Throughout my life frlom time to time I suddenly have these what you may or may not call mild seizures where I incontrolably shudder, I have to shake my head from side to side and it usually involves some form of vocal release, sort of like when you take a shot of tequila and a slice of lem, that kind of thing. I don't know what causes it, or whether its consider a form of epilepsy or not, I have never spoken to a doctor or anyone about, nor felt the need to as it has never ever caused me any distress, pain or any problem whatsoever.