The Science of Moods
A growing body of research on the human brain proves that, for better or worse, leaders’ moods affect the emotions of the people around them. The reason for that lies in what scientists call the open-loop nature of the brain’s limbic system, our emotional center. A closed-loop system is self-regulating, whereas an open-loop system depends on external sources to manage itself. In other words, we rely on connections with other people to determine our moods. The open-loop limbic system was a winning design in evolution because it let people come to one another’s emotional rescue—enabling a mother, for example, to soothe her crying infant.
The open-loop design serves the same purpose today as it did thousands of years ago. Research in intensive care units has shown, for example, that the comforting presence of another person not only lowers the patient’s blood pressure but also slows the secretion of fatty acids that block arteries. Another study found that three or more incidents of intense stress within a year (for example, serious financial trouble, being fired, or a divorce) triples the death rate in socially isolated middle-aged men, but it has no impact on the death rate of men with many close relationships.