Sorry, not trying to be nitpicky, but negative punishment means that you’re taking away a favorable/pleasant stimulus in order to reduce an undesirable behavior. The above is an example of negative reinforcement, which is the removal of an aversive stimulus to increase a desired behavior. The aversive stimulus would be the hand and body movement, and the horse moves away from it to make it stop.
I’m not sure if you’ve ever tried positive reinforcement, but if you do you might realize that this is actually not true. The learning process can be fun and exciting for the learner.
However, I’m also not saying that a horse’s life should never involve any amount of stress or fear. The point is just that when you are training, you don’t have to incorporate stress and fear into the process in order for the animal to learn - and it is in fact counterproductive. No animal is learning when they’re under stress. I’ll repost the great snippet that @scislandsprite posted earlier in the thread:
When Praise is Not Enough
If your horse has some very bad habits, and words of encouragement are not enough to set a platform for a friendly working relationship, then it goes without saying that you have to be firm. You might even have to sharply reprimand your horse to get his attention, stop the behavior and show him who’s in charge.
This brings up an important point regarding the prefrontal cortex and the dopamine reward system: Once you have completed the necessary correction, your horse’s brain is now in a fear-based mode. Although he initially acts more alert and becomes more obedient, this occurs at a cost to his intelligence. With his recent mistake at the center of his attention, he becomes more fearful and concerned about the events that just transpired. At this point, he is not in a position to learn anything. Fear can stop a mistake, but it will not help him learn an alternative form of behavior and, most importantly, develop an intimate, respectful bond with you, the rider.
Here’s the brain science behind the process: After a harsh reprimand, the horse’s prefrontal cortex gets turned off and the amygdala, the fear center, takes over. Since the prefrontal cortex is crucial for developing a sense of self as well as motivation, intelligence, creativity, alertness and learning, having it shut down is problematic. With the prefrontal-cortex function impaired, the amygdala gets activated. This smaller, almond-shaped group of cells is programmed to respond to any unpredictable or dangerous experience by preparing for flight or fight. So, when a horse goes into fear mode and the amygdala is turned on, he becomes temporarily more alert, but less intelligent and less able to learn.