Most horse people fall short of understanding calming behaviour that manifests as “calming signals”. Examples of these are yawning, scratching the face, lick and chew, and looking sleepy, among others.
We tend to interpret such signals through our own, human experience. Yawning, for example, is seen as a sign of relaxation, or “release” of stress. For humans, sure, but for horses, yawning represents uncertainty and stress. The yawn is an attempt to calm oneself in the face of unsettling events which can not be controlled by the horse.
Unlike humans, who yawn as a response to lowered oxygen levels in the blood (such as when our heart rate slows down at rest and we are tired), horses do not experience this. Wild horses rarely yawn, aside from right before they fall asleep, or just after they wake. When they do, it is to deal with stresses out of their control.
In captivity, we see yawning outside of sleep related activities and assume it means something else. Most likely, however, the yawns are a result of human activity that involves doing something to, or in the vicinity of, the horse. Something they find stressful and can not do anything to control or escape.
One such example is any kind of “body work”, such as chiropractic sessions or manual/mechanical massage. The horse tolerates this for a while, then, when there seems to be no end in sight, he starts to yawn to try and relieve some of the stress. His owners, or the people providing the body work, assume this means the horse is experiencing “release”, a pleasant sensation derived from the human’s activity and handling of the horse’s body.
This is clearly incorrect, a mere projection of the humans’ own expectations (“I am massaging the horse, I personally would feel great getting a massage, and would feel so relaxed I would be sleepy and yawning, therefore, the horse is experiencing the same thing, as evidenced by his yawning”).
This kind of misreading and misinterpretation is common.
Take “lick and chew” as another example. It is commonly believed by trainers and owners alike, that, in the wake of the horse learning something new, he stops to lick and chew as he processes the new information.
In reality, the horse is experiencing stress, usually as a result of pressure and release tactics. Once the pressure is released, the horse experiences a physical reaction to the relief from pressure: salivation. While under duress, the horse stops salivating. Once the scary, stressful event is over, salivation returns, and the horse licks and chews as his dry mouth is suddenly flooded with saliva again.
Similarly, a shut down horse (one who knows he can not escape what is happening, be it tacking up, body work, clipping, etc.) will look sleepy. This is often misinterpreted as “relaxed”. Sometimes, the horse truly is relaxed, while being handled in a gentle manner by a person he trusts. More often than not, however, they shut down when they know something unpleasant, and unescapable is about to happen (a dressage session with an unfriendly, painful bit comes to mind).
It is unfortunate we perpetuate our misunderstanding of these behaviours. We must learn to investigate them further, rather than just take other people’s word for it.
Of course a chiropractor or massage therapist will interpret the yawn as a good thing. They are invested in the belief that their actions upon the horse’s body are pleasant to the horse. But to the horse, they are an invasion of their personal space, sometimes an uncomfortable and painful one, depending on the situation.
How sad that, instead of responding to their calming signals with cessation of the activity in question, we push through, convinced our human interpretation of the same is the correct one, projecting our own feelings unto the horse, and passing on our “knowledge” to others who, in turn, become part of the problem.