Sensitivity to reward change: a novel cognitive approach to understanding and measuring affective state in animals

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The question as to what feelings animals might or might not experience underlies not just the assessment of animal welfare, but public concern for how captive animals are treated. As the number of animals used in agriculture, research and kept as pets continues to increase, for example over 700million chickens are farmed and killed annually in the UK for meat production alone, the belief that many animal species have the capacity to suffer drives our desire to improve the housing conditions and husbandry procedures of those animals. Yet, because such experiences are private, they cannot be accessed directly. Instead, welfare scientists use indirect measures thought to reflect animals' emotional states. These indicators are often behavioural (e.g. approaching food) or physiological (e.g. a change in heart rate). However, despite the benefits of these measures, they have critical limitations. For example, an animal's heart rate will increase in the presence of something fearful (e.g. a predator), but will also increase during the experience of something pleasurable (e.g. food), such that reliable interpretation of this measure becomes impossible. For this reason, research into developing new approaches to measuring animal emotion and mood is urgently required to allow a more accurate and targeted assessment of animal welfare. Research that underpins and advances in animal welfare science in this way will have a major impact on a captive animal population that consists of large numbers of individuals. For example, there are an estimated 10 million owned dogs in the UK (2006).The aim of this proposed research programme is therefore to develop a completely new approach to understanding and measuring emotions and moods in animals that will significantly advance our assessment of animal welfare, and this approach is based on reward evaluation.How we feel about a reward that we have been given depends not just upon its absolute value, but its value compared to what was expected. So, although you might normally be happy to receive a pay rise, you will be disappointed if you were expecting to be offered a promotion as well. This sensitivity to the contrast between what you expected and what you actually received is common to many animal species and is thought to help individuals to make appropriate decisions. It has recently been demonstrated for the first time that the mood an individual is currently experiencing can influence its sensitivity to a change in reward, with those animals in a positive mood recovering sooner from an unexpected loss of reward. This therefore provides an exciting opportunity to use sensitivity to reward change as a novel measure of animal emotion and mood. Initial research indicates that sensitivity to reward change is a quick, effective and non-invasive way of measuring moods in animals. However, this approach needs to be studied in more detail in order to determine the full extent of its potential.In this project we will be studying emotions and moods in domestic dogs, both owned (pet) dogs and those housed at rescue centres. In contrast to laboratory and farm animals, the study of emotions, moods and associated behaviour in dogs, because they share a close relationship and environment with people, can reveal valuable insights into the interaction between cognition (e.g. decision-making) and emotion that applies not just to dogs and other animal species, but also to humans themselves. Whilst the outcomes of the study will clearly have a direct impact upon the welfare assessment of dogs, resulting in ways to improve the welfare of dogs housed in rescue centres and rehoming success, it will have a far wider impact, delivering techniques that can be applied across captive animal species.