“Dimensions of Animal Consciousness”

If humans try to make sense of variations of consciousness across the animal kingdom using a single sliding scale to rank species as “more conscious” or “less conscious” than others, claims Birch et al., they will inevitably neglect important dimensions of variation. There is a need for a multidimensional framework that allows the conscious states of animals to vary continuously along many different dimensions, so that a species has its own distinctive consciousness profile. This article presents such a multidimensional framework for understanding interspecies variation in states of consciousness. The framework distinguishes five key dimensions of variation: perceptual richness, evaluative richness, integration at a time, integration across time, and self-consciousness. For each dimension, existing experiments that bear on it are reviewed and future experiments are suggested.