Feb 282010
 

With my toddler’s second birthday fast approaching, the subject of boundaries is close to my heart. The “just you wait until….” brigade has been out in strength, warning me of the need to enforce boundaries before my toddler turns into a monster. Funnily enough, different people with the same message gave me similar warnings about my horse when I decided to take more of a positive approach to his training. I am still waiting for him to turn into a monster – did I just get lucky? Could I get lucky again? Or could I just be doing something right?

We tend to think of setting boundaries as rigid rules which must never be broken. We are horrified if we find ourselves in the situation where our horse or child is testing the boundaries. What should we do about it? Is it a dominance issue? How can we re-enforce the boundaries ethically (missing the irony in trying to “force” anything ethically)? What will people think? How will we cope?

Perhaps the last two questions are the key to the issue. We rarely stop to consider why we have set those boundaries. Of course, we tell ourselves that it is for the good of our horse/child but very often there are other reasons, perhaps more subconscious. We are terrified of what people might think and we are terrified of the unknown. But suppose, just suppose, that the real question we should be asking ourselves is “are my boundaries reasonable?” If the horse/child in question thinks not then we have a whole new world to explore.

The only writer I have seen delve into this thorny subject is Alfie Kohn, author of “Unconditional Parenting”, which I would recommend to anyone with children and also to anyone with an interest in the use of non-manipulative positive reinforcement with animals. It is a wonderfully challenging book which really got me thinking about how we can use positive reinforcement to enhance the personality of the horse/child, instead of just trying to achieve certain behaviours for our own advantage. One of his “principles of unconditional parenting” is to consider whether or not we are making a reasonable request of the child:

“Here’s a very unsettling possibility: Perhaps when your child doesn’t do what you’re demanding, the problem isn’t with the child but with what it is you’re demanding. It’s remarkable how few books written for parents even raise this possibility. The vast majority of them take whatever their readers want their kids to do as the point of departure, and then offer techniques for getting compliance. In most cases, these techniques involve “positive reinforcement” or “consequences” – that is bribes or threats. In some cases, they involve more thoughtful and respectful ways of interacting with children. But almost never are parents encouraged to reconsider their requests.”

I find this so refreshing. And I would say it happens even less frequently in the equine world, hence my need to quote from parenting books.

We all need to be consistent when teaching boundaries, and it is great that this is so well-recognised. But sometimes I think we have gone too far the other way. From the point of view of the horse/child, our boundaries must often seem totally arbitrary and not sensible. If we could be slightly more flexible in our choice and implementation of boundaries then we could allow a lot more harmony into our relationships. Instead of trying to enforce an unreasonable boundary we can simply relax it slightly. The occasional relaxing of boundaries
does not turn anyone into monsters, very often the opposite can happen and our horses can become safer because there is less confrontation. The biggest obstacles to our relaxing of boundaries are our egos and our fear of what the consequences might be. Those are not reasons to continue to enforce unreasonable boundaries, just reasons to explore within ourselves and our motivations for choosing our boundaries.

The accompanying photograph shows a time when my ego got the better of me. It was a sponsored ride and I wanted to do the photographer’s fence and buy the picture. My horse refused the jump a number of times and ultimately I fell off. I decided not to try again. ‘What? And teach your horse that refusing gets him what he wants?’ I hear you say. Actually, since then I have started listening and generally allow him to refuse if he doesn’t want to jump. He very rarely refuses, despite there never being any consequence for “non-compliance”. If he does then there is a reason for it – on the day of the sponsored ride I am pretty sure that the reason was the hard ground at that particular fence hurting his shoulders (long-standing problem). My safety was compromised, not by my horse’s “disobedience”, but my failure to listen to him.

The opportunity to make choices and decisions is very often lacking from both traditional and “natural” horsemanship. Almost all forms of instruction, including most clicker training and positive reinforcement, involve manipulating our horses’ behaviour to suit our own goals. But what about our horses – do they not have opinions too?

It is well-documented that we benefit from making choices, for example Alfie Kohn goes on to say (with references):

“When teachers give their students more choice about what they’re doing, the results are impressive. According to one summary of the research, the advantages include ‘greater perceived competence, higher intrinsic motivation, more positive emotionality, enhanced creativity, a preference for optimal challenge over easy success, greater persistence in school (i.e. lower drop-out rates), greater conceptual understanding, and better academic performance’.”

