Rose, James D. (2016) Pain in fish: Weighing the evidence. Animal Sentience. 3(25)
Brian Key, Why fish do not feel pain
The target article by Key (2016) examines whether ﬁsh have brain structures capable of mediating pain perception and consciousness, functions known to depend on the neocortex in humans. He concludes, as others have concluded (Rose 2002, 2007; Rose et al. 2014), that such functions are impossible for ﬁsh brains. This conclusion has been met with hypothetical assertions by others to the effect that functions of pain and consciousness may well be possible through unknown alternate neural processes. Key's argument would be bolstered by consideration of other neurological as well as behavioral evidence, which shows that sharks and ray are ﬁshes that have no nociceptive afferents and that bony ﬁshes, although they have A delta nociceptors, are extremely deﬁcient in C ﬁbers, the most abundant nociceptor in mammals. In addition, behavioral studies of surgery, angling and other putatively noxious procedures show that ﬁsh don't behave as if they suffer from pain.