If the rider practices patience in early training, the horse realizes the rider will not ask it to go into dangerous situations and it will lose its fear of objects. Size and position of the eyes and width of the head and body determine front and rear vision. Horses with large, wide-set eyes have more forward and rear vision than others. Even so, there are blind spots at both ends of the horse. This is why you should not approach a horse directly from the rear and why you should speak to the horse when passing behind it.
Frontal vision is affected by width of forehead and how the eyes are set in the head.
Most horses probably do not see objects nearer than three feet directly in front of their faces without moving their heads. With their heads in normal position, they do not see the feed they eat nor the ground they step on. Most riders discriminate against them. Allow your horse free rein in negotiating obstacles so it has good vision. Allow the horse to concentrate when traversing rough terrain, because it must remember the ground under its feet since it doesn't see it.