Development of a standard test to assess negative reinforcement learning in horses
Introduction
The value of domestic horses is dependent on their ability to learn the various tasks set by humans. The horse sector would therefore benefit from the development of standardised methods to measure learning in horses. Equine learning ability has been investigated mainly in tests based on positive reinforcement (Nicol, 2002), including visual discrimination tasks (Gabor and Gerken, 2010), target touching and following (Christensen et al., 2012, Valenchon et al., 2013) and detour learning (Baragli et al., 2011). In contrast, most horse training is based on negative reinforcement (McGreevy and McLean, 2010). Studies have shown that horses’ general learning ability cannot be evaluated based on performance in one test alone (Visser et al., 2003, Wolff and Hausberger, 1996). Rather, learning ability appears to be specific to the learning mechanism targeted, thus, performance in a test based on positive reinforcement does not necessarily predict performance in a negatively reinforced test. Consequently, investigations of horses’ ability to learn through negative reinforcement and factors influencing this ability require a test based on negative reinforcement.
Negative reinforcement is an instrumental learning mechanism, where the instrumental response turns off an aversive stimulus (Domjan, 2010). By turning off the aversive stimulus the animal is rewarded for the instrumental response and will be more likely to perform the same response when it encounters the same aversive stimulus in the future.
In horse training the aversive stimulus is often some kind of pressure to the body of the horse, such as leg pressure or rein tension. The force of the pressure is increased until the correct response is obtained and rewarded by release of the pressure (McGreevy and McLean, 2010). Currently, no standardised test for evaluating equine learning ability through negative reinforcement is available, and the present study aimed to develop an objective test in this area. Learning was evaluated in a pressure-release task, where the pressure was applied in a standardised manner by an algometer, which also measured the force of the required pressure.
We hypothesised that the force required for the horse to respond correctly would decrease with repetition within as well as between days.
Section snippets
Materials and methods
The experiment was conducted during November 2012 and conformed to the Guidelines for ethical treatment of animals in applied animal behaviour and welfare research [http://www.applied-ethology.org/ethical_guidelines.html].
Results
The applied force ranged from 0.04 N to the actuator limit of 30 N (median [25; 75% quartile]: 17.83 N [8.22; 30]). There was one instance of what could have been interpreted as a threat to kick, but generally the horses tried to avoid the pressure by moving sideways or forward or backwards, the two latter being prohibited by the handler. Some horses moved only one leg in response to the pressure, whereas others took several steps sideways; both types of response were rewarded. The horses had
Discussion
The results confirmed our main hypothesis. There was a significant decrease in force through the trials within the first day and the regression intercept was significantly higher on the first day compared to the second and third day. This indicates that the horses learned the task through negative reinforcement. Learning occurred primarily on the first day whereas the lower intercept on day 2 compared to day 1 indicates that the horses remembered the task. Hence, we present a novel,
Acknowledgements
We would like to thank the horse owners for kindly allowing us to use their horses; Anna Feldberg Marsbøll and Maria Vilain Rørvang for help with the experiments. This study was funded by The Independent Danish Research Council|Technology and Production (grant no. 11-107010) and The Graduate School of Science and Technology, Aarhus University.
References (24)
- et al.
Does learning performance in horses relate to fearfulness, baseline stress hormone, and social rank?
Appl. Anim. Behav. Sci.
(2012) - et al.
Horses use procedural learning rather than conceptual learning to solve matching to sample
Appl. Anim. Behav. Sci.
(2010) - et al.
Interactions between brain structure and behavior: the corpus callosum and bimanual coordination
Neurosci. Biobehav. R
(2014) Interocular transfer of learning in horses (Equus caballus)
J. Equine Vet. Sci.
(1999)- et al.
Relationship between number of conditioning trials per training session and avoidance learning in horses
Appl. Anim. Behav. Sci.
(1993) - et al.
Motor and sensory laterality in thoroughbred horses
Appl. Anim. Behav. Sci.
(2005) - et al.
Idiosyncratic motor laterality in the horse
Appl. Anim. Behav. Sci.
(2005) Equine learning: progress and suggestions for future research
Appl. Anim. Behav. Sci.
(2002)- et al.
Learning performances in young horses using two different learning tests
Appl. Anim. Behav. Sci.
(2003) - et al.
Learning and memorisation of two different tasks in horses: the effects of age, sex and sire
Appl. Anim. Behav. Sci.
(1996)
Detour behaviour in horses (Equus caballus)
J. Ethol.
Marginal semiparametric multivariate accelerated failure time model with generalized estimating equations
Lifetime Data Anal.
Cited by (14)
Understanding and treating equine behavioural problems
2023, Veterinary JournalA rein tension signal can be reduced by half in a single training session
2021, Applied Animal Behaviour ScienceCitation Excerpt :They trained horses to yield the hindquarters by applying pressure on the horses’ hindquarters using an algometer. Inspired by Ahrendt et al. (2015), this study was designed to learn more about negative reinforcement learning of rein tension signals in horses. Our hypothesis was that through the correct application of negative reinforcement, the magnitude of a rein tension signal can be substantially reduced over the course of a single training session.
Cutting to the chase: How round-pen, lunging, and high-speed liberty work may compromise horse welfare
2019, Journal of Veterinary BehaviorCitation Excerpt :Lunging and the round-pen can also be places where horses can learn important responses in a safely enclosed environment. Negative reinforcement is the most common form of reinforcement in horse training (Ahrendt et al., 2015; McLean & Winther Christensen, 2017; Murphy & Arkins, 2007) and, when applied correctly at the beginning of the horse's education, can effectively train the horse to trial solutions as soon as pressure is applied. In the round-pen, negative reinforcement can be used to train specific responses and low levels of pressure can easily be applied and removed while the horse continues to travel forward.
Behavioral Responses to Touch and Leading in Lippizan Mares: Natural vs. Traditional Handling Method
2024, Indian Journal of Animal ResearchExploratory behaviour towards novel objects is associated with enhanced learning in young horses
2021, Scientific Reports