A neural correlate of sensory consciousness in a corvid bird

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Science  25 Sep 2020:
Vol. 369, Issue 6511, pp. 1626-1629
DOI: 10.1126/science.abb1447

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  • RE: Avian prefrontal cortex and conscious experience
    • Jesper Mogensen, Professor, The Unit for Cognitive Neuroscience (UCN), Department of Psychology, University of Copenhagen, Denmark
    • Other Contributors:
      • Morten Overgaard, Professor, Aarhus Institute of Advanced Studies, CFIN

    Nieder et al (1) report interesting electrophysiological data with implications for the understanding of the avian prefrontal ‘cortex’. For almost forty years it has been known that such a structure exists (2) and like in mammals there has been a focus on ‘delay tasks’. Nieder et al (1) adds significantly to the understanding of how the posterodorsolateral neostriatum contributes to the mediation of such tasks.

    The authors, however, also interpret their single cell recordings to reflect subjective perceptual awareness – and state that their results demonstrate subjective consciousness in birds. Such an approach presupposes that the neural correlate of consciousness (NCC) was identified as a specific and localised activity. Some studies have indicated that prefrontal structures may be involved in the NCC (3) – but that is far from always the case (4). In fact, some of the maybe best supported models of the NCC (5, 6) operate with a NCC that is focused on computational principles rather than any specific structure.

    From a theoretical perspective, NCC models based on computational principles would find it more plausible that consciousness is widespread in the animal kingdom than theories that identify consciousness with a specific neural region in e.g. the human brain. Some theories would even expect subjective experience in insects. Thus, the idea of avian consciousness is not foreign to computational models.

    For the very same reason, however, we find...

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    Competing Interests: None declared.
  • RE: Isn't there some missing logic here?

    In a fascinating article, Nieder, Wagener, and Rinnert (25 September 2020) find a neural correlate of a corvid’s reported perception of a near threshold stimulus. The correlate is not present at time of stimulus presentation but is present during a delay period. They take this finding as evidence of consciousness in the corvid, as it is a correlate of “one reported perceptual state versus the other for equal visual stimuli.” Surely something is missing here, some critical piece of logic. A corollary of their logic is that in the case of no consciousness there would be no neural correlate. So, conscious mental activities arise from neural processing, but unconscious mental activities arise deus ex machina?

    Nieder, A., Wagener, L., & Rinnert, P. (25 September 2020). A neural correlate of sensory consciousness in a corvid bird. Science, 369(6511), 1626 - 1629.

    Competing Interests: None declared.
  • RE: please stop the illogical rhetoric
    • Selmer Bringsjord, Prof of: Cognitive Science; Computer Science; Logic & Philosophy; Management & Technology, Rensselaer Polytechnic Institute (RPI)

    The lead-in to the Nieder et al. paper, verbatim, includes:

    "Humans have tended to believe that we are the only species to possess certain traits, behaviors, or abilities, especially with regard to cognition. Occasionally, we extend such traits to primates or other mammals—species with which we share fundamental brain similarities. Over time, more and more of these supposed pillars of human exceptionalism have fallen."

    Respectfully, this borders on the outright preposterous, for innumerable reasons; here are three.

    (R1) The cognitive exceptionalism of human persons is secured by the fact that such agents have command of formal and natural languages sufficient to not only describe the operation of Turing machines, but machines more powerful than Turing machines (e.g. infinite time Turing machines). This is an utterly untouchable-by-nonhuman-animals pillar. (Birds, corvids or otherwise, communicate in languages that are /below/ Type 0 grammars.)

    (2) The cognitive exceptionalism of human persons is secured by the fact that such agents have command of abstract inference schemata without which theorems in mathematics even at the high-school level cannot be obtained. A simple example is the schema of mathematical induction on the natural numbers, an infinite set. This is an utterly untouchable-by-nonhuman-animals pillar.

    (3) Turning specifically to consciousness and Nieder et al., no reasonable proponent of our cognitive excepti...

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    Competing Interests: None declared.
  • RE: Consciousness, corvids, and thermostates

    A recent article (1) claims that undoubtedly-excellent experimental work in perceptual and behavioral neuroscience reported therein can be interpreted as evidence for ‘consciousness’ in nonhuman animals. Unfortunately – as is frequently the case in this field – the appeal to the word ‘consciousness’ is at best unclear. Non-expert readers should be made aware that the methodological approach adopted in (1) would show that a thermostat is in ‘conscious’ control of a heating system: objectively-observable states of a representational sub-system (brain or thermostat) correlate with objectively-observable states of an action sub-system (body or heater).

    Nieder et al. suggest that ‘whether … “phenomenal consciousness” … can and should be dissociated from … “access consciousness” … remains intensely debated.’ This wording may lead non-experts to infer that the default scientific stance should be non-dissociation, or even identity. But there is currently no scientific evidence (other than subjective human belief) that the phenomenal-consciousness/report relationship can even be investigated scientifically. If conscious experience is a passive brain-property with no dynamical sequelae, third-party attributions of in-experiment reports to subjective experience have no assumption-free scientific basis [2]. Then, studies of report (including non-verbal behavior) can’t establish scientific information about subjective experience – including its relationship to report. Inability...

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    Competing Interests: None declared.

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