In a recent review of equine learning behaviour, researchers Jack Murphy and Sean Arkins of the Department of Life Sciences, University of Limerick, Ireland, noted that where equines are concerned, “training is actually enhanced when the training methods employed exactly match the mental ability of the horse.” Although the statement seems elementary, matching training methods with a horse’s cognitive capacity is central to maintaining a balanced social interaction between horse and human, and arguably more challenging than it might first appear.

We train our horses based on assumptions about their cognitive ability founded more on tradition, experience, and folklore than on science. Yet, when we turn to science for answers, controlled experiments about equine cognition do not easily translate meaningfully into our everyday practice with horses. Does a horse’s ability to choose the largest triangle in a lab experiment tell us anything about his understanding of being the fastest clean horse in a jump-off, or executing a stunning half-pass? My goal in this article is to bridge this gap, explore what we know about how horses think, and extract from these studies some of the implications and applications for our day-to-day human/horse interactions.

Help with Memory: Concepts and categories

Many equine cognition studies rely on positive reinforcement to teach horses to make particular choices among two or more alternatives. Horses may be rewarded for always choosing the largest object, and are considered to have grasped the concept “largest” when they can apply this rule to a novel set of objects. Concept studies tap into higher-order cognitive abilities because the animal must understand the common characteristics shared among two or more objects that place them in the same category and as distinct from alternatives. This sophisticated problem-solving also provides a more efficient mechanism for recall. Rather than having to remember each target object on each trial, the horse need only remember the overriding rule that describes that concept.

Equine researchers Evelyn Hanggi and Jerry Ingersoll of the Equine Research Foundation in Aptos, CA, trained horses to learn particular concepts such as larger vs. smaller, or open shape vs. solid. Horses quickly and reliably learned the concepts and were able to remember them seven and even 10 years later, without practice in between, and with no deterioration in performance. They were also able to apply their knowledge to new tasks, and use the same rules to choose the correct target object.

Hanggi’s research unravels a small piece of the puzzle of equine cognition, but it does not tell us whether horses’ categories bear any resemblance to our own. For a horse negotiating his way in a herd, the category of aggressive vs. friendly may be infinitely more relevant than bay vs. chestnut, for instance. Hanggi’s research also highlights that both positive and negative learning experiences have staying power. As she comments, “What horses learn, they remember for a very long time, and what happens during training stays with them long enough to either benefit or hinder the process.”

What horses know about horses

Studies have indicated that horses have quite sophisticated social cognition, i.e. the receiving, storage, retrieval, and processing of information about members of the same species. Horses in a social unit need to not only recognize individual members, but understand the relative ranks and relationships among them, distinguish friends from foes, predict how others might act, and remember this information over the short and long term. Studies of feral horses by Claudia Feh of the Association pour le cheval de Przewalski in Arles, France, have revealed that even after a one-year separation, stallions were able to immediately recognize and separate out their mares from a much larger herd of mares.

A related question is whether horses understand and respond to social networks from auditory information alone. At the University of Rennes, France, in 2009, A. Lemasson and colleagues filmed the behavioural responses of 30 horses while they heard audio recordings of horses from their immediate social group, a neighbouring group, and from unfamiliar horses. Horses were reliably able to distinguish the different groups, showed increased efforts to move toward the calls of their own group members, and demonstrated heightened alertness when hearing unfamiliar whinnies. These findings suggest that horses can learn vocal signatures, create mental representations of their social network, and adjust their behaviour according to the familiarity and status of the caller.

What horses know about humans

Horses are also adept at transferring their social cognition skills to another species. There seems to be good evidence that they are surprisingly skilled at telling us apart and remembering us for a long time, even without contact between encounters. Sherril Stone of Oklahoma State University in Tulsa found that horses could be reliably trained to discriminate between photographs of a particular person’s face vs. her sister, and the more challenging task of a person vs. her identical twin sister. The identical twin discrimination actually ran counter to the author’s predictions. Apparently, horses are better than humans at differentiating identical twins! Furthermore, the horses were able to apply this information to a real world setting, spending more time with and offering more nuzzling behaviours towards the person whose photograph had been consistently associated with a food reward.

Research also suggests that horses are able to identify us by our voice alone. A team of British researchers led by Leanne Proops at the University of Sussex tested 72 horses who heard an audio recording of their name being called by either a familiar or unfamiliar person, while the same two people stood in front of the horse. Horses consistently matched the voice to the correct person, focusing their attention on the person whose voice was being played. Horses were also able to make the correct voice-to-person match when both people were familiar.

These findings are particularly surprising given horses’ emphasis on visual body language cues rather than verbal communication. Given this bias, the horse’s ability to recognize and relate to human voices highlights their amazing social adaptability in working with humans.

Positive vs. Negative Reinforcement

Other research suggests that horses learn to make discriminations rapidly and remember them for months or potentially longer. Carol Sankey and her research team at the University of Rennes, France, taught 21 ponies a learning task – to back-up in hand – using either positive reinforcement (PR) or negative reinforcement (NR) over five training trials of one to three minutes each. All ponies learned the task within the allotted training period. Although there were no differences in baseline measures between the two groups before training, PR ponies learned the task more quickly, exhibited more positive reactions toward their handlers during training, including eight months later, with no further interaction in between testing. These ponies were also more likely to respond favourably toward unfamiliar individuals than were NR ponies.

