Ergonomics (human factors) is the scientific discipline concerned with understanding interactions among humans and other elements of a system, applying theory, principles, data, and methods to design systems that optimize human well-being and overall system performance. Cognitive ergonomics specifically addresses mental processes — perception, memory, reasoning, and motor response — as they affect interactions between humans and systems.
Key Structures
- Prefrontal cortex (task management) — The anterior portion of the frontal lobe, critical for executive functions including planning, decision-making, working memory, and cognitive control.
- Motor cortex (physical performance) — The precentral cortical region that plans, initiates, and executes voluntary movements through corticospinal projections, particularly in relation to physical performance.
- Somatosensory cortex (proprioception)
- Anterior cingulate cortex (effort monitoring) — A medial frontal region involved in conflict monitoring, error detection, and the allocation of cognitive control, particularly in relation to effort monitoring.
- Cognitive Load Theory — An instructional design framework holding that learning is optimized when teaching methods align with the limited capacity of working memory and the unlimited capacity of long-term memory.
- Signal Detection Theory — A mathematical framework for analyzing perceptual and cognitive decisions under uncertainty, separating an observer's sensitivity from their response bias.
- Vigilance — The ability to sustain attention and detect rare, unpredictable signals over prolonged periods of time — a capacity that typically declines within 15-30 minutes of continuous monitoring.
Key Functions
Applies knowledge of human cognitive and physical capabilities to design workplaces, tools, and tasks that optimize performance, safety, and well-being while minimizing error and fatigue.
Cognitive Ergonomics
Cognitive ergonomics applies cognitive psychology to system design. Display design draws on perception research (contrast, color coding, Gestalt grouping) to ensure critical information is salient and interpretable. Control design applies stimulus-response compatibility research to ensure controls map intuitively to their effects. Alarm design addresses the signal detection theory trade-off between sensitivity and false alarm rate — too many false alarms lead to "alarm fatigue" where operators ignore genuine warnings. Workload assessment uses cognitive load theory to ensure operators are neither overloaded (risking errors) nor underloaded (risking vigilance decrements).
James Reason's model of human error distinguishes between slips (correct intention, wrong action), lapses (correct intention, omitted action), mistakes (wrong intention due to faulty reasoning), and violations (deliberate deviations from rules). The Swiss cheese model shows how system accidents result from the alignment of holes in multiple defensive layers. These models have been influential in healthcare (medication errors, surgical safety checklists), nuclear power, and transportation.
Applications
Ergonomics is applied in workplace design (computer workstations, operating rooms), transportation (vehicle controls, traffic systems), consumer products (appliance interfaces, medication packaging), and military systems (command-and-control interfaces). The field increasingly addresses the cognitive challenges of working with AI systems, including appropriate trust calibration and effective human-AI collaboration.
Disorders
- Repetitive strain injury — Injury to muscles, tendons, or nerves caused by repetitive movements, sustained postures, or forceful exertions.
- Occupational burnout — A syndrome of emotional exhaustion, cynicism, and reduced professional efficacy resulting from chronic workplace stress.
- Work-related musculoskeletal disorders
- Chronic fatigue — Persistent, debilitating fatigue not explained by medical conditions, associated with cognitive dysfunction and altered neural processing.