nAChR (Nicotinic AcH receptors)

I'm kind of boggled right now with my EK Bio2 lecture 2 exam. There's a passage with a study that says that "nicotinic acetylcholine receptors (nAChr) causes the hyperpolarization" then theres a question where they ask you would would happen to a smoker with Myasthenia gravis disease that basically blocks acetylcholine receptors. In sum, the reasoning behind the question is to realize that blocking the receptors would lead to depolarization.

However, I thought NICOTINIC acetylcholine...

nAChR (Nicotinic AcH receptors)