IE 311 Ergo 2 - 1 Introduction to Cognitive Ergonomics
Page 1: Introduction
Introduction to Cognitive Ergonomics
Compiled and Prepared by Hazel A. Caparas, MSIE, ASEAN Eng.
Page 2: Learning Objectives
Understand the definition, scope, and application of Cognitive Ergonomics.
Grasp the basic concepts of:
Human Information Processing Model
Signal Detection Theory
Absolute Judgment
Vigilance
Information Theory
Memory and Learning
Mental Workload
Visual Displays
Auditory Displays
Usability Theories
Usability Evaluation
Page 3: Understanding Ergonomics
Objective of Human Factors Engineering/Ergonomics:
Understand interactions between people and their environment.
Optimize human well-being and overall system performance.
Page 4: Dimensions of Ergonomics
Source: Handbook of Human Factors and Ergonomics, Fourth Edition, John Wiley & Sons, Inc. (2012)
General dimensions of ergonomics discipline discussed.
Page 5: Branches of Ergonomics
Physical Ergonomics
Cognitive Ergonomics
Organizational Ergonomics
Page 6: Emerging Areas in Ergonomics (1-7)
Methodology for work organization and design
Work-related musculoskeletal disorders
Usability testing for consumer electronics
Human-computer interface design (software)
Organizational design and psychosocial work organization
Ergonomic design of physical work environments
Control room design in nuclear power plants
Source: “A Guide to Human Factors and Ergonomics, 2nd Edition,” 2006
Page 7: Emerging Areas in Ergonomics (8-15)
Training for ergonomists
High technology interface design
Human reliability research
Measurement of mental workload
Workforce cost calculation
Product liability
Road safety and car design
Technology transfer to developing countries
Source: “A Guide to Human Factors and Ergonomics, 2nd Edition,” 2006
Page 8: Human Work Taxonomy
Tasks producing force
Tasks coordinating sensorimotor functions
Tasks converting information to motor actions
Tasks converting information into output
Tasks producing information
Sources: (Karwowski, 1992; Grandjean, 1986; Luczak et al., 1999)
Page 9: Focus of Cognitive Ergonomics
Focuses on mental processes:
Perception
Memory
Information processing
Reasoning
Motor responses
Affects interactions among humans and system elements (Vicente, 1999; Hollnagel, 2003; Diaper and Stanton, 2004).
Page 10: Cognitive Ergonomics Defined
Studies behavioral and cognitive aspects between individuals and their environment mediated by artefacts.
Key cognitive processes include:
Diagnosis
Decision making
Planning
Page 11: Purpose of Cognitive Ergonomics
Studies cognition in work settings to:
Optimize human well-being
Enhance system performance
Focuses on the fit between cognitive abilities and limitations with machines, tasks, and environments.
Page 12: Importance of Human Factors
Enhances efficiency and productivity
Ensures safety
Assures tasks align with human capability
Improves human performance
Gains market acceptance
Reduces costs (economic, legal, social)
Page 13: Goals of Cognitive Function
Attention
Memory
Executive Function
Page 14: Human Involvement in Technology
Different roles in technology include:
Designers
Users (operators)
Maintenance personnel
Technology failure issues include:
Machine failure
Human error
Interaction-related system errors
Page 15: Physical vs Cognitive Ergonomics
Physical Ergonomics: Adjusts to the body.
Cognitive Ergonomics: Concerns brain processes:
Perception of information
Understanding and interpretation
Decision-making processes
Page 16: Comfort in Cognitive Ergonomics
A comfortable mind leads to:
Fewer errors
Improved performance and productivity
Page 17: Cognitive Applications
Examples include:
Designing user-friendly software interfaces
Creating comprehensible signs
Designing systems (like cockpits) to prevent catastrophic errors
Page 18: Human Information Processing Model
Model consisting of:
Perception
Decision and response selection
Response execution
Memory
Attentional resources are distributed across stages (Wickens, Gordon, and Liu, 1997).
Page 19: Components of Human Information Processing Model
Attentional Resources
Memory Stages:
Short-term sensory store
Decision and response selection
Working memory
Long-term memory
Feedback sourced from Wickens (1984).
Page 20: Man-Machine System
Interaction between operator and machine through interpretation, display instruments, perception, and control instruments.
Page 21: Man-Machine System Model
Components:
Human Sensory Display
Cognitive Inverter Processor
Motor Control
Page 22: Signal Detection Theory (SDT)
SDT defines how we identify signals amidst noise.
Four outcomes:
Hit
Correct rejection
False alarm
Miss
Page 23: Absolute Judgment
Involves differentiation without direct comparison.
