title: The conscious perception of the sensation of fatigue.
abstract: 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.
authors.affiliation: Human Motor Control Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA. agibson@sprots.uct.ac.za
authors.forename: Alan
authors.initials: A
authors.lastname: St Clair Gibson
authors.forename: Denise A
authors.initials: DA
authors.lastname: Baden
authors.forename: Mike I
authors.initials: MI
authors.lastname: Lambert
authors.forename: E Vicki
authors.initials: EV
authors.lastname: Lambert
authors.forename: Yolande X R
authors.initials: YX
authors.lastname: Harley
authors.forename: Dave
authors.initials: D
authors.lastname: Hampson
authors.forename: Vivienne A
authors.initials: VA
authors.lastname: Russell
authors.forename: Tim D
authors.initials: TD
authors.lastname: Noakes
mesh_terms: D001364:Awareness; D001921:Brain / Q000503:physiopathology; D004644:Emotions / Q000502:physiology; D005221:Fatigue / Q000473:pathology / Q000503:physiopathology / Q000523:psychology*; D006801:Humans; D008962:Models, Theoretical; D009043:Motor Activity / Q000502:physiology; D010465:Perception / Q000502:physiology