Equine Wiring Diagram.
Recent advanced clinical and field research by
Peters and Black, facilitated by technology such as functional MRIs for scanning brain activity, have provided a pretty clear "wiring diagram" as to how a horse's brain operates. These findings have validated some theories regarding horse behavior and learning, and have also debunked a few myths. Understanding how a horse processes its world is key to understanding how to shape a horse's response to potentially disturbing stimuli and in turn improve responses to the rider's reassurance and cues.
The main circuitry that processes input and generates response behavior involves special nerve structures called dendrites. In short, dendrites are extensions of nerve cells that receive and transmit information to adjacent nerve cells. Some dendrites are DNA designed, but most are developed, along with the behaviors that they trigger, as a result of the horse's experiences.
Horses are prey animals. To survive in the wild they don't have the luxury of stopping to mull over a threat and choose the best option. In an environment containing predators and other threats, they have to execute an immediate "if - then" response.
We as handlers and riders have the ability to modify horses' behavior to a significant degree, and there are hundreds of theories out there as to how to do this. However it all boils down to how we alter those dendrites, that adaptable "hard wiring" inside our horse's brain.
You wouldn't attempt to rewire an airplane without first understanding the circuitry, so why would you want to do so with a horse? Perhaps only because the horse travels closer to the ground.