Contributed by Tara Swart, MIT Sloan Senior Lecturer, neuroscientist, and executive leadership coach.
What makes a good leader?
Senior executives, managers, and business leaders are paid to use their brains. So it is surprising how little emphasis many put on this vital organ.
In a fast-paced world that is constantly changing, the brain's executive functions, such as creative and flexible thinking, task-switching, bias suppression, and emotional regulation, are becoming increasingly important. But our ability to perform well at these outputs will be enhanced only if fed the right inputs. These include nourishing, hydrating, and oxygenating the brain appropriately, simplifying tasks to give the brain mindful time, and resting it.
That final element—rest—is one of the most crucial. We often hear stories about famous leaders such as Margaret Thatcher surviving and even thriving on very little sleep (Thatcher did suffer from dementia in her later life). It is true that an extremely limited number of people (1-2% of the population) have a genetic mutation that reduces the amount of sleep they truly require for optimal functioning to 4-5 hours a night. But for the rest of us, getting seven to nine hours of good, quality sleep every night is vital for staying on top of our game.
Why is sleep important?
Sleep deprivation will negatively impact your cognitive performance. Getting less sleep than the recommended amount can cause an apparent IQ loss of five to eight points the next day, and population norm studies have shown that losing an entire night’s sleep can lead to up to one standard deviation loss on your IQ. In other words, you're effectively operating with the equivalent of a learning disability.
Shorting your sleep can have longer-term effects as well. Our glymphatic system requires 7-8 hours to clean our brains, a process which flushes out protein plaques and beta amyloid tangles that can lead to dementing diseases if allowed to accumulate. Not getting enough sleep, or getting poor quality sleep (which includes sleeping after drinking alcohol) inhibits this process and can therefore increase the risk of developing these types of disease.