Lack of sleep might be doing more than just making you groggy — it could be sabotaging your brain’s ability to keep intrusive thoughts at bay.
A new study published in the Proceedings of the National Academy of Sciences found that sleep deprivation weakens the brain’s defense against unwanted memories, allowing them to flood your mind.
Sleep deprivation’s hidden toll
We’ve long known poor sleep is a major player in emotional regulation, but until now, scientists weren’t sure why.
Researchers at the University of York and the University of East Anglia tested 85 healthy adults to get to the bottom of it. Half got a full night’s rest, while the other half pulled an all-nighter.
Using cutting-edge technology, the team monitored brain activity as participants were shown faces paired with emotionally charged images, such as car crashes or fights. Then, they were asked to either recall or suppress the scenes tied to each face.
The results were striking: The well-rested group showed far more activity in the right dorsolateral prefrontal cortex (the brain’s command center for thoughts, actions and emotions) when suppressing negative memories.
The sleep-deprived group, meanwhile, struggled to keep their intrusive thoughts in check, showing less activity in the critical brain region.
Notably, the rested participants also displayed reduced activity in the hippocampus — the part of the brain responsible for memory retrieval — indicating they could “shut down” unwanted memories more effectively than their sleep-deprived counterparts.
Understanding the missing link
With one-third of US adults struggling with sleep issues and 26% facing diagnosable mental health conditions every year, the new research could shift how we approach such problems.
“Given that memories play a central role in our affective perception of the external world, memory control failures may go a long way towards explaining the relationship between sleep loss and emotional dysregulation,” said Marcus Harrington, lead author of the study and a psychology lecturer at UEA.
Experts are hopeful that understanding how sleep impacts memory control could lead to breakthroughs in treatments for anxiety, depression, post-traumatic stress disorder and other mental health conditions.
“[Now] we can perhaps work on more targeted treatments and behavioral therapies that help with improving sleep and as a result support the brain in doing what it has so cleverly adapted to doing, allowing us to lead mentally fit lives,” said Scott Cairney, co-author of the study and a senior lecturer in psychology at the University of York.
Sleep tips
Not getting enough shut-eye? Here are some science-backed tips from experts to help you sleep like a baby.
- Stick to a sleep schedule: Try going to bed and waking up at the same time every day, even on weekends. This helps regulate your body’s internal clock.
- Establish a relaxing bedtime routine: Ditch the bright lights and screens at least an hour before sleep. Instead, try reading a book, taking a warm bath or listening to calming music.
- Focus on your breath: Deep breathing exercises can help reduce stress, activate your parasympathetic nervous system, which calms the body, and stimulate the production of melatonin, an essential sleep hormone.
- Try some sleep hacks: If you’re still tossing and turning, you could try techniques like the “alpha bridge method,” the “house tour sleep hack,” or “cognitive shuffling.” These quirky tricks have shown promise for many people in helping them fall asleep.
If you’re still awake after 20 minutes, experts recommend getting out of bed and doing something relaxing in another room — reading or gentle stretching, for example. This prevents your bed from becoming a stress zone.
Once you’re feeling drowsy, hit the pillow and give these tips another try.
