I have been getting a mild and quick on/off sensation in my brain when I wake up during the night for a few weeks.  This seems to be rest related and is  not painful.  It doesn't happen every night but when it happens it may last a couple of minutes and I will have several on/off sensations.  I am healthy, 60 years old, have high blood pressure which is managed well with medication,exercise several times a week and eat fairly healthy diet. I do have migraines, sometimes complex migranes but they are rare since I have retired.  Does anyone else experience this?