nystagmus with palatal, tongue, and mandibular movements called oculomasticatory myorhythmia has been considered pathognomonic.
[jnnp.bmj.com]
Upbeat nystagmus changing to downbeat nystagmus with convergence. Neurology. 1981;31(7):891–892. doi:10.1212/wnl.31.7.891 43. Shorey J, Bhardwaj N, Loscalzo J.
[dovepress.com]
[…] typically, at least initially, supranuclear in type), myoclonus, and various hypothalamic features including insomnia, hyperphagia, and polydipsia.91 92 The combination of convergence
[jnnp.bmj.com]