Everytime I do it my brain capacity decrease.

I am not joking. I am in really advanced math and engineering class and I swear I work less well after relapsing. Not only that but I feel dumber. After relapsing I am always having a harder time with maths (usually one of my strength). English too, it is not my first language and I speak more fluently when I don’t watch porn for a long time. Nature blessed me with a high intellectual capacity, yet I am dumb enough to not take care of it. I am getting dumber (at least temporarily) and I must not fail again.