Goessler U R, Hein G, Sadick H, Maurer J T, Hörmann K, Verse T
Universitäts-Hals-Nasen-Ohren-Klinik Mannheim.
Laryngorhinootologie. 2005 May;84(5):345-51. doi: 10.1055/s-2005-861356.
Yawning is a physiological event that can be divided into three distinct phases: a long inspiratory phase, a brief acme and a rapid exspiration. The reason for yawning is not yet well defined. However this semi-voluntary event increases vigilance and aims to alert when drowsiness occurs. Yawning may have an important role for social communication. The neuropharmacology of yawning is complex and knowledge of its mechanisms is incomplete. While under the control of several neurotransmitters, yawning is largely affected by dopamine. Dopamine may activate oxytocin production in the paraventricular nucleus of the hypothalamus, oxytocin may then activate cholinergic neurotransmission in the hippocampus, and finally acetylcholine might induce yawning via the muscarinic receptors of the effectors. In fact, this scheme is simplified. Many other molecules can modulate yawning, such as nitric oxide, glutamate, GABA, serotonin, ACTH, MSH, sexual hormones and opium derivate peptides.
打哈欠是一种生理活动，可分为三个不同阶段：一个较长的吸气阶段、一个短暂的顶点阶段和一个快速的呼气阶段。打哈欠的原因尚未明确界定。然而，这种半自主的活动会提高警觉性，并旨在在困倦出现时发出警报。打哈欠可能在社交交流中发挥重要作用。打哈欠的神经药理学很复杂，对其机制的了解并不完整。虽然受多种神经递质的控制，但打哈欠在很大程度上受多巴胺影响。多巴胺可能会激活下丘脑室旁核中的催产素分泌，催产素随后可能会激活海马体中的胆碱能神经传递，最后乙酰胆碱可能会通过效应器的毒蕈碱受体诱导打哈欠。实际上，这个过程是简化了的。许多其他分子也可以调节打哈欠，如一氧化氮、谷氨酸、γ-氨基丁酸、血清素、促肾上腺皮质激素、促黑素、性激素和阿片衍生肽。
