Measures of Workload, Stress and Secondary Tasks

  • Christopher D. Wickens
Part of the NATO Conference Series book series (NATOCS, volume 8)


In the context of my approach, the concept of operator workload is defined in terms of the human’s limited processing resources. Operator workload scales monotonically with the extent to which the tasks performed by the operator utilize these limited resources. Since workload is defined in terms of the hypothetical construct of “processing resources”, some operational definition must be provided of the latter term. This definition is provided in terms of secondary task performance.


Primary Task Secondary Task Tracking Task Processing Resource Concurrent Task 
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Copyright information

© Springer Science+Business Media New York 1979

Authors and Affiliations

  • Christopher D. Wickens
    • 1
  1. 1.Department of PsychologyUniversity of IllinoisChampaign-UrbanaUSA

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