There’s no scientific evidence to suggest that horses might experience all of this, and I’m not suggesting that it all applies to horses. But our mammalian brains are not so different that I think the analogy is irrelevant. Why would horses not also benefit from a share in the leadership, after all, that is what happens in a wild herd. Different horses take on the leadership role in different situations, depending on their expertise and desires. My experience with my horse certainly convinces me that there is a psychological benefit to us sharing the decision-making and that this enhances our mutual trust and relationship.

Relaxing boundaries is not something that should be done instantly as this can indeed create monsters that are unhappy in their confusing new world of freedom. This is a mistake often made by people who suddenly decide that they want to switch to using pure positive reinforcement and drop all their boundaries. The changes should be made gradually, giving you both opportunities to feel your way and work out what is genuinely important to you. The journey becomes more about moving the boundaries than enforcing them and our goals can become more about the relationship and mutual understanding than the jump or competition. Whether other people like or approve of our new goals can matter less and less as we enjoy the benefits of our new way of “working” with horses.

You may laugh at my naivety but I am looking forward to having a two  year-old. I am looking forward to learning more about myself, my son and our journey together. I refuse to call it terrible…..

Feb 212010
 

Often “modern” trainers talk about traditional training with a sense of moral high ground and perhaps a note of superiority creeping into the voice during any comparison of tradition and modern horse training. I think the term traditional is often incorrectly used as a substitute label for a belief that a method of training is wrong, old fashioned and out dated. So, what is traditional and what is modern? It seems to me that if we are to make any reasonable comparison we should first establish what might be encompassed in these ideologies.

Perhaps we should turn to the dictionary for a more accurate definition?

TRADITIONAL; handing down from generation to generation of opinions and practises; the belief or practise thus passed on.

If we take this meaning of traditional, it encompasses many successful styles of riding and training such as the European Riding Schools, The British Horse Society, Germanic Dressage trainers as well as the Vaqueros to name but a few. Through these methods of training the potential of the horse as an athletic performer has been stretched considerably. These traditional methods have in many cases stood the test of time and have been extremely successful at getting horses to do what trainers wanted them to do. These traditional methods worked and continue to work or they would have been abandoned long ago.

So if the negative classification “traditional” is not due the length of time a method has survived or the success it has enjoyed, it must relate to the content of the training method. Exploring the content of traditional methods we find a common thread through them all. No matter how well concealed or attractively labelled there is a definite content of punishment and force that seem to run through these methods. The use of punishment or avoidance of negative stimulus to motivate horses learning, is perhaps one mark of traditional training. The whip and the spur are the most obvious aids of the traditional methods.

Having identified what we mean through the term traditional it is equally important to consider, what is modern? In the dictionary modern simply refers to; of present or recent times. Again here lies a problem, traditional trainers are improving their skill and updating techniques and are still currently used in the vast majority of training yards around the world, so they must be modern. However, just because a method is currently being used doesn’t make it modern.

When we talk of modern training we are really talking of the methods of motivating the horses’ performance. Many people now consider a method of training to be modern provided it appears to use a minimum amount of force and therefore many Natural Horsemanship methods fall in to this category.

However, I am not sure that we have finished the evolution of horse training just yet. While Natural Horsemanship may be relatively recent is it really modern? If we look at the training of a few other species we find the answer to this question.

In modern marine mammal training the use of the scientific principle of behaviour are the natural choice of trainers. Dog training is evolving into the more common place use of operant conditioning in the form of clicker training. Zoos are happy to use positive reinforcement to train large often potentially dangerous animals to comply with the challenging difficulties of confinement and zoo management.

For me, modern horsemanship is not Natural Horsemanship, which is just a step on the evolution of equine training, but rather modern is the applied science of behaviour. Behaviour is a method of training where the rules are studied, proven and where the principles can be applied in different species. The principles of behaviour underpin all other training methods and this is why I believe that behaviour training is the most modern and up to date ways of training equine currently available.

Having identified likely traits and examples of both modern and traditional methods of training we can make a comparison between traditional force based methods of training and the application of the science of behaviour.

Difference No 1 – The way the horse is motivated.

