forget what you think a migraine is - it’s not a headache. it’s a brain inflammation of some kind, that produces weird side effects (which can include pain or nausea, but doesn’t have to). one of those side effects can be dizziness/imbalance/sense of motion when it’s a brainstem migraine (that’s the theory at least).
[episodic] migraine attacks can last up to 2-3 days. so if you have one attack every day or every 2-3 days (i.e. like chronic migraine) you will constantly have symptoms, sometimes better, sometimes worse. never goes completely. and you can have symptoms like photophobia for a long time in between attacks.
there’s no such thing as compensation with pure MAV: the symptoms fluctuate with each attack, so there’s no way the brain can compensate against a moving target. however, what it does do is learn to rely on one input, usually vision, to tell itself which way is really up, and where it’s really moving. so you can quite often become visually dependent - your actual balance will improve, and the sense of motion can start to reduce, because your brain is getting conflicting signals from eyes, ears and body, so it shuts off the ears, and just uses the eyes.
medications can help. nobody really knows how or why they help, but they really can help. I’ve been on pizotifen 6 months and it helps a lot. not cured, but much much better than i was. going to add in gabapentin from tomorrow - see where i get to.
i have never had a bad migraine headache. i have had just about every other migraine symptom - visuals, photophobia, phonophobia, nausea, dizziness, weakness and bad coordination in legs, tinnitus, weird head sensations, some head pains and occasional bit of headache behind left eye but never classic really painful headache.
i am pretty sure i have MAV. there’s nothing actually wrong with my balance - i can ride my mountain bike on a good day down some pretty challenging trails - but i have sense of motion when i get off the bike. i definitely feel the episodes starting - starts with tinnitus first, then goes through the spectrum of symptoms. but it’s always there to some extent. My dr (Dr S) says i’ll know i’m getting truly better when i start having normal days in between the episodes - i.e. you get fewer attacks, further apart.
i hope some of this is helpful. it’s a hard condition to understand.