They should not be surprised. For decades, research has shown that lack of sleep leads to extremely poor thinking. It is cited as a culprit in most industrial accidents - and for just the same reasons that it may lead to unethical behavior: people who haven't slept well for a long time are more rigid in their thinking, have greater difficulty responding to changing circumstances and take longer to reason correctly. They demonstrate what the Chemical Safety Board calls 'cognitive fixation' or tunnel vision: they are so focused on task that they can't think beyond it to the implications of their actions.
There are clear physiological reasons for this. After twenty-four hours of sleep deprivation, there is an overall reduction of 6 per cent in glucose reaching the brain. That's one reason why we start to crave comfort food - doughnuts, sweets - when we're tired: our brains crave sugar. Moreover, the loss isn't shared equally. The areas of your brain responsible for processing and critical thinking lose 12 - 14 percent of their glucose - and those are the areas of the brain most needed for thinking: for distinguishing between ideas, for social control and to be able to tell the difference between good and bad. Meanwhile, the thalamus, whose job it is to keep you awake - works extra hard. So, as Harvard psychologist Daniel Gilbert puts it, "resource depletion specifically disable cognitive elaboration. Not only does doubt seem to be the last to emerge, but it also seems to be the first to disappear."
From the perspective of evolutionary biology, this makes sense: if you're walking through the jungle and are pounced on by a tiger, it is far more important to stay awake than to be able to identify what kind of tiger you're confronting.
The New Mad Men?
But in today's workplace, critical thinking and discrimination are fundamental to what most of us do. We need to be able to think through the consequences of our actions. But that's just the capacity we lose first when we get tired.
"We now know," says Charles Czeisler, Professor of Sleep Medicine at Harvard Medical School, "that twenty-four hours without sleep, or a week of sleeping four or five hours a night induces an impairment equivalent to a blood alcohol level of 0.1 per cent. [This is over the legal limit for driving.] We would never say "This person is a great worker! He's drunk all the time!" Yet we continue to celebrate people who sacrifice sleep."
This has serious repercussions for the way that we manage people. Most corporations celebrate the heroes prepared to pull all-nighters, jump on the red eye or accept an extra shift. We are still stuck in an Industrial Revolution mindset, according to which more hours = more productivity, even though we've known for 100 years that that isn't true. In industrial accidents, the impact of sleep loss is easy to trace - but whenever you examine highly unethical work cultures, you inevitably uncover an ethos that celebrates long hours. The fact that most mergers and acquisitions are completed after a few all-nighters may explain why those deals mostly fail.
But maybe we're all too tired to understand what is, after all, a simple message: there are hard limits to what our minds can and will do. Our willful blindness to the data is written all over unethical, wasteful and dangerous workplaces.