Research into rat cognition including metacognition, empathy, and emotional contagion has profound implications for understanding their welfare needs and our moral obligations to them.
Rat cognition welfare science is transforming our understanding of what rats experience in laboratory settings. The demonstration of metacognition - knowing what you know - suggests cognitive complexity comparable to monkeys. Empathy-based helping behaviour indicates emotional complexity that should inform how we think about rat social needs. Emotional contagion means rats in adjacent cages may experience distress from witnessing other rats' pain or stress responses, raising questions about how laboratory environments are designed. Cognitive bias assessment gives researchers a tool to measure positive versus negative affective states. Together, these findings support treating laboratory rat welfare with the seriousness previously reserved for larger animals.