In traditional training, punishment or the avoidance of negative stimuli are the main motivating elements of training. The horse works to avoid the whip or release the pressure of the spur and bit. In modern training, the use of positive reinforcement for desirable behaviours is a common motivation for the horse. When negative reinforcement is used in modern training it is used minimally and is not escalated to excessive physical force. In modern training the use of punishment is highly undesirable.

Difference No 2 – How mistakes are viewed.

Mistakes made during traditional training are seen as a hindrance and are the cause of frustration which slows learning down. Mistakes are seen as something to be avoided as much as possible. Modern training on the other hand, expects the horse to make mistakes. Mistakes are seen as essential to learning, hence the term trial and error learning. The modern trainer recognises that during the process of learning, mistakes provide the horse with important feed back on consequences of their behaviour.

Difference No 3 – The use of successive approximation.

Modern trainers understand the process of shaping behaviour and create written shaping plans for their training goals. Small logical steps in the learning process are considered essential. Desired behaviours are broken into as many small steps as possible and each step is completed before training progresses. In traditional training there is an awareness that horses have to learn things in the correct order, but the steps are generally large and no written plan exists.

Difference No 4 – The thinking required of the animal.

In traditional training the horse is required to comply and perform with what is expected of it when asked, without question. The traditionally trained horse has to get on with doing what it is told to or face the consequences. The horse is not allowed to have an opinion and if it does, it is often considered to be stubborn or difficult. Questioning the process of learning and experimentation are not acceptable in traditional methods of training. Modern trainers want the horse to think and experiment with the learning process. In fact, modern trainers use operant conditioning which requires the horse to solve problems and think for itself.

Difference No 5 – The application of direction

In modern training the use of operant conditioning means that the horse is encouraged to offer behaviours. The horse is likely to offer behaviours because it is motivated to seek the positive consequences of their actions and the trainer selects the appropriate behaviour to reinforce. In essence the horse performs and the trainer responds. In more traditional training the trainer applies pressure through the aids and the horse tries to find the behaviour that will avoid the discomfort. The trainer gives instructions and direction to the horse through force and physical discomfort that are likely to result in a desired behaviour. In other words the trainer acts and the horse reacts.

Difference No 6 – Understanding the science.

Traditional trainers know what to do to get the horse to comply, but not always why it works. Traditional trainers tend to have very little understanding of the consequences of the application of punishment on learning but they know it might get the desired results. Traditional methods of training use the principles of the science of behaviour even though they do not realise it or do not really understand the correct application. Modern trainers fully understand the consequences and effects of punishment, negative reinforcement and positive reinforcement on equine behaviour. The modern trainer understands a full range of scientific principles, such as counter conditioning, systematic desensitisation and flooding and knows how to use it appropriately.

Difference No 7 – Asking why behaviour exists

Modern trainers spend a great deal of time asking, “Why does my horse behave the way it does?” Accepting that horses have a reason for everything they do is the mark of a modern trainer. Understanding the causes of behaviour allows the modern trainer to apply the correct training to each and every training situation. The modern trainer thinks with the horses’ brain and in doing so empathises with the horse. Traditional training tends to expect the horse to get on with it. Consideration of the horses’ emotions is not a notable part of traditional training. Traditional training focuses more on how to over come difficulties without much consideration for the reason they may exist.

Difference No 8 – Methods of getting results

Traditional training tends to have a set pattern of training that is applied to all horses and all problems. No consideration is given to the horses’ individual distinctiveness or learning style, every animal is expected to fit the method. Modern trainers tend to have ten solutions to one problem and not one solution to ten problems. Modern trainers find the best approach to each individual horse and adapt their training to suit each horse as an individual. If one way of teaching a desired behaviour is not working, a modern trainer will try something else and keep trying new things until they succeed without ever resulting to physical force.

Difference No 9 – Blame and labelling

In traditional training methods problems and errors in the training process tend to be blamed on the horse. Horses are labelled as stubborn, difficult or naughty and the trainer then acts towards the horse according to the given label. In more modern training the trainer takes full responsibility for any problems or difficulties that arise during training. Blame is negative and unproductive, responsibility is constructive. By taking responsibility for a problem the modern trainer remains in control of the situation and can change the outcome by changing their behaviour. When the horse is blamed for the problem then the trainer can do little but wait for the horse to do something different.

