I Have Very Brief (usually Under A Minute) Episodes Of

I have very brief (usually under a minute) episodes of extreme vertigo where the entire room spins violently. They are NOT positional. They do NOT occur with movement, I could be sitting still talking or sitting at my desk working or driving in a car. It is usually followed by a feeling of a muffled fullness inside my head, or an odd feeling in my neck up into my head.......And usually just a disjointed feeling and nausea and just not feeling right which can last for a few hours. It used to happen to me On occasion a year or so ago, and went away for months and now started again. I've had MRI of brain a few years ago that showed multiple lesions that they suspect were caused by migraines I used to get years ago. I'm a 51 yo female. My only med. is Inderal which I've taken over 25 years for mitral valve prolapse and irregular heartbeats, and migraines which are now scarce.