We must begin with a definition of terms. Positive and negative reinforcement are two quadrants of operant conditioning. Positive reinforcement means adding (+) something a horse likes to make a behaviour more likely in future. This could be food or tactile rewards. Negative reinforcement means subtracting (-) something the horse doesn’t like to make a behaviour more likely in future. This is usually pressure, whether psychological or physical.
Among negative reinforcement trainers, there can be an attitude that reward is unnecessary.
Among positive reinforcement trainers, there can be an attitude that any pressure is bad.
Let’s analyze these two approaches and see if we can arrive at an optimal approach to horse training.
There is some research purporting to show that horses trained with positive (+) reinforcement have more optimistic affective states (mood) than horses trained with negative (-) reinforcement (Sankey et al, 2010). However, it must be remembered that during the shaping of a behaviour with positive reinforcement, reward must be withheld so the horse tries something more to achieve the next shaping criteria. This causes frustration, which is a pessimistic affective state. Also in the consolidation of a behaviour trained with positive reinforcement, reward must be moved onto a variable schedule, which can also induce frustration.
In the same study (Sankey et al, 2010), the positive reinforcement group of horses was taught to step back from the handler moving into the horse’s space. This is actually a fundamental example of negative reinforcement, in which the horse’s behaviour of stepping back removed the handler’s proximity. In this way, the study was not looking at ‘pure’ positive reinforcement, so the results cannot support the researchers’ hypothesis.
Indeed, a study of oxytocin levels in horses during foundation training using negative reinforcement found that as horses progressed through training, oxytocin levels increased, showing an increasingly optimistic affective state (Niittynen et al, 2022).
A more balanced view of the use of these two quadrants of operant conditioning, then, is clearly to make use of both. Positive reinforcement has the strength of being highly motivating for the horse especially when a learning task is difficult. Negative reinforcement has the strength of being predictable and controllable so that the horse experiences less frustration during training. A trainer who applies scientific knowledge of horse behaviour and learning, therefore, will be adept at applying both positive and negative reinforcement, which is known as combined reinforcement. In this way, the horse is always reinforced and often rewarded for correct behaviour, speeding up the rate of learning and creating an attachment between horse and trainer in the process. That special relationship between horse and human is, after all, what we are all looking for!
References:
Sankey, C., Richard-Yris, MA., Henry, S. et al. Reinforcement as a mediator of the perception of humans by horses (Equus caballus). Anim Cogn 13, 753–764 (2010). https://doi.org/10.1007/s10071-010-0326-9
Taru Niittynen, Veera Riihonen, Liza R. Moscovice and Sonja E. Koski, Acute changes in oxytocin predict behavioral responses to foundation training in horses, Applied Animal Behaviour Science, (2022) doi:https://doi.org/10.1016/j.applanim.2022.105707
Clairety Horsemanship 