>In the case of C. elegans, despite being a widely studied animal, evidence of their being conscious is weak and their behavioral reactions are simple and highly stereotyped.
What do you mean by simple? Having nociceptors is a good indicator of pain, right? Surely more than a 1% chance, that just seems like crazy overconfidence.
Although the possession of nociceptors is perhaps some evidence of a capacity to feel pain, it is certainly not by itself “a good indicator” of that capacity. If nociceptors are not connected to centralized information-processing structures, these neurons could trigger reflexive reactions (i.e., similar to spinally mediated responses in mammals), but that would not imply that the nociceptive input is consciously perceived (in humans, see Becker et al., 2012; Dubin & Patapoutian, 2010). If we understand consciousness as suitably integrated information (Oizumi et al., 2014), the projections of nociceptors to integrative information-processing structures is a crucial aspect to examine when judging the probability that a nonhuman individual is conscious.
In the case of C. elegans, unlike other invertebrates, they do not seem to have a specific neural region for the processing of spatial information and organization of movement. In other words, movement and stimuli discrimination do not appear to be integrated in a manner sufficiently similar to the vertebrate midbrain (see Altun & Hall, 2011; Kato et al., 2015).
However, it should be noted that some noxious stimuli reactions have been identified in C. elegans, specifically, physiological responses to nociception and moving away from a noxious stimulus. However, heat-evoked escape responses in these animals, for example, are considered highly stereotypical, and a reflexive reaction (Leung et al., 2016).
Finally, when I used the term “simple” [nociceptive behaviors] here I specifically meant: (i) nociceptive responses can be identified, but they do not necessarily account for noxious stimulus intensity and direction, (ii) absence or insufficient indicators of ‘long-term’ learning and memory, and (iii) absence or insufficient indicators of motivational tradeoffs. Given our findings (summarized here), C. elegans seem to mostly display simple nociceptive responses.
>In the case of C. elegans, despite being a widely studied animal, evidence of their being conscious is weak and their behavioral reactions are simple and highly stereotyped.
What do you mean by simple? Having nociceptors is a good indicator of pain, right? Surely more than a 1% chance, that just seems like crazy overconfidence.
Hi!
Although the possession of nociceptors is perhaps some evidence of a capacity to feel pain, it is certainly not by itself “a good indicator” of that capacity. If nociceptors are not connected to centralized information-processing structures, these neurons could trigger reflexive reactions (i.e., similar to spinally mediated responses in mammals), but that would not imply that the nociceptive input is consciously perceived (in humans, see Becker et al., 2012; Dubin & Patapoutian, 2010). If we understand consciousness as suitably integrated information (Oizumi et al., 2014), the projections of nociceptors to integrative information-processing structures is a crucial aspect to examine when judging the probability that a nonhuman individual is conscious.
In the case of C. elegans, unlike other invertebrates, they do not seem to have a specific neural region for the processing of spatial information and organization of movement. In other words, movement and stimuli discrimination do not appear to be integrated in a manner sufficiently similar to the vertebrate midbrain (see Altun & Hall, 2011; Kato et al., 2015).
However, it should be noted that some noxious stimuli reactions have been identified in C. elegans, specifically, physiological responses to nociception and moving away from a noxious stimulus. However, heat-evoked escape responses in these animals, for example, are considered highly stereotypical, and a reflexive reaction (Leung et al., 2016).
Finally, when I used the term “simple” [nociceptive behaviors] here I specifically meant: (i) nociceptive responses can be identified, but they do not necessarily account for noxious stimulus intensity and direction, (ii) absence or insufficient indicators of ‘long-term’ learning and memory, and (iii) absence or insufficient indicators of motivational tradeoffs. Given our findings (summarized here), C. elegans seem to mostly display simple nociceptive responses.