Animal Consciousness

Abstract

After reviewing the literature on current knowledge about consciousness in humans, we present a state-of-the art discussion on consciousness and related key concepts in animals. Obviously much fewer publications are available on non-human species than on humans, most of them relating to laboratory or wild animal species, and only few to livestock species. Human consciousness is by definition subjective and private. Animal consciousness is usually assessed through behavioural performance. Behaviour involves a wide array of cognitive processes that have to be assessed separately using specific experimental protocols. Accordingly, several processes indicative of the presence of consciousness are discussed: perception and cognition, awareness of the bodily-self, selfrelated knowledge of the environment (including social environment). When available, specific examples are given in livestock species. Next, we review the existing evidence regarding neuronal correlates of consciousness, and emphasize the difficulty of linking aspects of consciousness to specific neural structures across the phyla because high-level cognitive abilities may have evolved independently along evolution. Several mammalian brain structures (cortex and midbrain) are involved in the manifestations of consciousness, while the equivalent functional structures for birds and fishes would likely be the pallium/tectum and midbrain. Caution is required before excluding consciousness in species not having the same brain structures as the mammalian ones as different neural architectures may mediate comparable processes. Finally, specific neurophysiological mechanisms appear to be strongly linked to the emergence of consciousness, namely neural synchrony and neural feedback. Considering the limited amount of data available and the few animal species studied so far, we conclude that different manifestations of consciousness can be observed in animals but that further refinement is still needed to characterize their level and content in each species. Further research is required to clarify these issues, especially in livestock species.

In Search of the Origins of Consciousness

“…This raises the intriguing possibility that second-order conditioning alone might already be a positive marker of consciousness, whether or not the stimuli are compound or novel. Second-order conditioning (but not on novel, compound stimuli) has been found in honey bees (Hussaini et al 2007) and even snails (Papini 2010, p. 366). Yet I also don't know of any experiments that have actively looked for second-order conditioning on subliminal stimuli in humans and failed to find it.…”

“…They are among the most intensively studied of all invertebrates, and they are good learners. Honey bees can learn associations between novel, compound visual stimuli (Schubert et al 2002) and, as mentioned above, they can also do second-order conditioning on olfactory stimuli (Hussaini et al 2007). But can they do second-order conditioning on novel, compound stimuli?…”

“…The upshot is increasing optimism about the idea that science is ready to confront the puzzles of animal consciousness in a serious way, and to start making evidencebased assessments about which non-human animals are conscious and which are not (Boly et al 2013;Le Neindre et al 2017). This seems clearly correct in relation to non-human mammals.…”

“…Our fellow mammals have a cortex like ours (albeit smaller), and the (thalamo)cortical mechanisms supporting consciousness in their brains are likely to be close homologues of those supporting consciousness in ours. It is a straightforward question whether those mechanisms are there or not, and the evidence so far strongly suggests that they are (Boly et al 2013;Le Neindre et al 2017).…”

Bien-être animal : contexte, définition, évaluation

“…L'expertise collective conduite par l'Inra sur la conscience animale définit la conscience comme « l'expérience subjective, ou phénoménale, que les animaux ont de leur environnement, de leur propre corps et/ou de leurs propres connaissances » (Le Neindre et al, 2017). Elle permet de caractériser la façon dont l'animal ressent la situation qu'il vit.…”