Zívání

Zívání, also known as yawning, is an involuntary reflex characterized by a deep inhalation, opening the mouth wide, and then exhaling. While the exact function of yawning is not fully understood, several theories exist. One prominent hypothesis suggests that yawning serves to regulate brain temperature. The deep inhalation and subsequent exhalation might help to cool down the brain when it becomes too warm. Another theory proposes that yawning increases alertness and arousal, particularly during periods of drowsiness or boredom. It is thought that the stretching of facial muscles and the deep breaths associated with yawning may stimulate the brain and improve attention.

Yawning is a contagious behavior, meaning that seeing or hearing someone else yawn can often trigger a yawn in the observer. This contagiousness is more pronounced in humans and is thought to be linked to empathy and social bonding. Studies have shown that children and individuals with stronger empathic abilities are more susceptible to contagious yawning. While often associated with tiredness, yawning can occur in various situations, including boredom, stress, hunger, and even as a response to seeing others yawn. It is a common phenomenon across many species, including primates, birds, and even some reptiles, suggesting an evolutionary basis for the behavior.