Stroke and Seizure

My dad has a three strokes in the past eight years and he just recently have one this week including a seizure.  He is in a critical condition where both side of his brian was damage due to the first three strokes that occur on his right side of the brain and the new stroke that now occur on his left side.  Also the doctor told us that the seizure was cause by the scar tissue from his left side of the brain from his previous three strokes.  Now, the doctors are saying that he is in a coma.  In the past few days, he was able to open up his eye in every 10 to 20 minutes but he still has the seizure and the doctor are saying that he still in a coma.  However, I saw him blink his eyes a few times, but he has not respond to anything.  I was curious that if the neruon cells were damage in his brain, is it possible for it to recover? Also, if he was to recover, will he lose all of his memory since both side of the brain was damage?