Details for Ears Work All Night Long
Even when your sleep, your ears continue to function and process sound. But there is a significant difference in how your brain responds to the noise, depending on which stage of sleep you’re in. At certain points of deep sleep, your brain appears to tune out the external world so that normal noises don’t disrupt sleep (loud noises can jar your awake). When you’re in lighter stages of sleep, the brain responds to normal levels of noise, which could explain why even slight sounds wake you up.