How does alcohol actually affect the brain?

So I heard from one of my friends that alcohol can damage the brain, but as soon as I looked it up I found a vast array of mixed view points regarding the topic. So can getting drunk occasionally (lets say like once a month) damage your dendrites or brain cells? Also is this damage permanent or can it be repaired by the standard regulatory processes that occur in the brain. If it is permanent I don't understand how there are so many brilliant people around me who still retain their intelligence even though they drink and party often. Right now I'm just worried if I should even continue to drink or how much I should limit myself to. I'm a college student btw.