Yawning is a physiological behavior, an emotional stereotypy that indicates the homeostatic process of the mechanisms regulating rhythms, such as sleeping/waking, hunger/satiety or mating/relaxation, generated by the diencephalon. As with all physiological behaviors, its deregulation reveals disorders. In daily practice, yawning as a symptom is generally neglected. That is why we propose a wide...

Yawning has been rarely described in association with seizures and not previously documented by video-EEG. We present a 48-year-old woman with a long history of non-dominant for speech hemisphere seizures and post-ictal yawning. Yawning was irresistible, forceful and often repetitive. We reviewed the few similar epileptic cases described in the literature and discussed the possible mechanisms. ...

Recent evidence suggests that yawning is a thermoregulatory behavior. To explore this possibility further, the frequency of contagious yawning in humans was measured while outdoors in a desert climate in the United States during two distinct temperature ranges and seasons (winter: 22°C; early summer: 37°C). As predicted, the proportion of pedestrians who yawned in response to seeing pictures of...

Young male albino rats yawn significantly more than females or castrated males when injected with physostigmine (0.10 mg/kg). Treatment with testosterone (100 micrograms daily) during seven days restores cholinomimetically induced yawning in castrated males, and increases yawning in normal and androgenized females. Treatment with estradiol (200 micrograms daily) during one week does not modify ...

Almost all the vertebrates yawn, testifying the phylogenetic old origins of this behavior. Correlatively speaking, yawning shows an ontogenical precociousness since it occurs as early as 12 weeks after conception and remains relatively unchanged throughout life. Thus, it is contended that these common characteristics and their diencephalic origin allow to model an approach from which emerges a ...

Dopamine D(2)-like agonists induce penile erection (PE) and yawning in a variety of species, effects that have been suggested recently to be specifically mediated by the D(4) and D(3) receptors, respectively. The current studies were aimed at characterizing a series of D(2), D(3), and D(4) agonists with respect to their capacity to induce PE and yawning in the rat and the proerectile effects of...

Yawn contagion in humans has been proposed to be related to our capacity for empathy. It is presently unclear whether this capacity is uniquely human or shared with other primates, especially monkeys. Here, we show that in gelada baboons (Theropithecus gelada) yawning is contagious between individuals, especially those that are socially close, i.e., the contagiousness of yawning correlated with...

In this study the effect of adrenergic receptor agonists and antagonists on physostigmine induced yawning was investigated. Intraperitoneal injection of different doses of physostigmine (0.03, 0.05, 0.1 and 0.2 mg/kg) caused yawning in white rats. The greatest response was seen at a dose of 0.2 mg/kg physostigmine. Phenylephrine, an α1 agonist, and clonidine, an α2 agonist, led to a decrease in...

Yawning is a clinical sign of the activity of various supra- and infratentorial brain regions including the putative brainstem motor pattern, hypothalamic paraventricular nucleus, probably the insula and limbic structures that are interconnected via a fiber network. This interaction can be seen in analogy to other cerebral functions arising from a network or zone such as language. Within this n...