Circadian RhythmHypothalamusSuprachiasmatic NucleusSleep Disorders, Circadian RhythmPeriod Circadian ProteinsCircadian Rhythm Signaling Peptides and ProteinsCLOCK ProteinsBiological ClocksCircadian ClocksPhotoperiodARNTL Transcription FactorsHypothalamus, AnteriorHypothalamus, MiddleMelatoninChronobiology DisordersActivity CyclesDarknessLightJet Lag SyndromeBody TemperatureCryptochromesHypothalamus, PosteriorSleepMotor ActivityPeriodicityPineal GlandDorsomedial Hypothalamic NucleusVentromedial Hypothalamic NucleusParaventricular Hypothalamic NucleusNuclear Receptor Subfamily 1, Group D, Member 1Arcuate NucleusHypothalamic Area, LateralPreoptic AreaNeuropeptidesNeuronsFeeding BehaviorPhototherapyCasein Kinase IepsilonEatingChronotherapyWakefulnessBrainCorticosteroneRats, Sprague-DawleyTime FactorsBehavior, AnimalLightingHypothalamo-Hypophyseal SystemChronobiology PhenomenaRNA, MessengerHydrocortisoneFlavoproteinsGene Expression RegulationNeuropeptide YMedian EminencePro-OpiomelanocortinMesocricetusPituitary GlandBody Temperature RegulationArylalkylamine N-AcetyltransferaseReceptors, MelatoninMice, Inbred C57BLHypothalamic HormonesDrug ChronotherapyCorticotropin-Releasing HormoneHeart RateRats, WistarLeptinRod OpsinsProto-Oncogene Proteins c-fosNeurosecretory SystemsPituitary-Adrenal SystemAdrenocorticotropic HormoneFeedback, PhysiologicalSeasonal Affective DisorderTranscription FactorsSleep DeprivationWork Schedule ToleranceNuclear Receptor Subfamily 1, Group F, Member 1OscillometryBasic Helix-Loop-Helix Transcription FactorsInjections, IntraventricularSupraoptic NucleusLight Signal TransductionDrosophila ProteinsOxytocinNuclear ProteinsGonadotropin-Releasing HormoneModels, BiologicalTelemetrySynechococcusPhotoreceptor Cells, InvertebrateGanglionectomySleep, REMOcular Physiological PhenomenaAnalysis of VariancePhodopusBody WeightDyssomniasNeural Pathways