Dr. Robert Miller from California is one of the most respected and famous equine veterinarians in the world, and he recently spoke about understanding the horse’s mind.  In DVM 360, he says that all equine behaviors are related to the first behavior, and that is “flight is life.”  The horse’s survival behavior is flight as the horse has no weapons like horns and escapes predators by running away.  Humans, on the other hand, are predators and so we have to understand how the horse views the world to understand their mind.  The horse is the most perceptive of all domestic animals because if they are going to stay alive in the wild, they have to know when to run. 

Horses are very sensitive and can feel the rider’s slight change in position or weight shift, and they have 360 degrees of vision by turning their nose only about an inch, so they always know what is going on behind them.  However, their depth perception is not very good, so stepping up into a trailer or crossing a creek is scary until they are familiar with the process.  And while lightening quick responses allow them to stay alive, they can also cause injuries to humans that are not being careful and in the wrong place.  Dr. Miller also says that horses are the easiest domestic animal to desensitize to frightening by non-painful stimuli. If the training is done correctly, they can be trained to not be frightened by loud sounds or scary scenes.  They also learn quickly but they can learn the wrong thing just as quickly as the right thing; plus, they have a long-term memory so if something happens to them in a certain situation, they don’t forget it.  If their heads are down and they're smacking their lips, they are indicating submission and trust but if the head is up, they are thinking “I am afraid and need to run away.”