Multiple System AtrophyCerebellar AtaxiaOlivopontocerebellar AtrophiesShy-Drager SyndromeSupranuclear Palsy, ProgressiveAtrophyAtaxiaalpha-SynucleinSpinocerebellar DegenerationsAutonomic Nervous System DiseasesParkinson DiseaseSpinocerebellar AtaxiasPutamenSynucleinsHypotension, OrthostaticGait AtaxiaInclusion BodiesLewy Body DiseaseMidodrineThioninsParkinsonian DisordersFriedreich AtaxiaDiagnostic Techniques, NeurologicalStriatonigral DegenerationCerebellumParkinson Disease, SecondaryPure Autonomic FailureVocal Cord ParalysisLewy BodiesTonic PupilBrainMagnetic Resonance ImagingOligodendrogliaBrain StemExtrapyramidal TractsRecurrent Laryngeal NerveSweat Gland DiseasesAge of OnsetNerve Tissue ProteinsMuscular AtrophyREM Sleep Behavior DisorderCerebellar DiseasesAtaxia TelangiectasiaNeurodegenerative DiseasesNeurologic ExaminationNerve DegenerationOptic AtrophyLevodopaAutonomic Nervous SystemBasal GangliaLaryngoscopyEphedrineMachado-Joseph DiseaseElectromyographyAntiparkinson AgentsDihydroxyphenylalanineGenes, RecessiveStiff-Person SyndromePedigreeMyoclonic Cerebellar DyssynergiaPonsPerineumReflex, AbnormalUrodynamicsTrinucleotide RepeatsSeverity of Illness IndexSalicylamidesApraxiasPurkinje CellsCaudate NucleusNeuronsSubstantia NigraGenes, DominantDeath, Sudden