Why Can’t We Fall Asleep?

Why Can’t We Fall Asleep?

By Maria Konnikova

Here’s what’s supposed(səˈpōzd,səˈpōzid) to happen when you fall asleep. Your body temperature(-ˌCHo͝or,ˈtemp(ə)rəCHər) falls, even as your feet and hands warm up—the temperature changes likely help the circadian(sərˈkādēən) clocks throughout your body to synchronize(ˈsiNGkrəˌnīz). Melatonin(ˌmeləˈtōnin) courses(kôrs) through your system—that tells your brain it’s time to quiet(ˈkwīət) down. Your blood(bləd) pressure(ˈpreSHər) falls and your heart(härt) rate slows. Your breathing(ˈbrēT͟HiNG) evens out. You drift off to sleep.

That, at least, is the ideal(īˈdē(ə)l). But going to sleep isn’t always a simple process(prəˈses,ˈpräsəs,ˈpräˌses,ˈprō-), and it seems to have grown more problematic(ˌpräbləˈmatik) in recent years, as I learned through a series(ˈsi(ə)rēz) of conversations this May, when some of the world’s leading(lēd) sleep experts(ˈekˌspərt) met with me to share their ongoing research into the nature(ˈnāCHər) of sleeping. (The meetings were facilitated(fəˈsiliˌtāt) by a Harvard Medical(ˈmedikəl) School Media(ˈmēdēə) Fellowship(ˈfelōˌSHip).) According to Charles(CHärlz) Czeisler, the chief(CHēf) of the Division(diˈviZHən) of Sleep and Circadian Disorders at Brigham and Women’s Hospital, over the past five decades(ˈdekād) our average(ˈav(ə)rij) sleep duration on work nights has decreased by an hour and a half, down from eight and a half to just under seven. Thirty-one per cent(sent) of us sleep fewer than six hours a night, and sixty-nine per cent report insufficient(ˈinsəˈfiSHənt) sleep. When Lisa Matricciani, a sleep researcher at the University of South Australia(ôˈstrālyə,əˈstrāl-), looked at available sleep data for children from 1905 to 2008, she found that they’d lost nearly a minute of sleep a year. It’s not just a trend(trend) for the adult(əˈdəlt,ˈadˌəlt) world. We are, as a population, sleeping less now than we ever have.

The problem, on the whole(hōl), isn’t that we’re waking up earlier. Much of the change has to do with when we choose to go to bed—and with how we decide to do so. Elizabeth(iˈlizəbəTH) Klerman is the head of the Analytic(ˌanlˈitik) and Modeling(ˈmädl-iNG) Unit(ˈyo͞onit), also in the Sleep and Circadian Disorders division(diˈviZHən) at Brigham and Women’s Hospital. Her research tracks how multiple(ˈməltəpəl) individual(ˌindəˈvijəwəl) differences in our environment affect our circadian rhythms(ˈriT͟Həm) and our ability to fall asleep easily and soundly. “When you go to bed affects how long you can sleep, no matter how tired you are,” she told me.

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