Animal Emotions and Mental Health: Evolutionary Foundations and Measurement Methods

Abstract

Understanding animal emotions has become one of the key and hot topics in the past few decades of cognitive science and behavioral ecology research. More and more evidence show that many animals have emotional capacity that affect their survival and reproduction. This paper reviewed the evolutionary basis, brain mechanism and measurement method of animal emotions and affective states. First, we analyzed how the experience of emotions serves as an individual’s adaptive behavior function and social regulation mechanism for the individual to understand the outside world and self-awareness. Based on comparative neuroanatomy and evolution studies, it was found that important emotional circuits such as amygdala and prefrontal cortex evolved in vertebrates, as well as similar affect mechanisms in birds. This review summarizes the most used methods, which include many different forms from psychological or behavior perspective such as the emotional cognition based on psychological bias or emotion cognitive and decision-making (emotional decision making and cognitive test based), including cognitive bias method and preference choice methods and others. In addition, the specific cognitive paradigm method such as the cognitive bias method is discussed for measuring animals’ subjective feelings and affective states more effectively. We hope this review would help foster human perception of animals’ subjective emotional experiences, establish theoretical basis and improve the research approach about animal feeling, animal welfare and mentality as well as facilitate our knowledge to find clues on the evolutionary origin of human and other animal emotions.