Horse Brain, Human Brain. Janet Jones
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the goal for composure at 45 feet. If you’re rushed (“I’ve got an appointment!”) or you’re annoyed (“You’ve seen that thing a million times!”), start the lesson another day. Forcing horses is a good way to destroy their trust in you, frighten them all the more, and wake up with Nurse Ratched beside your bed.
Within 10 minutes of this exercise, Hawkeye was walking, trotting, and cantering past the light sliver without looking at or bending away from it. She was relaxed and calm, with no struggle between horse and rider. But it’s not always that easy.
My Horse Is Still Scared
Suppose you try this exercise, but your little knucklehead is still freaking out. Here you revert to groundwork. Ride to a spot he considers relatively safe. Dismount and immediately put him to work. If necessary, longe him to get his mind off the problem. Test his progress by gradually moving the longeing circle so that the fright-sight is closer to the horse’s side.
Now slow to a walk, remove the longe line, and try leading the horse in the same loops you used before, at the closest distance he considers safe. Give him a chance to discover that the patch does not bite. If necessary, use some vicarious learning: Let him watch a familiar human friend walk to the object, stand next to it, and speak calmly. Stroke his neck and encourage him to approach from the side. A step or two more than the horse wants equals success. Offer praise and stop for today.
If the horse is so deep into his fraidy-hole that this technique fails, have your friend bring a known, preferably dominant horse to the object the next day. (Verify ahead of time that this horse is unafraid.) Speak slowly and stroke your horse’s neck while he watches his buddy survive the terror. If this also fails, move out of sight of the object and put your horse to work on a completely unrelated task. Tomorrow, start building his trust using objects that he considers less frightening. Eventually, he will be calm enough to return to the original fright-sight and try again.
When your horse is finally relaxed enough to advance face-first, let him stretch down and forward for a good sniff. He’ll probably startle a couple of times—that’s okay, you’d jump too if you had to sniff a tarantula in your blind spot. Touch the hazard so your hand makes a soft noise against it; this will allow the horse to learn more through his ears. Gently roll or push the object around as the horse becomes accustomed. It’s important to wait for this frontal approach until the horse is completely relaxed while approaching from the side and standing next to the object.
Peripheral Motion
The back of an eye—horse or human—contains 55 different types of cells specialized for vision. But relax, we only need to discuss two: rods and cones. Stop reading for a minute and look at a scene. Anything: your living room, a view out the window, your hand, whatever. Every pixel of light or dark that you see in that scene is transmitted through your rods and cones. Each cell corresponds to a tiny part of the visual scene, and if that part of the scene is bright, its rod or cone sends a signal to your brain. If another minute piece of the scene is dark, the rod or cone corresponding to it stays mum. Every part of the visual scene is coded by 210 million rods and cones in the human eye, until your brain contains a neural pattern of light and dark that represents the entire view. Every time you move your eyes, your rods and cones transmit a new set of signals. Pretty cool, huh?
Rods are especially good at picking up off-center motion in poor light. They do not transmit detail. Equine eyes are loaded with rods, and rods are connected to cells that send information about motion on a fast track to the brain. This combination gives horses an extraordinary ability to notice tiny rapid movements. If we had a horse’s rods, we’d shy all the time at the countless zips of motion flying through our view. Riders often complain that their horses are “shying at nothing”—in fact, they are shying at very real sights that we have too few rods to sense. What’s truly remarkable is that horses don’t shy more and that they allow us to modify the behavior at all.
So, rods and cones transmit a scene’s pattern of light and dark to the brain. The human brain then takes half a second to process each glance at the world and determine what it has seen—shape, color, size, distance, meaning, importance, and so on. Half a second of processing is out of the question for a horse in the wild: He needs to notice the faintest wave of the grasses and step on the gas. If the movement turns out to be a bicycle instead of a lion, that’s okay. Little is lost by running from a bicycle.
By nature, the horse relies on peripheral motion vision for safety. It dictates his need to startle or bolt—and otherwise “misbehave”—while ridden. Help him out by sharpening your own peripheral senses. Try to become more aware of objects behind and to the sides of your eye, putting your ears, nose, and knowledge to work. Begin to notice with your body where your horse is looking—it’s an intuitive skill that develops with attention and practice. If horses are all jacked up in an area where they’re normally calm, investigate. Chances are good that they notice something you do not and are trying to tell you about it.
Blind Spots
Despite its horizontal band of panoramic vision, equine eyesight includes a number of blind spots. Without changing position, the horse cannot see above his neck or back, beneath his belly or neck, or directly behind him. The sharp acuity needed to inspect or identify objects is best in a horizontal streak at the horse’s eye level, due to the distribution of rods and cones in the eye. So nearby dogs or children on the ground, or balloons and birds above eye level, are hard for the horse to spot until they move.
The area to the outer sides of the horse’s back legs is only barely seen. Surprised from behind, even the sweetest horse can kick in any direction, causing severe harm or death. That’s why we approach a horse’s hindquarters from the shoulder, moving back while speaking, standing close, and touching his side. Lesson number one to new riders is never to walk up behind a horse.
Another blind spot exists in front of the horse’s face, from eye level to the ground below his nose and out to about six feet. A hand suddenly raised in this area appears to come from nowhere. Horses cannot see the grass they eat, the bit they accept, the fingers that stroke their muzzles, or the ill-supervised child who stretches up to kiss their soft noses. Instead, they use their long mouth whiskers to sense this area. A horse whose whiskers are shaved is at a sensory disadvantage.
Finally, there’s a blind spot inside the equine eye that projects onto the visual scene when horses move. All those cells at the back of the eye transmit their signals along the optic nerve to the brain. To carry them, the optic nerve has to connect to each eye, and where it connects, rods and cones cannot exist. This location is called the optic disk (fig. 3.5). It occludes sensory receptors just like a manhole cover hides the drain below a street.
3.5 The optic nerve creates an internal blind spot where it exits the human and equine eye. Cells at the optic disk cannot sense visual information from that part of a scene.
When the head and eyes remain still, the visual area of the world that corresponds to the optic disk becomes invisible. This is true for people and horses—although the equine optic disk and its corresponding blind spot are larger than ours. In daily life, we move our heads and eyes around to solve this problem. Human brains also fill in the blind spot by imagining objects that must be there even though our eyes can’t see them.
If you find the blind spot in your eye, it will be easier to understand the blind spot in your horse’s eye. Take a look at figure 3.6. Hold the book up so that the cross is in front of your left eye. Close your right eye and stare at the cross with your left eye. Without moving your left eye, begin to notice the outer periphery of your vision so that the black circle is visible. Now move the book in and out slowly—closer and farther from you. When the book is 4 to 12 inches from your left eye, the circle will disappear. That’s your blind spot! When you find it, make tiny movements with the book so the circle falls into and out of the blind spot. It will vanish then reappear.
3.6 Find your blind spot. (Please see text for instructions.)
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