On this page:

Operant conditioning

basic theory

in nature

in animal training

in horsemanship



The basic theory

Operant conditioning is a type of learning whereby a behavior is modified by its consequences. The consequences may be of two kinds: reinforcement and punishment.

Reinforcement is a kind of consequence that increases the likelihood of a given behavior. Punishment is a kind of consequence that decreases the likelihood of a given behavior.

Both kinds of consequences may result from adding or removing a stimulus from the animal's environment. The terms "positive" and "negative" are applied, respectively, to adding or removing something from the animal's environment. This gives us the so-called four quadrants of operant conditioning:

  • Positive reinforcement:
    • A pleasant stimulus is added to the animal's environment when a behavior occurs, resulting in an increased chance of the animal repeating the behavior.
  • Negative reinforcement:
    • An unpleasant stimulus is removed from the animal's environment when a behavior occurs, resulting in an increased chance of the animal repeating the behavior.
  • Positive punishment:
    • An unpleasant stimulus is added to the animal's environment when a behavior occurs, resulting in a decreased chance of the animal repeating the behavior.
  • Negative punishment:
    • A pleasant stimulus is removed from the animal's environment when a behavior occurs, resulting in a decreased chance of the animal repeating the behavior.

Pleasant or unpleasant stimuli are "in the eye of the beholder". What one animal may perceive as pleasurable may constitute an aversive (unpleasant) stimulus to another animal. Consider a horse checking out the spray from the hose that you are holding. One horse may feel the spray, jump back, and subsequently avoid the hose: this stimulus was aversive to him. Another horse may engage with the spray, paw at it, expose different parts of his body to it, and will subsequently come for more whenever you turn on the hose: he finds this stimulus pleasurable!

Operant conditioning in nature

Four quadrants of operant conditioning are not artificial concepts invented in laboratory; one can observe them in everyday natural behavior of animals.

horses grooming each other

Mutual grooming is an example of positive reinforcement: both horses engaged in mutual grooming positively reinforce each other for this behavior; at the same time, both are being positively reinforced. Quite a win-win situation for both parties!




Another example of positive reinforcement: two horses engaging in play. They keep nipping at each other's faces until one of the partners rears up. Some mock sparring follows, until one of the horses runs and the other gives chase. Then the partners face each other and the cycle repeats. This horseplay may seem rather violent to us, but both horses engage in it over and over again. The playmate's reactions are reinforcing to both horses.

horses soliciting play horses engaging in play horses rearing in play

A more complicated example of reinforcement: a horse engaged in the play of chasing a goose. The sequence of photos below shows a horse trotting up to a Canada goose that had been quietly foraging in the field, lunging at the unsuspecting bird with his ears pinned in a threat display, giving chase, and finally letting the goose escape unharmed. This behavior is open to interpretations. Was the horse viewing the goose as an unpleasant stimulus which his aggressive behavior removed from his environment (negative reinforcement)? It could be so. However, watching this scene gave me a distinct impression that the horse was having fun, and the stimulus "running goose" created by threatening and chasing a "stationary goose", was a great fun toy and an immensely pleasurable addition to his environment! What about the goose's side of the story? Clearly, it was negatively reinforced for a rapid escape. Conversely, it was positively punished for foraging near a belligerent equine!

horse trotting to a goose horse threatening goose horse threatening goose horse chasing goose

horse chasing goose horse chasing goose horse and goose end of chase


horse sniffing a newcomer

Most social interactions are example of a complex interplay of all four quadrants of operant conditioning, as illustrated by the photos on the left.

The spotted horse is a newcomer. He and the bay horse are engaged in head-to-tail sniffing, as the grullo horse hangs out nearby.



horses run from an aggressive horseThe bay horse rears up, causing the newcomer and the grullo to flee. His aggression is reinforced by their dramatic escape. As far as the grullo and the spotted horse, they will be less likely to come close to or engage in social activities with the aggressor, who had punished them for being near him and reinforced them for increasing their distance from him.


Operant conditioning in animal training

Operant conditioning is widely used in animal training. Think about the proverbial carrot and stick! There are numerous methods of training domesticated animals that utilize negative reinforcement and positive punishment in the form of physical corrections, and positive reinforcement in the form of petting, praise, and food rewards.

In most training methods, negative reinforcement is the main tool for obtaining the desired behavior. Positive punishment and positive reinforcement play a secondary role. A modern addition to the arsenal of an animal trainer, clicker training differs from other training methods in that it uses positive reinforcement to obtain and maintain behaviors, with other quadrants of operant conditioning playing a secondary role.

Operant conditioning in horsemanship

The history of horse training abounds with compulsion, as evidenced by harsh bits, spurs, and other equipment from early cultures up to modern days. However, since ancient times, the most renowned horsemen, whose names went down in history, were aware, and warned against, the excessive force and punishment. Xenophon, a 4th century BC Greek horseman and military commander, left us this moving passage:

“For, as Simon also remarks, what the horse has to do under compulsion, he does not understand. Such actions are not beautiful, any more than if one were to teach a dancer by whipping and spurring. For there is apt to be far more ugliness than grace about the actions of either a horse or a man who is subjected to such treatment. But the horse must follow the indication of the aids to display of his own free will all the more beautiful and brilliant qualities.”*

Writes a modern day master, Nuño Oliveira:

“Equestrian art is the perfect understanding between the rider and his horse. This harmony allows the horse to work without any contraction in his joints or in his muscles, permitting him to carry out all the movements with mental and physical enjoyment as well as with suppleness and rhythm. The horse is then a partner, rather than a slave who is enforced to obey a rigid master by constraint.”**

What these horsemen advocate is, essentially, the judicious and humane use of negative reinforcement. closeup of Western rider's legcloseup of an English rider's legNegative reinforcement in the form of mild physical pressure is the foundation of riding aids. We all admire masterful riders for their light aids, and many of us enjoy dancing with a partner. In both cases, negative reinforcement is used to guide the partner, be it equine or human.

Negative reinforcement in the form of application and release of mild pressure is the main tool for obtaining desired behaviors in horse training, be it ground work or riding. Positive reinforcement is intuitively used by every horse person who praises, pets, or gives horse a treat after a good work session or a particularly well performed move.

Clicker training, as applied to horsemanship, uses high value positive reinforcement, such as food, as the primary training tool. Positive reinforcement may be used by itself to shape behaviors freely offered by the horse, or in combination with more traditional pressure and release.

*Xenophon, On Equitation, in Anderson, J. K., Ancient Greek Horsemanship, University of California Press, Berkeley and Los Angeles, 1961, pp 155-180.

**Oliveira, N., Reflections on Equestrian Art, second edition, J.A. Allen, London, 1988



 back to top of page