TPP1 and movement disorder: CLN2-disease natural history has been characterized using functional scales, typically either Hamburg (modified to CLN2-Disease Rating Scale) or Weill-Cornell, which focus on seizures, ambulation, language, and visual function.2,4,6 Some movement disorders are well-recognized: ataxia is an early hallmark contributing to loss of ambulation; myoclonus is almost universal representing both epileptic and nonepileptic movements.2 Other movement disorders such as chorea, tremor, and dystonia are less well characterized.