sleep/ jumping around all night

[seafly]

I am stopping my wife from sleeping properly because I am leaping and jerking around. She says I do this virtually all night, within half an hour of dropping off and continue for most of the night. I've been doing it for about 2 years now and I am thoroughly unaware whilst it is happening. It isn't affecting ME at all !!! Does anyone know what causes it and how it can be stopped? My doctor doesn't have any answers