Ever wondered why a tired person is more likely to be aggressive and difficult to deal with? Scientists have been studying the impact of sleep on our ability to recognise facial expressions and read social situations, and the results can help us understand more than ever the importance of sleep when interacting with others.
Malcolm Gladwell in his seminal book ‘Blink’ discusses the importance of how we ‘figure out what someone else is thinking’, referring predominantly to the various recognisable facial expressions we use in everyday life. Remarkably, regardless of nationality or culture, wherever researchers looked, people agreed on what these expressions meant.
So how does sleep link in to this?
To begin with, we have to understand that there are six widely agreed basic emotional categories:
Some of these basic emotions are felt to be more primitive and ‘hard-wired’ as they have always directly affected our chance of survival, such as anger (am I about to be attacked?), fear (what is everyone scared of?) and disgust (was that food bad?). Others, like happiness and sadness, are more ‘modern’ and have evolved to let us navigate highly complex social interactions that involve empathy.
Imagine a pack of cards with photographs of faces showing the complete range of these emotions. This pack contains not just the basic six, but also complex combinations formed by morphing pairs of emotions, (e.g. 70% fear and 30% surprise).
Work using these ‘cards’ by William Killgore has shown we are good at recognising the basic six, even when sleep deprived. But when the task is a bit more complex, with the mixture of emotions shown in the images, sleep loss takes a big toll. People performed well at the ‘threat/survival’ facial images, but lost the ability to recognise the ‘less urgent’ social and emotional images involving happiness and sadness.
Whilst not appearing disastrous at first, this all starts to become worrying in combination with other related work, showing that sleep deprived people are more likely to break their own moral beliefs, report lower levels of empathy and feel anxious or suspicious of others.
Aside from its effect on recognising facial emotions, sleep deprivation also has a profound impact on our ability to make rational decisions. When we have been awake for 16-18 hours, our reaction times are similar to when our blood alcohol levels are at the legal drink/drive limit, meaning we are not in a sound frame of mind to make important decisions.
In any job, the ability to interact with others and make good decisions are crucial to achieving success. Arguably one of the clearest examples of this importance, is in the field of politics. So why do so many politicians suffer from sleep deprivation?
Margaret Thatcher remains one of the famous ‘sleepless elite’, waking after just four hours sleep to listen to Radio 4 each morning. Barack Obama, hopefully more rested now than when he held the reins, discussed holding conferences at 11pm, receiving crucial emails at 1am and sleeping just 5 hours a night during his presidency.
Alarmingly, sleep still appears to remain expendable for modern politicians. Both Donald Trump and Theresa May claim to only sleep a few hours each night, often working well into the early hours, leaving them sleep deprived and potentially on edge in key negotiations that involve complex emotional interactions and making key decisions.
As one of the most worrying traits of sleep deprivation is losing the ability to recognise when it is affecting you, we can safely assume that many politicians throughout history will have unknowingly found themselves in a situation where their better judgement has been impaired due to a lack of sleep, and were unable to recognise the cause of the issue.
So whether you are a high profile politician, or simply have to deal with others on a daily basis, preventing sleep deprivation could be the key to getting the best out of your day and perform to the best of your abilities.
Perhaps the world would sleep a bit more peacefully if our world leaders valued sleep a little more!