Difference No 10 – Control

The traditional trainer wants control and dominance over the horse and is happy to show the horse “who is boss” and “teach them a lesson.” The modern trainer wants a partnership and a balanced relationship with equal input from each side.

Difference No 11 – How the trainer views the horse

Modern trainers understand the complexities of working with a flight animal that still requires every generation to be domesticated. Modern trainers understand the true nature of equine to be fearful inquisitiveness. Modern trainers believe in the true nature of equines, namely that they are adaptable willing creatures who will comply with the requirements of a much weaker and slower species. Horses are stronger and faster than we are and in truth do not have to do anything we want, yet in most cases they do. It is widely believed in traditional training that horses can be deliberately lazy and do things to deliberately upset the trainer. The traditional trainer is more inclined to call the horse stupid or label them as awkward and deliberately difficult. The traditional trainer is more likely to become frustrated at the horses poor performance than the modern trainer.

Perhaps by now you are thinking am I a modern trainer? Well the answer lies in how you think and behave as much as in how your horse behaves. Do you understand the science of behaviour and the applications of principles such as positive and negative reinforcement, extinction bursts and spontaneous recovery? Do you create a detailed shaping plan before you commence training and for each lesson do you shape the desired behaviour correctly? Do you put the horse first and create a win win situation every time? Do you use systematic desensitization and counter conditioning to over come the fears and phobias your horse may have? Do you have a partnership with your horse and are you happy to accept the responsibility for problems? Does your horse show enthusiasm for training sessions and even after mistakes continue to show enthusiasm for learning? Do you look for behaviours to reward rather than behaviours to shut down or punish? If you answered yes to all the above then the chances are you are a modern trainer and you should reward yourself for your enlightened behaviour and thinking.

Unfortunately despite my best efforts to classify training methods there really are no hard and fast rules for the label of traditional or modern. Age of the method certainly does not determine whether it is traditional. Twenty four centuries ago, I am pretty sure Xenophon would have been considered modern. In fact he describes the effects of both positive and negative reinforcement 2,400 years before they are “discovered.” Much of his writing speaks with compassion and empathy for the horses’ plight and it still has relevance today.

In 1959 Üdo Burger in his book, The way to Perfect Horsemanship, writes “All horses must eventually learn to stretch the reins and none are incapable of doing so. To form the horse into the shape that will give the rider complete control, a certain tension of the reins is essential. However, it should not be forgotten that horses are not all made the same: we will never be able to effect radical change in the shape of a body and we cannot expect to mould two horses into an identical form.”

Many “traditional” trainers have a great understanding and empathy with the horse, they have soft hands and can help the horse to learn what is required of it with the minimum of pressure or force. Many trainers who would be considered “modern” have poor timing, use excessive amounts of punishment and negative reinforcement and force the horse to comply all of which is carefully concealed with clever marketing and scientifically incorrect analysis.

Given the same length of time and quality of animal the results achieved by a modern or traditional trainer could produce a performance of identical standards. It is obvious that the difference between traditional and modern training lies not in the results but more in how the behaviour was achieved. The thought processes and behaviour of the trainer is the difference between traditional and modern methods.

Crediting the horse with emotions and empathising with their difficulties in adapting to domestication are the great leaps forward in human thinking that have allowed us to improve equine training, which we can compare to traditional methods. Understanding the practical application of the science of behaviour is the development that will create the modern trainer of the future.

As always we “modern” trainers should guard against complacency working to improve and understand more in the hope that we are just part of the evolution in horsemanship and that in time, better and even more “modern” methods of training will advance our partnership with the horse.

So perhaps for the time being we should not compare modern and traditional, as the saying goes “don’t compete create.”

By Ben Hart

www.hartshorsemanship.com

© Ben Hart September 2006

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Feb 142010
 

For a while a conundrum has been playing with my thoughts. It all started one chilly but sunny Saturday, during an ordinary training session, whilst training a horse that for the purposes of this article we will call ‘The Pony’. It was nearing the end of the session when The Pony tripped over a protruding root an came very close to stand on my foot. In an effort to preserve my foot I quickly asked the horse to move back with a little pressure on the chest. A fairly benign act in response to which The Pony quickly ceased stumbling toward my vulnerable metatarsals and politely backed away. The training session continued without incident but a question remained in my mind.

