It can help muscles and joints function better, and its absence can be a marker of brain injury. This powerful action can also be replicated for stress-reduction and therapy.
It’s possible you’re already yawning, or at least have a yearning for it. No doubt you’re thinking about it, so give it time.
Yawning, like sneezing, swallowing, hiccups and other reflexive phenomena, is perfectly natural, commonly done daily by all mammals, and is a necessary function. While we can often encourage a yawn, public yawning is considered taboo in some cultures, or embarrassing in others, and voluntarily inhibiting it is difficult. At the same time, we should be thankful for this natural reflex.
Yawning seems like a simple phenomenon, yet it is associated with many brain and spinal cord areas. It is also linked to various neurotransmitters, like dopamine and serotonin, along with sex hormones and many others, not to mention many key muscles that control full body posture, movement and balance.
As a form of body pandiculation, yawning can activate many muscles and other soft tissues, various joints, along with structures in the sinus, ears, nose and throat. While socially it sometimes is taken as a sign of boredom, it’s actually an arousal response by the brain, most noticeable upon awakening. Sure, that meeting may be boring, but yawning may be the brain’s attempt to be more alert and increase attentiveness, by changing consciousness and accelerating brainwaves, or increasing oxygenation.
Yawning can positively affect the flow of cerebrospinal fluid that bathes the brain and spinal cord. This in turn can influence various natural chemicals associated with the circadian sleep-wake cycle. It also enlists the respiratory system, cervical spine and related muscles.
Some features of yawning include:
- Social/behavioral aspects — a yawn can be initiated by seeing, hearing, reading, or thinking about it. This can be triggered by the brain’s mirror neurons that can initiate a yawn, the reason it’s called contagious.
- Yawn contagion is significantly affected by the social and/or emotional bond between individuals, including family.
With all these positive associations with yawning, when it doesn’t happen it could indicate potential problems. As a normal physiological behavior, deregulated yawning — much more than normal, or little to none — may be indicative of an underlying disorder, including excess stress and autonomic nervous system dysfunction. In particular:
- Reduced or absent yawning may be indicative of overtraining or burnout.
- Yawning may be absent or impaired in those on the autism spectrum, or other brain injury, such as Parkinson’s disease or schizophrenia.
- Reduced, restricted, or lack of yawning, or when accompanied by pain, may indicate TMJ (cranio- or temporomandibular joint) dysfunction. Yawning can occasionally cause a dislocation of the jaw joints.
- Frequent and repeated yawning can indicate sleep impairment. and especially may be related to impaired driving and the increased risk of a crash.
- Medications, including antidepressants, can increase the prevalence of yawning, and may increase during detoxification from caffeine and opiates.
- Excessive yawning may be associated with gut dysfunction (as an autonomic imbalance).
- Uncontrollable yawning can be seen in meningitis, and in cases of brain tumors.
Another important healthy role for yawning is pressure equalization. The ear’s eustachian tubes are important in aerating the middle ear. But variations in pressure during air travel, diving, or changing altitude when running, biking or driving can interfere with these actions, and yawning can be the remedy.
Also, for vocalists or those using their voice a lot, yawning helps open the glottis and better position or lower the larynx to minimize muscular effort when using the voice.
Other physiological aspects of yawning can be useful as therapy, such as for anxiety states, relaxation, insomnia, or as an anti-stress aid. Yawning has a proprioceptive rehab effect on the whole body due to the various muscle contractions and relations, especially for the jaw muscles, associated with the action.
Have you yawned yet? Don’t hold it back.
Bertolucci LF. Pandiculation: nature’s way of maintaining the functional integrity of the myofascial system? Bodyw Mov Ther. 2011;15(3). doi: 10.1016/j.jbmt.2010.12.006.
Kuć J, et al. Smiling, Yawning, Jaw Functional Limitations and Oral Behaviors With Respect to General Health Status in Patients With Temporomandibular Disorder-Myofascial Pain With Referral. Front Neurol. 2021;12:646293. doi: 10.3389/fneur.2021.646293.
Walusinski O. How yawning switches the default-mode network to the attentional network by activating the cerebrospinal fluid flow. Clin Anat. 2014;27(2). doi: 10.1002/ca.22280.