Linked from

The 112 pages that link to Circadian rhythm, each with the reason it gives.

• NocturnalityRelated: It helps synchronize night activity with the daily light–dark cycle.

• HomeostasisRelated: Daily rhythms shift internal processes and the timing of homeostatic demands.

• PhotoperiodismRelated: Circadian timing helps organisms measure the duration of uninterrupted darkness.

• HypothalamusRelated: The suprachiasmatic nucleus coordinates daily rhythms in sleep and bodily functions.

• Bipolar disorderRelated: Sleep and daily rhythms can shift during episodes and are targets of some treatments.

• Light pollutionRelated: Nighttime light can shift or suppress these daily cycles in humans and other organisms.

• Sleep deprivationRelated: Circadian timing can amplify or temporarily mask the effects of lost sleep.

• Endocrine systemRelated: Daily rhythms shape the timing of hormone secretion, including cortisol and melatonin.

• CortisolRelated: Cortisol secretion normally follows a daily pattern, with levels typically highest near waking.

• MelatoninNarrower topic: Melatonin is one output of the circadian system and can also shift its timing.

• SleepRelated: It helps set when sleep propensity rises and falls.

• Polar nightRelated: The absence of sunrise removes a major environmental cue for daily timing.

• InsomniaRelated: Misalignment between sleep timing and the circadian clock can make falling asleep difficult.

• FeverRelated: Normal body temperature varies by time of day, complicating fever thresholds.

• Hypothalamic–pituitary–gonadal axisRelated: Daily timing can modulate reproductive hormone release and fertility-related rhythms.

• Drosophila melanogasterRelated: Mutant flies helped identify genes that generate and regulate biological clocks.

• Animal behaviorRelated: Daily timing helps explain why the same animal behaves differently across the day.

• DeliriumRelated: Disrupted sleep–wake cycles commonly accompany delirium and can worsen its daily fluctuations.

• Periodic functionRelated: Daily biological patterns are modeled as near-periodic functions of time.

• FossorialityRelated: Life underground weakens access to light cues that normally synchronize daily timing.

• FastingRelated: Meal timing during fasting can interact with daily rhythms in metabolism and sleep.

• Seasonal affective disorderRelated: Short winter days can shift biological timing in ways associated with seasonal symptoms.

• Sleep hygieneRelated: Regular schedules and timed light exposure help align sleep with this daily rhythm.

• Gene regulatory networkRelated: Feedback-based gene circuits produce rhythmic expression in many organisms.

• Midnight sunRelated: Persistent summer light can weaken environmental cues that normally synchronize this cycle.

• Suprachiasmatic nucleusNarrower topic: The nucleus coordinates these rhythms across physiological and behavioral processes.

• Cognitive behavioral therapy for insomniaRelated: Consistent wake times help stabilize the timing of sleep.

• Jet lagNarrower topic: Jet lag occurs when this daily timing system remains set to the departure location.

• SunriseRelated: Morning light around sunrise can synchronize biological timing.

• MoonlightRelated: Natural nighttime light can influence biological timing, though moonlight is usually weak.

• Sleep architectureRelated: Circadian timing influences when sleep occurs, while architecture describes its internal stage sequence.

• Sleep homeostasisRelated: Circadian timing can promote wakefulness even when homeostatic pressure is high.

• Adrenal glandRelated: Daily timing shapes the normal pattern of cortisol secretion.

• Daylight saving timeRelated: Shifting civil time can temporarily misalign social schedules with biological timing.

• ManiaRelated: Sleep-wake disruption can accompany mania and may interact with mood regulation.

• Street lightingRelated: Exposure to artificial light at night can affect circadian timing in people and wildlife.

• Body temperatureRelated: Daily rhythms help explain why normal body temperature changes over the course of a day.

• Crepuscular animalRelated: Internal clocks help time activity to recurring dawn and dusk conditions.

• Dark-sky preserveRelated: Reducing nighttime light also limits exposure that can disrupt daily biological timing.

• Home advantageRelated: Time-zone changes can put visiting teams out of sync with local competition schedules.

• Hypothalamic–pituitary–thyroid axisRelated: TSH secretion varies by time of day, complicating interpretation of single measurements.

• Restless legs syndromeRelated: Symptoms commonly intensify in the evening, following a daily rhythm.

• Shift workRelated: Work hours outside daylight can conflict with the body's daily timing system.

• Sleep-wake cycleBroader topic: Its daily timing signal promotes wakefulness or sleep at particular phases.

• ChronotypeNarrower topic: The circadian system provides the daily timing framework in which chronotypes differ.

• CrayfishRelated: Daily rhythms influence when many crayfish emerge to feed or forage.

• Diurnal animalRelated: This internal clock helps align activity with the day–night cycle.

• Limit cycleRelated: Self-sustained cellular clocks can be represented as stable cycles in state space.

• MoodRelated: Daily biological rhythms can influence mood across the day.

• Sleep medicineRelated: Misaligned body-clock timing can produce sleep disorders even when sleep itself is otherwise normal.