Pressure and release is a commonly used method of horse training, within equestrian literature it is often cited as a simple but effective use of negative reinforcement. Whether it is a pressure on the chest of a horse to ask for a reverse, the use of the head collar to lead the horse, a gentle pressure on the reins to ask for a halt or the use of advance and retreat to approach a nervous horse, it is almost impossible to avoid the use of negative reinforcement in training. However until the incident with The Pony it had never occurred to me that positive punishment maybe an inextricable part of negative reinforcement. Can negative-reinforcement occur with out positive punishment? The Pony had be negatively reinforced for reversing away from me by the release of pressure, but it had been the addition of the pressure which had prevented further advancement.

Negative reinforcement is defined within all behaviour literature as the removal of an unpleasant or aversive stimulus in response to a wanted behaviour to reinforce the behaviour, and thus encourage the behaviour to reoccur in the future. This is a definition that most people are familiar with. However, the training incident with The Pony made me think – in order for something to be removed it must have been applied at some point in the past. For the aversive stimuli to be removed to reinforce a behaviour it must at some point have been applied. The addition of an aversive stimulus is the definition of positive punishment, the effect of positive punishment is that it reduces the likelihood of the behaviour it is a consequence of occurring in the future. Pressure on the chest of The Pony prevented further forward advancement towards my foot, so is it that I positively punished the forward movement? And as an extension of this thought, is it that every use of negative reinforcement begins with the use of positive punishment?

This is may seem like a conundrum based in the semantics of academic definitions but the practical consequences of positive punishment being inextricable from negative reinforcement are not dismissible. The most important practical consequence of positive punishment is that it discourages the behaviour it is associated with from occurring again. When applying the negative reinforcer, be it pressure or the advance of advance-retreat training, we must be careful that the behaviour it is being applied to is unwanted or the positive punishment would diminish a desired behaviour. The training should thus ensure that the negative reinforcer is attended to with regards to not only the timing of its release but also it’s application, this will ensure that wanted behaviours are not punished.

The problem of positive punishment being inextricable from negative reinforcement and the two training methods not being mutually exclusive is one that has impacts on training which could effect the psychology of the horse, the effectiveness of the training and the welfare of the horse. Punishment has been correlated with side effects which are important to our training of horses and must be understood to preserve the horse’s well being within training. Although this article is not the place to detail the problems and side effects of punishment I will briefly outline the most important ones below.

  • Punishment teaches only what not to do and does not suggest a more appropriate behavioural replacement for the one being punished.
  • Punishment can invoke emotional reactions in horses, such as fear or aggression. These reactions are more likely with physical punishment. In order to avoid these reactions, any punishment applied should be sympathetic to the horse’s personality i.e. how reactive they are and also to the situation. Positive punishment and negative reinforcement are both based in use of stimuli which are to a greater or lesser extent unpleasant for the horse, such as pressure, and as such it must be ensured that the horse is not stressed by the punisher in order to ensure emotional reactions are not experienced.
  • Pain-elicited aggression can be induced if painful physical punishers are used. Pain can heighten a flight/fight response and cause aggressive reactions in the horse as they try and escape the threat of pain, therefore positive punishers which cause pain should never be used in training.
  • Anxiety caused by punishment can actually impair the horse’s ability to concentrate and learn effectively. Extremes of emotion inhibit the brains cognitive abilities and thus impair attention.
  • Learned helplessness is a condition induced through the incorrect use of punishment. Learned helplessness occurs when the horse feels they cannot avoid punishment over a sustained period of time. The horse learns that any attempts to escape are futile and thus the horse will not attempt to escape or avoid the punishment, even once an escape or avoidance method is offered.
  • Avoidance behaviours – if the horse learns to associate a person or situation with punishment, the horse may logically try to avoid that situation or handler.
  • It is also possible for horses to selectively suppress the punished behaviour until punishment is less likely, either when the punishing handler is no longer present, or when the horse believes that it is less likely to be punished for the behaviour.
  • Punishment can reduce the horse’s interest in their work, if a horse is punished the horse’s motivation will be diminished and thus the horse is less likely to participate willingly in training.

