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.
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.