We’ve all been there. Some mornings — and afternoons, and evenings — there’s simply no way to deal with people. Especially if the night before was far from being a dream.
But why is it that sleeping badly makes us so inclined to be grumpy and uncooperative? Experts reckon it all comes down to a part of the brain that’s been with us since the days when we were watching out for sabre-toothed tigers rather than squaring off with Sarah in accounts.
The part of our brain that deals with our primal, instinctive emotions — the bit some people call our ‘chimp brain’ — is called the limbic system. In it are two small oval areas that get their name from the Greek for almond, because of their shape. Together, they’re known as the amygdala.
The amygdala is the bit that reacts emotionally to generate a fight, flight or freeze response when we’re threatened. The problem is, it has no way of knowing if it's dealing with a real, life-threatening problem or a minor irritation. And when it’s on high alert — such as when you haven’t slept properly — it’s primed to make a mountain out of any number of molehills.
One study involving Matthew Walker found that after just one night of disturbed sleep, people who were exposed to negative imagery had an amygdala that lit up on a brain scan. In fact, the amygdala was up to 60% more active in their brains, than in the brains of people who got a full night’s sleep. Sleep better, and you let your pre-frontal cortex (the rational bit) take the wheel and sort the drama from the crisis.
Now you know why we keep telling you you should #TryFor8 hours in bed every night.
One way to find out whether you might be giving your amygdala something to shout about is to track your sleep. You can then match up better and worse nights to the way you feel and respond to others the next day. Which in turn might inspire you to make more sleep-friendly choices during your days. Luckily, you can track your sleep for free (and without even needing a wearable) with the Simba Sleep App. And we’ve packed in some expert coaching from rugby legend Jamie Roberts and award-winning journo Peta Bee, just in case that wasn’t enough.
So whenever you’re ready, you can start waking up on the right side of the bed more often.