Cognitive Neuroscience and Animal Consciousness

The problemof animal consciousness has profound implications on our conceptof nature andofour place in the natural world. In philosophyof mind and cognitive neuroscience the problem of animal consciousness raises two main questions (Velmans, 2007): the distribution question (are there conscious animals beside humans?) and thephenomenologicalquestion (what is it like tobe a non-human animal?). In order to answer these questions, many approaches take into accountsimilarities and dissimilarities in animal and human behaviour, e.g. the useof language or tools and self-recognition in a mirror (Allen and Bekoff, 2007);however, behavioural arguments do not seem to be conclusive(Baars, 2005). Cognitive neuroscience is providing comparative data onstructural andfunctional similarities, respectively called homologies andanalogies.Many experimental results suggest that the thalamocortical system is essential for consciousness (Edelman and Tononi, 2000; Tononi, 2008). The argument from homology states that the general structureof the thalamocortical system remained the same in the last 100-200 millionyears, because it is neuroanatomically similar in all the present and pastmammals, and it did not change muchduring phylogeny(Allen and Bekoff, 2007). The argument from analogy states that the key functional processes correlated with consciousness in humans are also present in all other mammals and many other animals (Baars, 2005).These processesare information integration through effective cortical connectivity(Massimini et al., 2005; Rosanova et al., 2012), and elaboration of information at a global level (Dehaene and Changeux, 2011). On this basis, the CambridgeDeclaration on Consciousness statedthat all mammals, birds, and many other animals (such asoctopuses) possess the neurological substrates of consciousness (Low et al., 2012). Conscious experience is private (Chalmers, 1995; Nagel, 1974), therefore the answer to the phenomenologicalquestion may be impossible. Nevertheless, cognitive neuroscience may provide ananswer to the distribution question, showing that conscious experience is not limited to humans since it is a major biological adaptationgoingback millions of years.