The authors start with the astute observation that although much research shows that individual sleep deprivation has consistently negative effects on performance and interpersonal relations, the impact on group performance has hardly been studied.  They point out that some of these negative individual effects -- reduced ability to process information, reduced ability to learn and perform novel tasks, irritability, and impatience -- can disrupt team performance in all sorts of ways. They point out, for example, that some of the worst accidents in history were caused by errors that teams made between 2:00 AM and 4:00 AM, a time when people are especially likely to be sleep deprived,  Examples include the mishaps at Chernobyl and Three-Mile Island. They also report that widespread sleep deprivation was identified as a contributing factor to the errors and poor judgments leading up to the explosion of the Challenger Space Shuttle.

Moreover, if you read accounts of the financial meltdown (I think that Andrew Sorkin's Too Big to Fail is the best), you soon discover that all the major players -- the executives and board members from the troubeled companies and the top government officials like Hank Paulson and Ben Bernake -- were massively sleep deprived as they struggeled to make collective decisions to save individual companies and the financial system. We will never know exactly how many bad decisions were made by these people because they slept so little during the crisis, but a big body of research suggests that any human-being who is subjected to those levels of sleep deprivation will make far worse decisions than they would when well-rested.

The article then goes on to describe various ways in which groups can magnify or dampen the effects of sleep deprived members.  I was especially interested in their argument that when a team has a very hierarchical structure (in other words, is led by a "my way. or the highway" boss), that when the boss is sleep deprived, the rest of the team will have a hard time overcoming his or her errors. Indeed, if you think about some of the effects they describe, if you already have an authoritarian boss, sleep deprivation will make things even worse because he or she will have a harder time processing opposing arguments and be more likely to snap at members who openly disagree.  Another factor they touched on, and I think is worth developing more, is that when people on a team are sleep deprived -- regardless of their personalities -- the resulting irritability and grumpiness is likely (regardless of personality) to cause the kind of nasty interpersonal conflict associated with poor performance and decision-making -- as I have written here before, the best teams have people that fight as if they are right and listen as if they are wrong. Listening as if you are wrong is really tough when you haven't had a good night's sleep in weeks.

Finally, this paper also helped me understand why people in Silicon Valley start-ups are often so grumpy and interpersonally insensitive.  If you wanted to create a recipe for breeding and spreading asshole poisoning, we may have invented the perfect system around here (I live and teach in Silicon Valley) -- take a bunch of people who encourage (and often require) one another to suffer from sleep deprivation for weeks and months on end, force them work very closely together, and then add a big dash performance pressure.  The research cited by Barnes and Hollenbeck, and other research on group effectiveness as well, suggests that this is nearly perfect way to create grumpiness, nastiness, and finger-pointing. It also suggests, most interestingly, that it is also an effective way to dampen creativity.  Plenty of creative work has been done by sleep-deprived teams around here.  But this all makes me wonder, has this happened DESPITE all that fatigue?  As the authors of this intriguing paper suggest, a lot more research is needed on sleep deprivation and team performance, but it is fascinating topic.