Requires working memory for comparisons.
Page 24: Vigilance Explained
Known as sustained attention, this refers to maintaining alertness over time.
Vigilance may decrease (Giambra and Quilter, 1987).
Page 25: Information Theory
Science that quantifies and understands information, measured in bits.
A bit represents the information needed to choose between two equally likely alternatives.
Page 26: Memory and Learning
Working Memory: Temporary storage for processing information (short-term memory).
Long-Term Memory: Permanent storage for future retrieval.
Page 27: Understanding Mental Workload
Mental workload equals the portion of mental capacity needed for a task.
Mental Reserves: Difference between required versus available capacity.
Increased mental workload can lead to performance failures.
Page 28: Mental Workload Definition
Refers to demands on the human information processor.
Page 29: Human Error
Defined as the failure to complete actions as intended (error of execution) or using wrong strategies for goals (error of planning).
Page 30: Human Reliability Analysis
Quantitative assessment of operator error probability and performance success, with a focus on understanding error causes.
Page 31: Visual Displays
Recommended conditions for visual display use include:
Long and complex messages
Spatial references
Information to be referred later
No immediate action needed
Difficult hearing or overburdened situations
Stationary operators
Source: Deatherage (1972)
Page 32: Auditory Displays
Best used when:
Messages are short and simple
Events in time need reporting
Immediate action is required
Vision is compromised
Operators are moving
Source: Deatherage (1972)
Page 33: Usability Theories
Usability describes a product's ease of use.
ISO 9142 Definition: Effectiveness, efficiency, and satisfaction in achieving specific goals in a given environment.
Page 34: Usability Defined
Effectiveness: Accuracy/completeness of goal achievement.
Efficiency: Resources used relative to success in achieving goals.
Satisfaction: Positive attitudes and freedom from discomfort.
Page 35: Usability Evaluation
Usability testing collects feedback from end-users to improve product design.
Page 36: Usability Testing Process
Involves users testing products to help developers enhance user-friendliness and meet needs.
Page 37: Ergonomics Checklists (Information & Control Tasks)
Factors in information presentation:
Appropriate display method selection
Simplicity in information presentation
Avoidance of character confusion
Correct character size selection
Page 38: Ergonomics Checklists (Continued)
Avoidance of all-uppercase texts
Use of familiar typefaces
Good text/background contrast
Clarity of diagrams
Proper use of pictograms
Sound signals for warnings only.
Page 39: Ergonomics Checklists (Control Tasks)
Feedback sense through touch
Distinguishable controls by touch
Consistency in control locations and spacing
Considerations for control-display compatibility.
Page 40: Ergonomics Checklists (Control Tasks Continued)
Cursor control suitability for tasks
Consistency of control movements with expectations
Clarity on control objectives based on position
Accessibility of controls for female workers.
Page 41: Ergonomics Checklists (Control Tasks Continued)
Proper labels/symbols for controls
Limited use of color in control design.
Page 42: Human-Computer Interaction Checklists
Suitability of the dialogue for the task
Self-descriptive and easily controlled dialogue
User expectation conformity
Error tolerance and user learning suitability.
Page 43: Human-Computer Interaction Checklists (Continued)
Command language restriction for experienced users
Use of detailed menus for inexperienced users
Help menu fitting users’ ability levels
Selection of QWERTY layout for keyboards.
Page 44: Methods in Cognitive Ergonomics
Behavioral and Cognitive Methods include:
Observation
Heuristics
Interviews for usability assessment
Verbal protocol analysis
Focus groups
Hierarchical task analysis (HTA)
Systematic human error reduction.
Page 45: Methods in Cognitive Ergonomics (Continued)
Further methods include:
Predictive human error analysis (PHEA)
Situation awareness measurement
Keystroke level model (KLM)
Global assessment techniques.
Page 46: Evaluation Checklists
Cognitive Work Evaluation Checklist
Graphical User Interface Features Checklist
Display Design Checklist
Page 47: Fitting the Task to Man
Page 48: Reference Texts
Salvendy, G. “Handbook of Human Factors and Ergonomics, 4th Edition,” John Wiley & Sons, Inc., 2012.
Kroemer, K et al. “Ergonomics, How to Design for Ease and Efficiency, 2nd Edition,” Pearson Education, 2001.
Freivalds A. et al., “Niebel’s Methods, Standards and Work Design, 13th Edition,” McGraw-Hill, 2014.
Page 49: Reference Texts (Continued)
Helander M., “A Guide to Human Factors and Ergonomics, 2nd Edition,” Taylor & Francis Group, 2006.