One famous television show line went, "You wanna catch a fish? Think like a fish." Since fish have very small brains and believe me I checked. I Talked to three fish researchers at the University of Minnesota, main campus and at UMD and they all pretty much agreed, a very large brain( fish/trout brains are shaped like a small rope with a knot in the middle) in 7 pound trout like we have here in the North is smaller than one peanut or jelly bean. Every fish brain article I have checked goes on to say fish can't think. So while that TV line is clever or cute, it misses the hook set by a wide margin.
Some fish (trout specifically) researchers found that small steelhead hatched in rearing ponds with the simple addition of stones and small rocks to their aquatic environment as yolk sac fry sized actually enlarged the cerebellum in the trout's brain. It didn't make a bigger brain but the motor skills or movement aspect of the brain increased. This did however make for a better survival rate in stocked fish. This research isn't over yet either.
Do trout/fish feel pain?
Neurobiologists are split brain on this issue. Go figure. A leading consensus however says fish don't feel pain. The University of Wyoming and a University in Liver pool England have some interesting tidbits to pass along. One is that if trout (rainbows in this study) do not have the apparatus in the trout brain for pain reception and fish don't, they cannot feel pain. This is a pretty simple concept according to Wyoming and their research.
Jolly old England went so far as to sting trout with bee venom and the trout rubbed their chins on gravel river bottoms exhibiting what these English researchers called pain. Problem here was no nociceptors (big word) fired in the trout brain. They may have done the same thing with too much maple syrup injected. Reaction yes, but pain, they can't distinguish. No fish thinking going on here, just reaction.
So why do fish (trout) react the way they do when we set the hook? Answer, according to all I read in the simplest form is, fish don't want to go the way were pulling them. Fight or flight and their lack of brain intellect as researchers know or are aware, only allow for the most basic flight response. Remember, fish can't talk or think (Not at all close to what humans are capable of).
As humans we tend and sometimes try to get everything on earth humanized. So how is a trout close to humans? In more ways than not, their not. They are fish. So the simple minded fish is once again simply having reactions. So you wanna catch a fish? Don't think like a fish, just go fishing.

The trout whisperer
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