A perfectly valid question that I look forward to an answer to (assuming one is out there... I mean, I wonder if a squid's axon were damaged, if it could even live long enough to allow it to regenerate....)
Page 50 of Richard Ellis' book on Giant Squid, in reference to Loligo:
A 1988 article on squids by Malcolm Clarke opens with these words: "To many biologists the squid conjures up a vision of an unusually large nerve fibre with graphs issuing from one end while elctrodes are applied to the other." The "unusually large nerve fibre" is another wonder of squid biology, for it can be one-tenth of an inch in diameter, as compared with the largest human axon, which is only one one-thousandth of an inch. The size of these giant axons enables the squid to transmit messages to its musclees substantially faster than any other creature; the squid's ability to respond to a particular stimulus can be almost instantaneous. For human neurological research, these giant axons are much easier to study than those of most other animals.
It is not clear as to whether giant squid have giant giant axons. In his 1977 essay "Brain, Behaviour and Evoloution of Cephalopods," J.Z. YOung (who spent his fifty-year career concentrating on the neurology of squids and octopuses), having disected a specimen that washed ashore in 1933, wrote, "None of the nerves examined contained the exceptional large fibres reported by Aldrich and Brown (1967). We may conclude that Architeuthis is not an especially fast-moving animal. This would agree with evidence that it is neutrally buoyant with a high concentration of ammonium ions in the mantle and arms (Denton, 1974)."
..... yes, even I'm a tad confused (which isn't saying much actually, I'm always confused). There was an article in Nature this past week too .... real pretty pics of developing squid - just don't ask me what language it was written in.
I have a followup question for anyone out there that might know: Does anyone know the diameter of giant and/or colossal squid giant axons? My physiology class is kicking into gear, and I was thinking of a research paper topic. Thanks!
Yeah, me too... I know that the giant axons are nonmyelinated and such, but I would like to know more to calculate conduction velocities and such. We have a paper due by May, and I'm kicking around the idea of doing a paper on squid (mostly because the class tends to focus on vertebrates! )