Animal consciousness: A synthetic approach

The Neurosciences Institute, 10640 John Jay Hopkins Drive, San Diego, CA 92121, USA.
Trends in Neurosciences (Impact Factor: 13.56). 09/2009; 32(9):476-84. DOI: 10.1016/j.tins.2009.05.008
Source: PubMed


Despite anecdotal evidence suggesting conscious states in a variety of non-human animals, no systematic neuroscientific investigation of animal consciousness has yet been undertaken. We set forth a framework for such an investigation that incorporates integration of data from neuroanatomy, neurophysiology, and behavioral studies, uses evidence from humans as a benchmark, and recognizes the critical role of explicit verbal report of conscious experiences in human studies. We illustrate our framework with reference to two subphyla: one relatively near to mammals - birds - and one quite far -cephalopod molluscs. Consistent with the possibility of conscious states, both subphyla exhibit complex behavior and possess sophisticated nervous systems. Their further investigation may reveal common phyletic conditions and neural substrates underlying the emergence of animal consciousness.

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Available from: David B Edelman,
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    • "On the one hand, it is generally believed that the basic structure for the emergence of consciousness is mainly the thalamocortical system as a whole, with a specifically important role played by the prefrontal, cingulate and parietal cortices (Edelman and Tononi 2000; Laureys and Tononi 2009). On the other hand, besides anatomical structures, the fundamental processes of consciousness are cortical connectivity through information integration (Tononi 2008; Edelman and Seth 2009) and elaboration of information shared and processed at a global level (Dehaene and Changeux 2011; Tononi and Koch 2008). "
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    ABSTRACT: The problem of animal consciousness has profound implications on our concept of nature and of our place in the natural world. In philosophy of 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 the phenomenological question (“what is it like to be a non-human animal?”). In order to answer these questions, many approaches take into account similarities and dissimilarities in animal and human behavior, e.g. the use of language or tools and mirror self-recognition (Allen and Bekoff, 2007), however behavioral arguments don’t seem to be conclusive (Baars, 2005). Cognitive neuroscience is providing comparative data on structural and functional 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 structure of thalamocortical system remained the same in the last 100-200 million years, for it is neuroanatomically similar in all the present and past mammals and it didn’t change much during phylogeny (Allen and Bekoff, 2007). The argument from analogy states that the key functional processes correlated with consciousness in humans are still present in all other mammals and many other animals (Baars, 2005). These processes are 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 Cambridge Declaration on Consciousness states that all mammals, birds, and many other animals (such as octopuses) possess the neurological substrates of consciousness (Low et al., 2012). Conscious experience is private (Chalmers, 1995; Nagel, 1974) therefore the answer to the phenomenological question may be impossible. Nevertheless, cognitive neuroscience may provide an answer to the distribution question, showing that conscious experience is not limited to humans since it is a major biological adaptation going back millions of years.
    Naturalism and Constructivism in Metaethics, Edited by Sofia Bonicalzi, Leonardo Caffo, Mattia Sorgon, 05/2014: pages 182-203; Cambridge Scholars Publishing., ISBN: 978-1-4438-5673-7
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    • "goal-directed processes ), keeping the contents of ROM (i.e., habitual responses) hidden deep within the " black box " and inaccessible to consciousness . This analogy also is consistent with the notion that subjective consciousness is not a capacity that divides humans from other animals: instead, it is present across many mammals, birds and even invertebrates (Edelman and Seth, 2009; George and Hawkins, 2009). Importantly, we are not suggesting that the human brain requires a " ghost in the machine " to work effectively , rather that important aspects of conscious experience can be conceptualized as the degree of access that an organism has to its' competing memory systems. "
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    ABSTRACT: The ability to delegate control over repetitive tasks from higher to lower neural centers may be a fundamental innovation in human cognition. Plausibly, the massive neurocomputational challenges associated with the mastery of balance during the evolution of bipedality in proto-humans provided a strong selective advantage to individuals with brains capable of efficiently transferring tasks in this way. Thus, the shift from quadrupedal to bipedal locomotion may have driven the rapid evolution of distinctive features of human neuronal functioning. We review recent studies of functional neuroanatomy that bear upon this hypothesis, and identify ways to test our ideas.
    Frontiers in Neuroscience 04/2014; 8(8):90. DOI:10.3389/fnins.2014.00090 · 3.66 Impact Factor
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    • "Similar neuronal mechanisms might support a level of consciousness across mammalian species in general, given brain structures and circuitry that are closely homologous to the human case, conserved neurophysiological signatures during sleep states and general anesthesia, and comparable behavior (Edelman, Baars et al. 2005; Edelman and Seth 2009). Beyond mammals, however, this argument is more difficult to make, primarily owing to an incomplete understanding of the relevant neuroanatomy and neurophysiology. "
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    ABSTRACT: This joint article reflects the authors' personal views regarding noteworthy advances in the neuroscience of consciousness in the last 10 years, and suggests what we feel may be promising future directions. It is based on a small conference at the Samoset Resort in Rockport, Maine, USA, in July of 2012, organized by the Mind Science Foundation of San Antonio, Texas. Here, we summarize recent advances in our understanding of subjectivity in humans and other animals, including empirical, applied, technical, and conceptual insights. These include the evidence for the importance of fronto-parietal connectivity and of "top-down" processes, both of which enable information to travel across distant cortical areas effectively, as well as numerous dissociations between consciousness and cognitive functions, such as attention, in humans. In addition, we describe the development of mental imagery paradigms, which made it possible to identify covert awareness in non-responsive subjects. Non-human animal consciousness research has also witnessed substantial advances on the specific role of cortical areas and higher order thalamus for consciousness, thanks to important technological enhancements. In addition, much progress has been made in the understanding of non-vertebrate cognition relevant to possible conscious states. Finally, major advances have been made in theories of consciousness, and also in their comparison with the available evidence. Along with reviewing these findings, each author suggests future avenues for research in their field of investigation.
    Frontiers in Psychology 10/2013; 4:625. DOI:10.3389/fpsyg.2013.00625 · 2.80 Impact Factor
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