the yawning takes place in three phases, followed by a feeling of well-being and relaxation: a long inhalation, an acme, a rapid exhalation, sometimes accompanied by a stimulation from tear glands and whether or not associated with stretching. Its function is only incompletely elucidated.
Without improving cerebral oxygenation, as has been repeated for centuries, the yawning appears as a stimulation of our vigilance; it plays a role in non-verbal communication, especially in primates, in whom he is testosterone-dependent.
The process of yawning involves many neurotransmitters ; the dopamine plays a central role, by activating the production of oxytocin by the paraventricular nucleus of thehypothalamus.
Thanks to a 3D ultrasound to which we added a temporal dimension, scientists have distinguished yawns in fetuses. By determining the frequency based on age, they hope to detect developmental defects. © Courtesy of Wolfgang Moroder
Oxytocin activates the secretion cholinergic of the’seahorse and theacetylcholine triggers yawning by acting on muscarinic receptors in the muscles of the larynx, of the face and the jaw involved in its unfolding.
Yawning, a natural reflex
Yawning is a universal behavior common to all cash vertebrates, often perceived as a brief well-being. Stimulating concentration and alertness, yawning can have other functions. In humans, the social significance of yawning is a signal of tired or boredom of the interlocutor. This seems more of a conditioning psychosocial meaning that a physiological function. Excessive yawning can reveal pathologies neurological of tumor, vascular or epileptic origin. The taking antidepressants is the most common cause of excessive yawning. Finally, the yawn of replication, the one that we imitate when we see someone yawn, would be correlated with theempathy.
You will know all about yawning after reading this file and will finally be able to answer this famous question: why is yawning? contagious ?
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