Measuring emotional processes in animals: the utility of a cognitive approach.

Contemporary researchers regard emotional states as multifaceted, comprising physiological, behavioural, cognitive and subjective components. Subjective, conscious experience of emotion can be inferred from linguistic report in humans, but is inaccessible to direct measurement in non-human animals. However, measurement of other components of emotion is possible, and a variety of methods exist for monitoring emotional processes in animals by measuring behavioural and physiological changes. These are important tools, but they have limitations including difficulties of interpretation and the likelihood that many may be sensitive indicators of emotional arousal but not valence-pleasantness/unpleasantness. Cognitive components of emotion are a largely unexplored source of information about animal emotions, despite the fact that cognition-emotion links have been extensively researched in human cognitive science indicating that cognitive processes-appraisals of stimuli, events and situations-play an important role in the generation of emotional states, and that emotional states influence cognitive functioning by inducing attentional, memory and judgement biases. Building on this research, it is possible to design non-linguistic cognitive measures of animal emotion that may be especially informative in offering new methods for assessing emotional valence (positive as well as negative), discriminating same-valenced emotion of different types, identifying phenotypes with a cognitive predisposition to develop affective disorders, and perhaps shedding light on the issue of conscious emotional experiences in animals.