If negative reinforcement by its definition begins with a positive punishment these problems that are associated with punishment are consequently also a problems intrinsic to the use of negative reinforcement. It is therefore essential that they are considered carefully if negative reinforcement is to be used in training. The application of the negative reinforcer must follow the rules of applying positive punishment if side effects are to be avoided in the horse.

The rule of applying punishment to avoid side effects are as follows, the punishment must be –

  • Immediate
  • Consistent
  • Never painful
  • Never dealt in anger
  • Specific to targeted unwanted behaviours and not delivered randomly or accidentally.
  • Never used during confusion

Obviously each horse has their own tolerance levels for different stimuli. An aversive stimulus for one horse may not be unpleasant for another. However given that negative reinforcement is based upon the release of an aversive stimulus, it is highly likely that the stimulus use as a negative reinforcer could also be a positive punisher for the horse. I would be interested to hear if anyone could think of a training scenario in which the negative reinforcer when applied could not be considered a positive punisher because I must admit I could not think of one.

To finish this article I would like to say that I don’t believe that we can avoid the use of negative reinforcement in training but any part of training that uses aversive stimuli, i.e. negative reinforcement or positive punishment should be carefully considered with regards to the strength of the stimulus and its application.

By Emma Lethbridge

www.emmalethbridge.com

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Feb 072010
 

Have you ever wondered how squirrels remember where they hid their food? Or how animals that migrate know the route to take each year? Or how birds living in large groups remember where their specific nest is among thousands? These are just some of the questions that spurred research into how the brain records information about the environment and the animal’s position in that environment. This work can help us to understand how feral horses find their way around their range and even how our domestic horses can find their way home if they escape or they end up without a rider.

Map and compass

Animal navigation is a complex process that we are only beginning to understand: first the animal determines its current location in relation to what he/she knows about and then chooses the appropriate direction of travel towards its destination. This is called the ‘map’ and ‘compass’ system (reviewed by Frost and Mouritsen, 2006). [N.B. for brevity I will use ‘she’ when referring to a horse]

Horses that live in large areas naturally ‘home range’- they move to different parts of their range as the seasons affect the available resources. Homing can be defined as navigation within near- to medium- distance unfamiliar space (reviewed in Frost and Mouritsen, 2006). Herds use the same routes every year and the alpha mare, who will have made the journey many times before, leads the movement of the herd within its home-range. So, how does the alpha mare know where to go?

Making maps

Since the 1970s, researchers have been studying the cellular mechanisms by which the processes of cognitive mapping, spatial learning and spatial memory occur. This just means studying at the level of cells how animals map their environment, learn about it and remember it.

Let’s consider the first time a horse moves to a new part of the herd’s home-range. When an animal is placed in a new environment, the brain processes sensory information about its surroundings – for horses, a great proportion of this information will be visual. Within minutes of experiencing the new ‘place’, about half of the million specialized brain cells called ‘place cells’ (first described by O’Keefe et al., 1971) in the part of the brain called the hippocampus are fired. The ‘view’ is split up into overlapping fields (‘place fields’) and each field is assigned a place cell. As the horse’s head moves into a place field, the cell assigned to that field fires and some cells stop firing, providing orientation in the field (reviewed in Rotenburg et al., 1996).

The place cells recording these overlapping fields are not actually next to each other – which is efficient because each place cell can be used in more than one spatial map. The hippocampus records the memory for several weeks and only if the information is to be retained does it move to the part of the brain where information is stored, the cerebral cortex (reviewed in Rotenburg et al., 1996). This mechanism has been proved for ‘near space’ navigation but is also relevant to longer distances because during a journey there will still be shorter-term destinations (e.g. resources along the way such as rivers to drink from).

Learning the route

Until 1996 scientists were not sure whether animals learn about their surroundings as a map or react automatically to various stimuli they come across. Two research groups helped to solve the mystery and significantly added to our understanding of cognitive mapping (Tsien et al. and Rotenburg et al. 1996). Both groups, using different methods, disrupted the way that connections between cells change in strength (called synaptic plasticity, which occurs during learning) and found that indeed, the animals were no longer able to navigate around their environments – spatial learning was affected. The involvement of synaptic plasticity shows the link between learning and spatial orientation so we now can hypothesize that animals, including horses, learn about their surroundings as a map rather than just reacting automatically to things in their environment.

