In order to fall asleep at night, I must run a gantlet of bedtime rituals. I must be marinating in overnight-skin-care products from head to toe. One (but only one) of my legs must be hooked around the side of my covers, poised to alert me to the presence of monsters. I must be lying on my stomach, with one arm folded under my head between me and my pillow. Not only must the air in the room be frigid, but it must be blowing directly on me.
Most people will probably cop to at least one idiosyncratic sleep habit. The presence of a fan is a common one. Some people are so attached to a particular pillow that they’ll haul it through the airport. Others are dead set on having their toes dangle off the mattress. Some adults still cuddle a stuffed animal. I started taking this inventory of bedtime peculiarities after someone asked whether I could explain why her face always had to be touching her childhood blanket at night.
Requiring a particular toe positioning or pillow assortment can sound silly, but if you’re convinced you need these rituals, then their absence can affect your ability to fall asleep, disturb someone you sleep with, harm your job performance, and mess with your life. Clinical sleep disorders such as insomnia or apnea affect as many as 70 million Americans, and 60 percent of the country’s adults report experiencing sleep problems every or most nights. Bedtime eccentricities might not have an obvious connection to such widespread difficulties, but they can play a quietly pivotal role. For most people, how they came to develop the entries on their own nighttime checklist is entirely opaque, as is why completing them feels so essential.