Consciousness, Comparative Perspectives

Do animals have mental experiences or are they closer to robotic zombies? Most animal behaviorists these days, at least those steeped in understanding evolutionary continuities in brain and mind organization, are happy with the provisional conclusion that many other animals, surely mammals and birds, perhaps even some invertebrates (octopuses), are conscious beings. However, few would be able to outline how one could credibly (scientifically) study such aspects of animal minds. The perennial problem, as noted by ethologist Niko Tinbergen (1951) in his seminal treatise, The Study of Instinct, was simply “Because subjective phenomena cannot be observed objectively in animals, it is idle to claim or deny their existence” (p. 4). With the advent of modern neuroscience, that statement no longer has the ring of truth that it used to, even though a series [Page 190]of famous animal behaviorists still tend to subscribe to Tinbergen's dictum.

Of course, the study of experience in animals had to wait for the maturation of neuroscience in the psychological and animal behavioral sciences, which started in earnest in the early 1970s. Before then, compelling experimental strategies could not be generated to study the nature of animal experiences at a scientific-causal level, even though there had been abundant treatises considering such issues at conceptual-inferential levels (not considered here). We can now be confident that all mammals and birds are beings that have internal experiences, especially relevant for engendering the qualities of “rewards” and “punishments” they encounter in the world (i.e., affective consciousness, which can be monitored by the rewarding and punishing states evoked by artificial activation of brain emotions stimulation with direct electrical or chemical stimulation of the brain). The existence of their perceptual experiences (i.e., cognitive consciousness) is likely but harder to understand neuroscientifically, since there are no comparable evaluative measures and one has to infer experience simply from an animal's capacity to discriminate stimuli. This tells us little about the experience itself. Thus, this entry will focus on affective consciousness—the experienced feeling of emotions—rather than perceptual or cognitive consciousness—the felt experience of the world, since the neuroscientific evidence is much stronger for the former than the latter. However, Don Griffin and Bjorn Merker have made a strong and reasonable case for the conclusion that animals do have subjective cognitive experiences of the world.

Why is a resolution of the opening question so important? Perhaps most poignantly, it could modify how we envision animals as fellow creatures, leading hopefully to more sensitive practices in animal research, animal husbandry, and our reverence for life. Beside such practical and philosophical issues, a scientific understanding of “lower order” (more primal) core forms of consciousness in animals is culturally important and helps set the stage for deeper understanding of human consciousness than is currently possible through research on people, where the detailed neuroscientific work simply cannot be done. Thus, a scientifically satisfactory understanding of higher order consciousness (“awareness”) may not be achieved without illuminating the foundations of subjective experience in the animal kingdom.