The Conscious Perception of the Sensation of Fatigue


In this review, fatigue is described as a conscious sensation rather than a physiological occurrence. We suggest that the sensation of fatigue is the conscious awareness of changes in subconscious homeostatic control systems, and is derived from a temporal difference between subconscious representations of these homeostatic control systems in neural networks that are induced by changes in the level of activity. These mismatches are perceived by consciousness-producing structures in the brain as the sensation of fatigue. In this model, fatigue is a complex emotion affected by factors such as motivation and drive, other emotions such as anger and fear, and memory of prior activity. It is not clear whether the origin of the conscious sensation of fatigue is associated with particular localised brain structures, or is the result of electrophysiological synchronisation of entire brain activity.

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The Medical Research Council of South Africa, National Research Foundation of South Africa, Technology and Human Resources for Industry Programme of South Africa and the Harry Crossley Research Funds of the University of Cape Town provided financial assistance for studies described in this review. The authors have no conflicts of interest that are directly relevant to the content of this manuscript.

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Correspondence to Alan St Clair Gibson.

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Gibson, A.S., Baden, D.A., Lambert, M.I. et al. The Conscious Perception of the Sensation of Fatigue. Sports Med 33, 167–176 (2003).

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  • Chronic Fatigue Syndrome
  • Conscious Perception
  • Conscious Knowledge
  • Neural Network Activity
  • Subconscious Level