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Le bâillement : de l'éthologie à la médecine clinique
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 Le bâillement : un comportement universel
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Le bâillement foetal
Le bâillement, du réflexe à la pathologie
Le bâillement : de l'éthologie à la médecine clinique
Le bâillement : phylogenèse, éthologie, nosogénie
 Le bâillement : un comportement universel
La parakinésie brachiale oscitante
Yawning: its cycle, its role
Warum gähnen wir ?
Fetal yawning assessed by 3D and 4D sonography
Le bâillement foetal

mise à jour du
11 novembre 2013
Med Hypotheses
2013; 81(6): 1034-5
Frequent yawning as an initial signal of fever relief
Gallup AC, Gallup JA.
Psychology Department, SUNY College at Oneonta, NY, United States


Andrew C. Gallup. Yawning and the thermoregulatory hypothesis
Research suggests that yawning provides a brain cooling function in homeotherms, and that excessive yawning may be a useful diagnostic indicator of abnormal thermoregulation in humans. Accordingly, the frequency of yawning should increase during instances of hyperthermia, but not fever (i.e., pyrexia), since this represents an elevation in the homeostatic set point rather than thermoregulatory failure. To our knowledge, no research has investigated the association between yawning frequency and fever in humans. Here we present the hypothesis that frequent yawning could be used as an initial signal for fever relief, either through the effectiveness of antipyretics or the natural break of a fever. Applications of this research include the improved behavioral monitoring of patients.
Thermoregulation in homeotherms requires preserving a relatively constant temperature, and deviations in this optimal range trigger a combination of autonomic and behavioral mechanisms controlled by the central nervous system [1]. Recently it has been proposed that yawning serves a thermoregulatory function, acting to counteract intermittent rises in brain temperature [2&endash;4]. Mechanisms by which yawning could promote brain cooling in humans include increased cerebral blood flow, countercurrent heat exchange, and evaporation of sinus mucosa within the paranasal sinuses [5].
Numerous reports have confirmed and replicated the specific predictions derived from this hypothesis, now referred to as the thermoregulatory theory (for a recent review and evaluation, see [6]). For instance, neurophysiologic research on rats shows that yawns are triggered during rapid increases in brain temperature ( 0.11 C), and following the completion of this motor pattern the previously rising temperatures quickly begin decreasing back to baseline levels [7]. Additional comparative research shows that the onset of yawning following physical stressors is positively correlated with elevated core temperatures in birds [8]. Furthermore, in a case report of a patient suffering from debilitating bouts of excessive yawning, mild hyperthermia (37.5 C) was documented immediately preceding the onset of yawning, and at the conclusion of these episodes an appreciable and consistent cooling effect was observed within the skull (oral temperature: 0.4 C) [9]
Alongside research depicting consistent fluctuations in brain and/or body temperature surrounding yawning events, a growing collection of behavioral studies has also demonstrated a clear association between yawning and ambient temperature manipulation/ variation in birds and mammals [10&endash;12]. Consistent with models of thermoregulatory physiology [13], yawning increases in frequency during initial rises in ambient temperature, but as temperatures continue to increase yawning rates begin to diminish since the ambient air provides the cooling utility through countercurrent heat exchange [10,14]. Instead, more effective evaporative cooling mechanisms are triggered as ambient temperatures approach or exceed internal temperature [10].
A similar, perhaps counterintuitive, prediction of the thermoregulatory theory states that yawning should not increase during fever (i.e., pyrexia) [3]. Fever represents a regulated elevation in body temperature when concentrations of prostaglandin E2 increase in the brain after a rise in the hypothalamic set point [15], and it is well-established that fever is an adaptive and essential defensive response to infection by pathogens [16]. Therefore, unlike thermoregulatory failure (i.e., hyperthermia), typical cooling responses, such as yawning, are not triggered to counteract heightened temperatures produced by fever. However, an increase or decrease in core temperature from the revised set point of the fever will stimulate normal thermoregulatory mechanisms [17], and thus a normal frequency of yawning could still be observed after the fever is determined, though this has not been empirically demonstrated.
