I have really low blood pressure, so I get these if I stand up too quick from sitting or laying down. Or... sometimes everything just goes black for a bit. If you tend to see these doing rolls, maybe you should try spotting. Keep your eyes focused on uke as you roll at some point, you will have to turn your head, but dances have to do this as well. You will end up coming to your feet and turning to face them to maintain the eye contact. This photo from Potomac Aikikai (I believe) is a decent photo of this. I found one wihle browsing sites yesterday that was perfect, but I can't seem to find it now....