Patient: Iam a woman 53 years of age. recently I have had to strange episodes. Once I woke up at night and I felt tingling on the left side of my toungue. After a few minutes that side became numb and I had difficulties in speaking. I took atenolol and went back to sleep. The next day it had subsided and by the midday I could speak normally again. Yesterday I woke up in the morning with the same symptoms but were mild. What could this be ?