Autonomic Nervous System DiseasesDiabetic NeuropathiesAutonomic Nervous SystemHeart RateCardiovascular DiseasesValsalva ManeuverHypotension, OrthostaticAdie SyndromeMultiple System AtrophyShy-Drager SyndromeVagus Nerve DiseasesBaroreflexTilt-Table TestPrimary DysautonomiasReflex, AbnormalPseudoephedrineElectrocardiography, AmbulatoryDiagnostic Techniques, NeurologicalBlood PressurePostural Orthostatic Tachycardia SyndromeTonic PupilCardiovascular SystemDysautonomia, FamilialPosture3-IodobenzylguanidinePain Insensitivity, CongenitalArrhythmia, SinusPolyneuropathiesHeartElectrocardiographyParasympathetic Nervous SystemGuillain-Barre SyndromeLewy Body DiseaseDizzinessNeuroleptic Malignant SyndromeIodobenzenesHypotensionParkinson DiseaseSympathetic Nervous SystemFludrocortisoneSweatingGalvanic Skin ResponseTachycardiaErectile DysfunctionVentricular Dysfunction, LeftPupilReflexCase-Control StudiesPolyradiculoneuropathyVagus NerveBradycardiaSupine PositionArrhythmias, CardiacAtaxia