The ponies’ stress levels also differed between the groups. Baseline heart rates were similar for PR and NR ponies on the first day, and remained stable for the PR ponies throughout the experiment. NR ponies had consistently higher heart rates from the second day on, which soared even before each training session began.

These results are relevant for our current approach to horse training, which is almost entirely dependent upon negative reinforcement. Negative reinforcement (not to be confused with punishment) involves applying an unpleasant or mildly aversive stimulus (such as leg pressure) and ending it when the horse performs the desired behaviour (moving forward). In working with horses under saddle, this pressure-and-release system is practical, where positive reinforcement – offering the horse a food reward for a desired behaviour – often is not. However, Sankey’s research suggests that there may well be more room for introducing positive reinforcement when working with horses on the ground that could enhance the owner/horse relationship both in the short and long term. It is also noteworthy that the total training time for Sankey’s ponies was 15 minutes or less, and yet the task and interaction was retained for months. This can be a real advantage when human/horse interactions are positive and a very real disadvantage when they are not!

Do horses read our gestures?

This burgeoning field in animal research indicates that dogs are highly skilled at using human gestures, gaze, and attention to locate a hidden food reward, where chimpanzees, wolves, and most other species tested to date are not. These studies suggest that dogs have evolved an ability to understand human intentions, quite unique from other animals (see Brian Hare and Vanessa Wood’s fascinating book “The Genius of Dogs” for a full discussion).

Equine studies have had mixed results. A 2011 study by Konstanze Krueger and associates found that horses were able to choose the correct bucket of food among three alternatives when a target person stood behind the bucket, but performance declined when the person moved away from, but gazed at, the bucket. Horses have also chosen correctly when someone tapped the bucket’s side (Proops et al, 2009), although their success may have had more to do with prior associations of bucket sounds and food rewards than a real understanding of what was being conveyed by this human gesture. When instruction is given by an owner or caretaker, rather than an unfamiliar individual, horses make more correct choices, again suggesting that they may be responding more to socialization cues, rather than exhibiting a true understanding of human intention.

These studies highlight horses’ very real limitations in understanding our intentions, perceptions, and perspectives, even when those intentions are focused on an obvious benefit for the horse, such as indicating a food source. When intentions are focused for human benefit (as is true for most of our horse/human interactions), the horse’s insight may be yet more compromised. With clear, unambiguous signals of positive and negative reinforcement, horses come to understand the response behaviours we want. Is unlikely that they understand our “larger picture” intentions, or share our goals and desires. Research looking into “theory of mind” tackles this question specifically.

Do horses know what we are thinking?

“Theory of mind” is a psychological construct that describes one’s ability to understand the thoughts, intentions, and perceptions of others and to recognize that others have mental states that differ from one’s own. Researchers generally agree that children do not have theory of mind until age four, and that some children on the autism spectrum may always struggle with this construct. Theory of mind has not been reliably tested in animals, as studies rely on interviews where participants are asked about their thought processes.

However, self-awareness, considered a necessary precursor to theory of mind, has been studied extensively. Using mirror recognition as a measure of self-awareness, research indicates that some, but not all, great apes, dolphins, orcas, and elephants show self-recognition. Although horses have not been tested, animals who are genetically more similar to humans such as monkeys do not pass mirror recognition tests.

Without self-awareness, you are not able to use use your own experience to infer the mental states of others, and are not able to take into account what other individuals may know, want, or intend to do. Theory of mind is relevant to horse training, because owners and professionals often overestimate what horses understand about our intentions and goals. Horses do not behave well because they are brave, loyal, or want to please us, or misbehave because they are malevolent, lazy, or spiteful. It is more likely that horses operate in terms of immediate consequences. They do what works, and stop doing what does not work. The onus lies with us to determine how an unwanted behaviour is working for our horse, and make it stop working. Similarly, we need to maintain desired behaviours by ensuring that they continue to have benefit for our horses.

Cognitive Conclusions

Horses’ highly social nature and their propensity to form lasting relationships, even across species, have made them highly trainable and thus ideal candidates as sport horses. This trainability allows us to use increasingly subtle aids that translate into the varied and remarkable disciplines of our sport. It also brings with it a responsibility. As Paul McGreevy and Andrew McLean, two leading Australian equine scientists, note: “Just because we are not intending to train a response does not mean that the horse will not be learning something. Horses are learning all the time, since they make no distinction between associations built through regular handling, regular riding, training, and competition.”

Having a better understanding of horse’s cognitive capacity has very real implications for training methods, and owners and trainers need to be knowledgeable and realistic about what is within and outside a horse’s cognitive grasp. Indeed, we do a disservice to our horses by both underestimating and overestimating their cognitive capacities.

Antonia Henderson is a psychology professor at Vancouver’s Langara College, and also a research and equine psychologist – teaching, consulting, and writing about the psychology of human/animal relationships.