Bed RestHead-Down TiltWeightlessness SimulationWeightlessness CountermeasuresRestCardiovascular DeconditioningSensationSpace FlightBedsAcoustic StimulationPhysical StimulationPhotic StimulationWeightlessnessAction PotentialsReaction TimeNeuronsTouchModels, NeurologicalOrthostatic IntoleranceAuditory PerceptionVibrissaeEvoked Potentials, AuditoryDiscrimination (Psychology)Time FactorsElectric StimulationAuditory CortexSomatosensory CortexVisual PerceptionBehavior, AnimalBrain MappingLower Body Negative PressureOdorsEvoked Potentials, SomatosensoryDiscrimination LearningNeurons, AfferentNerve NetThalamusMacaca mulattaEvoked PotentialsNeural InhibitionEvoked Potentials, VisualCuesVisual CortexNeural PathwaysHabituation, PsychophysiologicAfferent PathwaysAttentionSensory Receptor CellsSensory ThresholdsCerebral CortexAnalysis of VarianceSmellElectric FishElectroencephalographyAmygdalaMagnetic Resonance ImagingPsychomotor PerformanceElectrophysiologyConditioning, OperantBed OccupancyAdaptation, PhysiologicalInterneuronsCatsBrainTasteRats, Long-EvansMuscle, SkeletalOlfactory PathwaysParietal LobeMotion PerceptionNeuronal PlasticityMacacaElectrodes, ImplantedConditioning (Psychology)Reinforcement (Psychology)Conditioning, ClassicalMuscular AtrophySupine PositionRewardConsciousnessSuperior ColliculiSynaptic TransmissionVisual PathwaysLearningWakefulnessPlasma VolumeExerciseMemoryEarly AmbulationStartle ReactionFunctional LateralityGeneralization, StimulusSpace PerceptionElectromyographyRats, Sprague-DawleyHypotension, OrthostaticVibrationSynapsesPerceptionHypovolemia