The majority of investigations of human consciousness have relied on “accurate reports”, supplied by healthy or brain-damaged individuals, of what they experienced during experimental trials. In species without natural language, however, acquisition of accurate reports of conscious contents presents a major challenge. But now, timely advances in functional neuroanatomy, neurophysiology, and genetics offer the possibility of exploring consciousness substantively and systematically in non-human mammals, birds, and possibly other species as well. In this symposium, recent research in animal cognition relevant to consciousness will be highlighted by three invited speakers whose efforts extend the state of the art. The co-organizers will describe a methodological framework for the investigation of animal consciousness that incorporates the speakers’ findings; finally, a speculative phylogeny of animal consciousness will be proposed with the aim of stimulating future investigations of consciousness in species far removed from the human, mammalian, or even vertebrate, lines.
For almost 30 years I have studied cognitive and communicative abilities of Grey parrots. Although I do not examine consciousness directly, my research seeks to answer questions related to consciousness: (1) To what extent can a nonhuman, nonprimate (with a brain the size of a shelled walnut) share mental capacities, representations, and comprehension with humans? (2) To what extent, and at what level, do mechanisms of cognition and communication exhibited by this avian species resemble those operating in humans? (3) To what extent, and for what innate purpose, have such avian abilities been developed? (4) Can the study of mechanisms for vocal learning in the laboratory help us understand human vocal learning; that is, can an avian subject be a model for human processes? My data, showing that, on some tasks, Grey parrot abilities match those of young children, suggest that these birds are viable candidates for more advanced study.
The general plan of the vertebrate brain is highly conserved in
phylogeny, such that its principal subdivisions and fiber tract circuitry can be homologized across widely different species throughout the vertebrate clade. An issue of fundamental importance for our understanding of animal consciousness is accordingly whether a “mechanism of consciousness” might be implemented as part of this conserved circuitry – which would mean that all vertebrates are conscious creatures – or whether consciousness is a matter of specializations added to this circuitry in some species – say the mammalian novelty of a neocortex – but absent in others. In my presentation I will outline conceptual approaches to this question drawing on a characterization of minimal requirements for conscious function on the one hand, and on conjectures regarding the role and organization of such a functional mode within the over-all economy of brain macrosystems on the other. Implications of this perspective for the larger issue of the possibility of consciousness in invertebrate animals will also be considered.
The cephalopod mollusc, Octopus vulgaris, an invertebrate, has been long considered a learning animal exhibiting an enriched behavioral repertoire of comparable complexity with the one recognizable in higher vertebrates up to humans. I will review briefly almost a century of research effort dedicated to the understanding of its learning capabilities and the underlying neural correlates. In reviewing this history we will be faced with limits in the capabilities of octopuses such as the lack of kinaesthetics. I will try to show that these "limits" are weak and that the octopus should be considered a model to test properties such as parallel processing, sensorial independence and hierarchical organization of motor control, "self perception".
This with the aim to show that the octopus, an invertebrate, is an experiment in the phylogeny that may allow us to ask questions on consciousness in animals.