Tossing and turning at night? You’re not alone. U of T Mississauga anthropologist and sleep expert David Samson explains why we experience insomnia, how sleep helps boost physical and emotional health, and offers tips for a better night’s rest in uncertain times.
Samson studies the link between human evolution and sleep, with a particular focus on cognition. He is a co-author on a new study that investigates the evolutionary link between fear and insomnia.
According to Samson, early humans developed sense of fear as protection from predators in ancestral environments like the African Savannah. “A healthy dose of fear and sleep architecture, where certain members of the group are awake at any given time, served the function of keeping us alive,” he says.
“However, we evolved fear for acute, not chronic responses,” Samson continues. Acute fear subsides when no attack arrives but in a contemporary setting, modern humans have a “misguided sense of fear.” Our busy nighttime brains confuse an upcoming work presentation or a spate of bad news with a lion attack.
“When fear fails to subside, for some people it becomes chronic and leads to insomnia.”
That fear may be exacerbated during the COVID-19 pandemic. During social isolation, many of us are in close quarters with household members, and physically isolated from supportive friends and family. Coupled with never-ending news updates, Samson says the situation can “create a baseline state of chronic fear with nowhere to direct it,” resulting in long nights tossing and turning.
“In this situation, sleep becomes more important than ever,” he says.
Research shows that sleep is critical to supporting our physical and emotional health. On the emotional front, sleep helps us to process emotions and supports emotional regulation during stressful situations.
Sleep is also critical to keeping us physically healthy. “In deep sleep, you’re developing antibodies that help fight off infection,” Samson says. “Sleep helps with immune regulation, and that’s really important.”
While so much feels beyond our control, Samson says sticking to a pre-bedtime routine can help you to get some healthy shut-eye:
Cut the Snacks
Natural circadian rhythms send a cue your body that it’s time to wind down for sleep, but eating sends a conflicting signal that it’s time to be awake. Scheduling dinner three hours before bedtime and cutting after-dinner snacks is “a powerful strategy” in a good sleep routine, he says.
Playing competitive video games increases the body’s uptake of hormones that drive the desire to win, which makes it hard to get to sleep once the game is over. “Gamers are the worst-sleeping cohort," says Samson, who is also a dedicated gamer. He suggests keeping gaming sessions to daytime only.
Samson advises limiting blue light from screens and light fixtures wherever possible. That means turning off unnecessary lights around the house in the evening. Using warm hued light bulbs or blue light-blocking glasses will help, too.
“As we are stuck indoors, many of us are connecting online for social interaction, entertainment and news,” Samson says. He recommends powering down screens and other sources of blue light at least an hour before bedtime, and ensuring our bedrooms are free of distractions. Reading a book is a great way to unwind before drifting off.
Tips for parents
Parents can help kids rest easy by creating a reliable bedtime routine and modelling good behaviour themselves. According to Samson, a establishing a solid routine in childhood will be beneficial in the long-term, too. “Getting kids to practice now will add thousands of good-quality sleep hours to their adult lives.”
Samson’s research is supported by a Social Sciences and Humanities Research Council Insight Development Grant and U of T’s Connaught New Researcher Award. His latest research, “Failure of fear extinction in insomnia: an evolutionary perspective” is published in Sleep Medicine Reviews.