Forum:Thrór madness

Hi!

After watching the new Peter Jackson Hobbit movie I was left a bit confused about their portrayal of Thrór. It was mentioned how the dwarves of Erebor amassed great wealth. I would come to the conclusion that it was this act that attracted dragons, especially Smaug.

Furthermore it was mentioned that he would suffer from "sickness of mind" and that it would lead to unfortunate events. I have had trouble finding any information regarding this on this wiki and elsewhere. Did Thrór become mad? Did it have any impact on the dwarves of Erebor before and after the arrival of Smaug?