You’ve already heard about the value of a good night’s sleep and the dangers of sleep deprivation to your physical and mental health. If you’re an American, you may well be ignoring those warnings: According to the Centers for Disease Control, 50-70 million Americans suffer from some kind of sleep disorder and several recent studies have found that around a third of us regularly get less than the recommended amount of sleep. High-powered CEOs boast of their ability to function on four hours or less a night and indeed, perhaps they can, but those among us who don’t need much sleep are pretty rare: A solid seven or eight hours a night is what most people need.
From an organizational perspective, as McKinsey highlighted in a report earlier this year, sleep deprivation hurts performance and productivity in a whole host of ways, impairing employees’ ability to solve problems, think critically, learn, help others, and make good decisions. Unsurprisingly, it also has a significant detrimental effect on our leadership abilities. Highlighting his latest research at the Harvard Business Review, management professor Christopher Barnes adds that poor sleep habits can even make leaders less charismatic:
Unfortunately, sleep deprivation undermines both the experience of positive emotion as well as the regulation of emotion. As a result, sleep-deprived leaders are less likely to show positive emotion to their teams, and sleep-deprived team members will be less likely to experience positive emotion. Our hypotheses predicted that sleep deprivation of both leaders and team members can undermine attributions of leader charisma. In other words, sleep-deprived leaders are less inspiring, and sleep-deprived team members are harder to inspire.
My coauthors and I tested these hypotheses with a pair of laboratory experiments. Drawing from the idea of leader communication as a vector for charismatic leadership, in Study 1 (with 88 total participants), we assigned research participants to play the role of a study body leader giving a speech in a commencement ceremony. We gave students time to prepare their speeches, and then recorded them delivering the speech in the laboratory. Half of these students had a normal night of sleep before coming to the study (control condition). We partially sleep deprived the other half, such that they had about two hours less sleep than the participants in the control condition. We then had three evaluators rate the charisma displayed in the speech.
Consistent with our expectations, the sleep-deprived participants were lower in charisma than those in the control condition, and a failure in emotion regulation was a causal factor in the effect. In other words, sleep-deprived leaders are less effective at regulating their displays of positive emotion, and are therefore perceived as less charismatic.