Myoclonus is a twitching or spasm of a group of muscles. Sorry to state
what you so obviously know, but we want to be discussing the same thing.
Palatal myoclonus (often just called myoclonus) is a problem that
involves the paramedian branches of the Superior pontine, a nucleus in
the medulla. Structures involved I would suspect to be arcuate fibres.
Hope this helps.