Since this early work into place cells, two other types of brain cell have been discovered – head direction cells (HDCs) and grid cells. HDCs are those that fire when an animal orientates its head in a certain direction (Knierim et al., 1995). There are different HDCs for different head orientations and they are influenced by landmarks, and information concerning how the head moves.

Later, grid cells were discovered (Hafting et al. 2005). These are found in the part of the brain called the entorhinal cortex and fire strongly when an animal is in specific locations in an environment. Grid cells have multiple firing fields, which tesselate the environment in a hexagonal pattern. The grid cells are anchored to external landmarks, suggesting that grid cells may be part of a self-motion-based map of the environment. It has been suggested that grid cells add a ‘place code’ in the entorhinal cortex, providing associations between place and events (for example to associate a place with good resources) – needed for the formation of memories (Sargolini, 2006).

Finding the way

Exactly how animals navigate long distances is still being researched but there are some interesting concepts that are probably relevant to equine homing behaviour:

  1. Minimization of stimuli: We only pay attention to meaningful cues. In the same way that when asking for directions we don’t need to know the detail of who lives in all the houses you pass but just need to know where to turn right – or if you are looking for someone in a crowd who is meeting you at the airport you won’t notice the detail about the other people there – horses do not take note of all the cues in the environment, just the important ones (perhaps a big tree that is good for rubbing on or a sheltered site).
  2. Features theory: In the same way as above, we, and horses, can remember part of a route without having to remember everything about it.
  3. Context: In the same way that we might not recognize the postman out of his uniform if we see him in the supermarket there is a context-specific element to mapping.
  4. Landmarks: It is likely that horses use landmarks in recognizing their home range. The famous ethologist Tinbergen proved that animals use landmarks to find their nests. For example, if an insect’s nest is surrounded by a set formation of pine cones, the insect leaves home, you move the pine cones to a new location, the insect will return to the pine cones and not to the nest. Landmarks that horses might use could be trees, boulders, houses etc or could be patterns of smells.
  5. Prototype theory (Hernstein, 1976): if a route is followed many times then the ‘ideal’ will be remembered. For example, if you do the same journey to work every day you don’t remember the first time in particular, you only remember specific times if they were very good or bad. In the same way, if a foal takes a similar route many times she will only remember some of them.
  6. Central pattern generators (Randall et al. 1997): are sets of brain cells that activate cells resulting in movement according to pre-set patterns. When a horse sees a visual stimulus associated with its home range, central pattern generators could cause automatic walking behaviour towards that visual stimulus. Animals do form a ‘map’ as described above but there might be an element of automatic behaviour within that map.
  7. Time: Horses need to know when to move from one area at a particular time to get to the new area at the right time for plentiful resources. It is suggested that a ‘time tag’ could be added to the memory formation (e.g. when the trees are green, the journey should be started).

Summary

When a horse is moving within her home range or being ridden out on a hack, she is learning about the environment – including about information about landmarks and features – such as areas that are sheltered or particularly good grazing areas. If the horse is wild, feral or kept almost naturally in a herd, as a foal she will follow the group to different resources at different times of the year. She will remember (via prototype theory above) the ideal situation with respect to, for example, crossing a river.

Physiologically, as the foal enters new environment, place cells will be fired within the place field, and when she orientates her head in a certain position, the corresponding head direction cells will fire, influenced by landmarks and information about the position of her head during orientation. When she is in some specific locations within her home range, grid cells will fire, to add the place coding to the memory associated with the event (good areas for food, for example).

Although further research is needed into how place cells, head direction cells and grid cells work together in determining orientation in space and in navigation, we are on the way to an improved understanding of the complex mechanism of homing behaviour.

By Suzanne Rogers

www.learningaboutanimals.co.uk

© Learning About Animals 2009

(Enjoyed this article? Then please donate a little to The Equine Independent to keep us writing. You can donate via paypal to mail@theequineindependent.com – Many thanksm Emma Lethbridge -editior)

References:

Frost, B.J. and Mouritsen, H. (2006) The neural mechanisms of long distance animal navigation. Current Opinion in Neurobiology 16, 481-488

Hafting et al. (2005) Microstructure of a spatial map in the entorhinal cortex. Nature 436, 801-806

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