Question

If you know bout this please help me out

Answer 1

It would most likely be memory performance because that is what it is trying to tell you to take care of and if not it would be the brain. However, it talks about the memory specifically so it should be that. 

Answer 2

I think it might be memory performance since that was in the introduction sentence and throughout the paragraph. My second guess would be the brain since much of the paragraph talked about the brain.