Riker's lucky that the fact his brain shrunk didn't have permanent effects on his mind once he was restored...
One of my guiltiest of guilty pleasure episodes. I remember as a kid thinking it was hilarious how Picard cowers behind Data as de-evolved Worf tries to bust down the door and Data casually says, "it is large". I was watching it recently and it occurred to me (particularly in the 'Caveman Riker' and 'Spider Barclay' scenes) how this episode may be more like a cheesy original "Star Trek" episode more than any other TNG episode. I can't help but think of "Star Trek" when I see the crewmembers acting crazy and the weird make-up/costumes for monsters, albeit in a much darker way than the original series ever did it. I can't decide what is funnier between Riker becoming an idiot who can't finish his sentences and his caveman tantrum.
The script she had to work with wasn't Gates' problem, and I think she did a good job with aspects of it. She got some interesting angles out of the bridge and there were some really atmospheric moments, too.