Here Are The Best Sound Types For Falling (And Staying!) Asleep, According To Doctors
Sleep noises are rhythmic ... White noise can also mimic sounds like a humming refrigerator or air conditioner, a hissing ...
Boing Boing on MSN3 个月
Why humming is good for your mental health
The study compares the physiological effects of humming against physical activity, emotional stress, and sleep. The results .