Some Remarks on Mental Load

  • A. F. Sanders
Part of the NATO Conference Series book series (NATOCS, volume 8)


This paper aims to present an analysis of the concept of mental load from the point of view of human performance theory. In the first section the theoretical status of the concept of mental load is considered. It is concluded that it is based upon common sense, which cannot be supposed to be empirically founded in a simple way. Then an outline is given of the main procedures of measurement. The next section describes a number of theoretical bases which are all related to some kind of limited capacity notion. It is concluded that the original idea of channel capacity in terms of information theory fails to provide a sound theoretical framework. Other capacity concepts in terms of limited capacity processors and in terms of effort are described. Three types of processors are distinguished, which have different consequences for the measurement of mental load.

The fourth section describes some experimental trends. It is concluded that a multichannel type of processor, composed of a network of internal mechanisms is most favoured by the data. This has the consequence that mental load cannot be conceived of as a single dimension. The question is which mechanisms are involved in a task and to what extent. Performance failures occur if a single mechanism is overloaded, but that does not imply that other mechanisms are also overloaded. Ultimately a task may be described therefore in terms of a pattern of mental load. Some consequences for applied work are discussed.


Channel Capacity Dual Task Choice Reaction Time Task Variable Psychological Refractory Period 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media New York 1979

Authors and Affiliations

  • A. F. Sanders
    • 1
  1. 1.Institute for Perception TNOSoesterbergThe Netherlands

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