On this thread, @Mij found an interesting link to the MdDS Foundation (Mal de Débarquement Syndrome Foundation). MdDS is a kind of dizziness that feels like "bobbing" and swaying back and forth, as opposed to the "spinning" of vertigo. This is the same type of dizziness I experienced at ME onset and for many years thereafter. The French name of the syndrome refers to the "sickness from disembarkation," or the unsteadiness one experiences when getting off of a long journey by boat, train or other conveyance which is in constant motion. The process of returning to normal balance is often referred to as getting your "land legs" back. In people with MdDS, this feeling of bobbing and swaying can last for years. In this 2014 paper, doctors at Mt. Sinai School of Medicine, New York, apparently found a remarkably effective cure for MdDS. This finding was also discussed here: https://www.eurekalert.org/pub_releases/2014-08/tmsh-nt080714.php Basically, they put you in a chair in a circular room that has projected, vertical bars spinning around the walls. This gives you a sense of rotating in the opposite direction to the spin of the bars. They then rotate your head +/- 20 degrees on the forward pointing axis. They do this for 3-5 minutes, 1-8 times a day, for 5 days. That's it - although it might not be very pleasant for someone who already has dizziness. I have no idea if this kind of treatment would help with any kind of ME/CFS associated dizziness, particularly that associated with low blood pressure or POTS. On the other hand, it seems as though MdDS can occur without any recognized exposure to traveling / motion. It would seem weird if ME/CFS could somehow mess with the vestibulo-ocular reflex in some patients, but how weird is too weird?