. (2007) Interaction Design: Beyond Human-Computer Interaction. 2nd Edition. New York, NY: John Wiley & Sons. P. 92
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

7. Human Information Processing
Human information processing theory deals with how people receive, store, integrate, retrieve, and use information.
A basic HIP model recognizes 3 subsystems:
Perceptual system processing sensory information
Motor system controls action
Cognitive system provides the processing that connects the two systems
HIP model provides a basis from which to make predictions about human performance
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

8. A Model of Human Information Processing
Perception
Working Memory
Long -
Term Memory
Sensory
Register
Hearing
Vision
Olfaction
Haptic
Response
Selection
Execution
Feedback
Attention
Resources
Perceptual Encoding
Central Processing
Responding
Thought
Decision Making
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

9. Perception Complex dynamic process
Perception: Attach meaning to sensory inputs
Maps incoming sensory information into a mental representation stored in long term memory
Mapping proceeds by processes that often occur concurrently:
Bottom-up feature analysis
Top-down processing
Ability to respond consistently to certain combination of features because of learned associations
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

10. Gestalt Organization Principles
Perceptual organizing principle:
How we perceive structure in our environment
Proximity
Containment
Similarity
Closure
Continuation
Basic principles with clear implications for web design
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

11. Health IT Workforce Curriculum Version 2.0/Spring 2011
No Clear Grouping
Image of 16 red boxes forming a 4 x 4 square.
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

12. Health IT Workforce Curriculum Version 2.0/Spring 2011
Proximity
Image of 16 red boxes also 4 x 4, but more spread out.
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

13. Health IT Workforce Curriculum Version 2.0/Spring 2011
Containment
Image of 16 red boxes, 4 x 4, but split into 2 groups of 8.
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

14. Health IT Workforce Curriculum Version 2.0/Spring 2011
Similarity
Image of 16 boxes, arranged 4 x 4, alternating rows of color (red, blue, red, blue).
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

15. Health IT Workforce Curriculum Version 2.0/Spring 2011
Closure
Image of 14 red boxes arranged into large square with some spaces.
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

16. Health IT Workforce Curriculum Version 2.0/Spring 2011
Anyone’s Guess
Image of 16 shapes, various colors (red and blue), various types of shapes (squares and circles).
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

17. Airport Status Example
Was the delay Boston or Westchester?
Was the delay Boston
or Westchester?
Newark
On time
JFK
La Guardia
Newberg
Philadelphia
Boston
Delay
Westchester
Long Island
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

18. Health IT Workforce Curriculum Version 2.0/Spring 2011
Schedule 1
Newark
Philadelphia
On time
On time
JFK
Boston
On time
Delay
La Guardia
Westchester
On time
On time
Newberg
Long Island
On time
On time
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

19. Health IT Workforce Curriculum Version 2.0/Spring 2011
Simple Improvement 1
Newark
Philadelphia
On time
On time
JFK
Boston
On time
Delay
La Guardia
Westchester
On time
On time
Newberg
Long Island
On time
On time
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

20. Health IT Workforce Curriculum Version 2.0/Spring 2011
Simple Improvement 2
Newark On Time
Philadelphia - On Time
JFK On Time
Boston Delay
La Guardia - On Time
Westchester - On Time
Newberg On Time
Long Island - On Time
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

21. Health IT Workforce Curriculum Version 2.0/Spring 2011
Human Attention
Selective Mechanism
Resource needed for information processing
Limited
Sharable
Flexible
Selective Mechanism
Resource needed for information processing
Limited
Sharable
Flexible
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

22. Selective Attention
Ability to ignore extraneous information and focus on relevant inputs
Performance typically declines as the number of sources of information increases
Humans can only process information at a finite rate
Information overload results in errors
Ability to ignore extraneous information and focus on relevant inputs
Performance typically declines as the number of sources of information increases
Humans can only process information at a finite rate
Information overload results in errors
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

23. The Case of Bird Watching
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

24. Computer Provider Order Entry Systems
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Health IT Workforce Curriculum Version 2.0/Spring 2011 24

25. Representational Effect
External representations such as images, graphs, tables, icons, audible sounds, written symbols are instruments of thinking
Representational Effects: Different representations of a common abstract structure (same meaning) can significantly affect performance
Compare 37 x 93 and XXXVII x XCIII
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

26. Health IT Workforce Curriculum Version 2.0/Spring 2011
Digital vs. Analog
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

27. Glucose and BP Representations
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011

28. Risk Representations (Ancker, 2007)
Component 15/Unit 3a
Health IT Workforce Curriculum Version 2.0/Spring 2011