When does a mouse not sleep? - briefly
A mouse stays awake during its nocturnal activity period and whenever it senses danger or is busy feeding. It only sleeps during safe, stable rest intervals.
When does a mouse not sleep? - in detail
Mice are nocturnal mammals; they normally spend the majority of daylight hours sleeping and become active during the night. Their sleep–wake cycle is regulated by an internal circadian clock that aligns physiological processes with the light–dark environment.
Awake periods increase when external or internal factors disrupt the normal rhythm. Common situations that prevent rest include:
- Exposure to bright light during the dark phase, which suppresses melatonin release.
- Presence of predators or sudden noises, triggering a heightened stress response.
- Extreme ambient temperatures, either cold or heat, that demand thermoregulatory effort.
- Acute illness or infection, which raises body temperature and metabolic demand.
- Developmental stages such as early post‑natal life, when pups spend most of the time nursing and are rarely still.
- Experimental manipulations that involve forced activity, pharmacological stimulants, or genetic alterations affecting sleep‑regulating pathways.
- Deprivation of food or water, leading to foraging behavior that overrides rest.
Physiological markers confirm wakefulness in these contexts: elevated corticosterone levels, increased heart rate, and sustained cortical EEG activity characteristic of wake states. Once the disruptive stimulus is removed, the circadian system typically re‑establishes the usual sleep pattern, though prolonged disturbances can cause chronic sleep fragmentation.