What Causes Loss Of Memory And Feeling Of Confusion?

Hi.my husband is 53 yrs and he is active in all the way.but last year suddenly after morning prayer he fell on the cooler while offering prayer and was bleeding and fainted when he got up andcame home from mosque we asked how it happened but he said i dont kno i dont remeber he is thinking it might due to sleep....we tok him to doctor and he was adviced for CT scan but everything was normal..after few days he started 4getting past things or some times present things too...and now he is very much pizzed sometimes ..can u help me out thank u