On 7/7/2012 a group of prominent neuroscientists signed a declaration supporting the view that non-human animals experience consciousness. The statement claims to be a ‘re-evaluation of previously held preconceptions’. It states that:
‘Convergent evidence indicates that non-human animals have the neuroanatomical, neurochemical and neurophysiologial substrates of conscious states, along with the capacity to exhibit intentional behaviours‘.
Unfortunately the declaration doesn’t define clearly what exactly the ‘consciousness’ they are referring to is. Instead the text switches between referring to different elements of conscious experience, such as arousal (e.g. levels of sleep and attentiveness), conscious decision making, perceptual distortions (e.g. hallucinations) and the experience of emotional states. As the concept of consciousness is a notoriously difficult one to define, the lack of an operational definition makes the declaration somewhat difficult to interpret.
A further peculiarity of the declaration is that it states something which I suspect the vast majority of scientists working in the fields of neuroscience, psychology and animal behaviour have believed for some time. Indeed I suspect a significant proportion of the ‘general public’ would accept that most animals have some level of conscious understanding, especially mammals. The declaration isn’t therefore heralding a breakthrough in scientific understanding, even if it does contradict certain religious and philosophical standpoints that propose consciousness as a uniquely human characteristic.
Despite these reservations, the declaration may prove to be of importance. It focuses on the commonalities between different animals in the neural structures supporting various conscious experiences, and discusses the implications this may have for understanding the development of consciousness through evolution. It represents an official acknowledgement that a larger range of animals experience consciousness that many may have previously believed, based off the proposition that absence of a cerebral cortex does not preclude conscious thought. Those animals considered ‘conscious’ can therefore include non-mammalian creatures such as insects and cephalopods. The declaration may hopefully lead to greater discussion of both the nature of consciousness, and the relationship between humans and other animals. More importantly it may facilitate political changes to ensure the more humane treatment of animals.
A full text of the declaration can be found at http://fcmconference.org/img/CambridgeDeclarationOnConsciousness.pdf