This is what I awoke with, cogitating through closed eyes, groggy from some medicine I took last night, a grogginess which will not leave me, and so I share my points as point-by-point. I confess I'm feeling very clever right now, my head-full-of-cotton notwithstanding.
1. Preface: I'm not doing any additional research, so any one of these points could be proven wrong, with a simple reference to the Incredible Hulk's long history, biology, or intelligent design argumentation. I still boldly go, intuitively raining my brilliance upon the Nation of Facebook.
2. Let us proceed, for a bit, to reason from a scientific mindset.
3. When Bruce Banner becomes the Hulk, he gets a lot bigger, stronger, and less intelligent, more simple in choosing the factors upon which he chooses to act. He converts from brilliant scientist to freakish huge green cave-thingie.
4. When this happens, do certain neural pathways gently unplug themselves from each other? As the body grows, do the synapses fail to grow along with the skeleton, the muscles, the skin? I propose something like this must happen. Just as his clothing remains on his body, even though in the comics he sometimes grows ten times his size, this so he doesn't show his big green penis to the millions of ten-year-olds who used to read his comic book, so must his synapses remain undamaged. So it must be a gentle process he undergoes, which allows him to return to the status of Scientific Smart Person at some point with all of his cognitive abilities reinstated as if nothing had happened.
5. Furthermore, "Hulk smash" is not similar to how any two-year-old I've met speaks. Nobody talks like that. So this is not a cognitive reversion to childhood. Maybe it is literary (more on that in a moment) device to show that he is becoming more like a beast than a man, but scientifically speaking, that is not allowed. Hulk's linguistic change is not deterioriation - he loses weird things, like prepositions, and verb tenses, and commas. And when he shrinks back down in size and becomes Banner again, he's able to speak normally again.
6. We should note that, while there appears to be a connection with whatever keeps his close from ripping completely off his body and whatever the heck happens to his neural network, the difference is obvious: he does lose his shirt and the lower-leg portion of his purple pants do end up shredded. The only parallel I can see is that Banner's Hulkifying does damage to his conscience and his social life, so maybe I'm onto something there. That appears, however, to be literary rather than biochemical.
7. (Speaking of literary, and films are considered part of literary study these days, while Banner might feel fortunate that he doesn't always emerge from Hulkdom completely naked, werewolves in movies and TV do not share that luck. Of course, that makes this viewer happy, as there are so many hot actors playing werewolves and it's always nice to see them completely naked. The exception I must note is the second Twilight film - I haven't seen the third, as the second was terrible but I can't help it, I have a Robert Pattinson attraction as big as the Hulk himself - in which the actors are underaged, and the world is paranoid about underaged nudity these days, in spite of the irony of the focus on a gang of muscled teenage boys running around shirtless certainly having some element of sexual intent behind it.)
8. Most of what I've observed, excluding #7, which is True and not False, would certainly not match what scientists have observed thusfar in the natural world. Unless, like with the extra-terrestrial crash-landing at Roswell, they are keeping it a secret from us, scientists have most likely not observed a human turn into a very large creature with strange verbal skills return to his normal state with his former intelligence and verbal acuity regenerated.
10. Bruce Banner has regenerative powers, and the gamma-ray blast gave those to him along with everything else, or
11. God exists as an intelligent designer, and Darwin worshipped Satan.
Note: is the Bruce Banner/Hulk dichotomy the two sides of Jesus, both God and Man? Or something more complicated, like Jesus and Herod?