Can fish really feel pain?

This is probably going to be something I return to, but believe it or not there has long since been a debate about whether animals (and even babies) feel pain.

Combine the two of course (puppies) and you have the origins of the practice of tail docking.

Most recently, various media sources including the Telegraph and even the @MRCVSonline Twitter feed published a link to a paper which claimed that fish did NOT feel pain.  It is an old debate, and this is the latest installment of an old theory.  Direct response from fishy expert: Lynne Sneddon (her response is buried in the article comments).
So where does it come from?

The Background on Pain

Well in as un-cynical terms as possible, and technically from a neuroscience point of view, that which people in general would describe as "pain" is broken down into two parts.  The first is called "nociception" (derives from: noxious sensation).  So if you stick a pin in your leg, there are adapted nerves in the skin which detect this attack and they are called "nociceptors".  The response is "nociception" (not pain yet).  So normally, this nociception would be transmitted by nerves up to your brain where you would feel it as pain.  So the brain would be telling you that your arm hurts?  A simple illustration is that if you break your spine and all the nerves are lost not only would you be paralysed, but you would be numb!  You would not feel the pin in your leg.  So if you don't feel the pin... there is no pain!  So "nociception" and "pain" can be separated.  Another way to separate them would be with a local anaesthetic or an opioid pain killer.

Back to Fish

So, back to fish.... if you stick a pin in them, do they register it as pain?  Well... again it is more complex.  They try and escape... and they will thrash about.... so it looks like they are feeling pain, but some people argue that that is just a reflex, like the knee jerk reflex in humans.

...But absolutely any test you do shows what appears to be pain.  Yet, some people continue to reject the idea that fish feel pain.  They argue very confidently, that the areas in the brain which interpret pain are absent in fish (the structure of the fishy brain is a bit different to that of people).  Which is a bit like a man saying "obviously women can't pee because they don't have a penis". Naturally there are a vast array of mechanisms and structures which have adapted through evolution to for fill a vast array of functions and it would take a lot more evidence than this little review to convince me that "pain" just suddenly sprang from nowhere in human evolution!

Here's an idea... perhaps fish feel pain with other parts of the brain.  There are a number of very technical reasons for why it is clear that fish do feel pain in one form or another, but I am not going to go into that here. 

...and strangely, I have little problem with people fishing.
(OK I confess I do fish a little myself, but don't worry I retain the moral high ground by NEVER catching a bloody thing!!)

What I would have a problem with is people fishing and believing that trauma to a fish and apparent pain is NOT pain!  Just catch it and put it out of its misery nice and quick is all I would say!

How about another thing!  Often when one reads real scientific, peer review papers, one looks for the hidden vested interest groups.  The public frequently AND MISTAKENLY think that medical research is funded by BIG PHARMA and (we) do what we are told.  Well, that is not often the case. (I sometimes wish I did have some Big Pharma money to be honest! ), but there may be subtle things, like you published X years ago, and now you have a vested interest in proving that you were right, when people think you are wrong... but just throw back your head a laugh out loud when you realise that this paper claiming fish don't feel pain was published in "Fish and Fisheries" and funded by Fisheries money.  Well "they would say that wouldn't they".

Addendum: Comments from people:
"I couldn't inflict what I would consider pain on any animal, my personal view though."  That is obviously a very worthy and consistent approach.  I suppose it looks incredible that I would contemplate fishing if  I believe that the data says fish feel pain? Well I just like sitting in the sun and watching the world go by.  What has really put pay to fishing for me is the fact my dogs make much greater attempts to snaffle down my baited hook than the fish do.  I find the battle to not injure myself, my dogs or the environment totally puts me off.  I have caught fish for the pot when I was young and I tried to dispatch them as quickly and humanely as possible. If I saw (and I did see) people unbothered by a slowly dying fish... that broke my code and I said so and stepped in to finish the job.  Sorry if that offends anyone: but...  few people argue that chicken, cattle and sheep don't feel pain, but most eat meat.  I don't claim to be a better person than anyone else, I have just tried to explain the situation in as unbiased manner as possible.
"If they felt nothing they wouldn't survive." That is true, of course:  What we are all talking of as pain is an adaptation to facilitate survival.  However, they could be "wired" to have escape reflexes and not actually have capacity to "suffer".  Its starts to get philosophical.  However, before I asserted that any creature didn't feel pain:  I'd want to see a bit of experimental (even if observational) for that!  The paper cited in the Telegraph and elsewhere doesn't seem to have this.  When I was a baby, and I was injured; my father was told me that the medics that stitched me without anaesthetics told him I wasn't screaming and thrashing because I felt pain since the brain was not sufficiently developed yet; I was merely reacting with reflexes.[Hello Dad if you find this!].  Now few people even believe this anecdote, but I told it to the Chair of Medical Ethics in Birmingham University Prof. David Morton and he told me it was a common misconception at that time.