Waneeno and I spent a fair amount of time trying to figure out just what these did. Nothing is for certain, in fact, far the other way around, but if I remember right (this was back in may)....
Insecure would cause a mob to 'flee' sooner in the fight, IE at 20% instead of 10%.
Pressured -
Defensive would stop them from fleeing. This might have been a fluke, but twice while I was training ID, defensive caused a fleeing mob to turn around again and throw hands.
It's all just (very bad) speculation, but that's all I remember finding for those :/