Antipyretic medications such as acetaminophen, aspirin and other nonsteroidal anti-inflammatory drugs are commonly used to treat fever by reducing the hypothalamic set point. Most of these drugs work by inhibiting the enzyme cyclooxygenase and reducing levels of prostaglandin E2 within the hypothalamus, though other mechanisms of action have also been suggested [18]. Immediately following the use of antipyretics, however, the deviation from actual temperature and the new set point should also activate thermoregulatory mechanisms to contribute in cooling core temperatures back to baseline. Therefore, it is hypothesized that frequent yawning, as well as other less overt cooling responses, could signal the initial effectiveness of these medications. In addition, similar to sweating, recurrent yawns may also signal the break of a fever in the absence of treatment. It has already been suggested that excessive or repetitive yawning could be useful for identifying abnormal thermoregulation associated with certain anti-depressant medications [19,20] or underlying thermal dysfunction [10,21]. If this hypothesis is correct, observational monitoring could also be applied when treating patients with fever where frequent yawning could be easily recognized and recorded.
[1] Bicego KC, Barros RCH, Branco LGS. Physiology of temperature regulation: comparativeaspects. Comp Biochem Physiol A Mol Integr Physiol 2007;147:616&endash;39.
[2] Gallup AC, Gallup Jr GG. Yawning as a brain cooling mechanism: nasal breathing and forehead cooling diminish the incidence of contagious yawning. Evol Psychol 2007;5:92&endash;101.
[3] Gallup AC, Gallup Jr GG. Yawning and thermoregulation. Physiol Behav 2008;95:10&endash;6.
[4] Gallup AC. A thermoregulatory behavior. In: Walusinski O, editor. The mystery of yawning in physiology and disease, frontiers of neurology and neuroscience. Basel, Switzerland: Karger AG &endash; Medical and Scientific Publishers; 2010. p. 84&endash;9.
[5] Gallup AC, Hack GD. Paranasal sinuses and selective brain cooling in humans: a ventilation system activated by yawning? Med Hypotheses 2011;77:970&endash;3.
[6] Gallup AC, Eldakar OT. The thermoregulatory theory of yawning: what we know from 5 years of research. Front Neurosci 2013;6:1&endash;13.
[7] Shoup-Knox ML, Gallup AC, Gallup Jr GG, McNay EC. Yawning and stretching predict brain temperature changes in rats: support for the thermoregulatory hypothesis. Front Evol Neurosci 2010;2:1&endash;5.
[8] Miller ML, Gallup AC, Vogel AR, Clark AB. Handling-stress initially inhibits, but then potentiates yawning in budgerigars (Melopsittacus undulatus). Anim Behav 2010;80:615&endash;9.
[9] Gallup Jr GG, Gallup AC. Yawning and thermoregulation: two case histories of chronic, debilitating yawning. Sleep Breath 2010;14:157&endash;9.
[10] Gallup AC, Miller ML, Clark AB. Yawning and thermoregulation in budgerigars (Melopsittacus undulatus). Anim Behav 2009;77:109&endash;13.
[11] Gallup AC, Miller ML, Clark AB. The direction and range of ambient temperature influences yawning in budgerigars (Melopsittacus undulatus). J Comp Psychol 2010;124:133&endash;8.
[12] Gallup AC, Miller RR, Clark AB. Changes in ambient temperature trigger yawning but not stretching in rats. Ethology 2011;117:145&endash;53.
[13] Scholander PF, Hock R, Walters V, Johnson F, Irving L. Heat regulation in some Arctic and tropical mammals and birds. Biol Bull 1950;99:237&endash;58.
[14] Gallup AC, Eldakar OT. Contagious yawning and seasonal climate variation. Front Evol Neurosci 2011;3:1&endash;4.
[15] Saper CB, Breder CD. The neurologic basis of fever. N Eng J Med 1994;330:1880&endash;6.
[16] Kluger MJ, Kozak W, Conn CA, Leon LR, Soszynski D. The adaptive value of fever. Infect Dis Clin North Am 1996;10:1&endash;20.
[17] Cooper KE. Fever and antipyresis: the role of the nervous system. Cambridge: Cambridge University Press; 1995.
[18] Aronoff DM, Neilson EG. Antipyretics: mechanisms of action and clinical use in fever suppression. Am J Med 2001;111:304&endash;15.
[19] Gallup AC, Gallup Jr GG. Venlafaxine-induced excessive yawning: a thermoregulatory connection. Prog Neuropsychopharmacol Biol Psychiatry 2009;33:747.
[20] Gallup AC, Gallup Jr GG. Medical implications of excessive yawning in relation to thermoregulatory dysfunction. Eur J Neurol 2009;16:e120.
[21] Gallup AC, Gallup Jr GG, Feo C. Yawning, sleep, and symptom relief in patients with multiple sclerosis. Sleep Med 2010;11:329&endash;30.