In the past five years, research in the emerging field of social neuroscience–the study of what happens in the brain while people interact–is beginning to reveal subtle new truths about what makes a good leader.

The salient discovery is that certain things leaders do–specifically, exhibit empathy and become attuned to others’ moods–literally affects both their own brain chemistry and that of their followers. Indeed, researchers have found that the leader-follower dynamic is not a case of two (or more) independent brains reacting consciously or unconsciously to each other. Rather, the individual minds become, in a sense, fused into a single system.

Followers Mirror Their Leaders-Literally
Perhaps the most stunning recent discovery in behavioral neuroscience is the identification of “mirror neurons” in widely dispersed areas of the brain. It turns out that there’s a subset of mirror neurons whose only job is to detect other people’s smiles and laughter, prompting smiles and laughter in return. A boss who is self-controlled and humorless will rarely engage those neurons in his team members, but a boss who laughs and sets an easygoing tone puts those neurons to work, triggering spontaneous laughter and knitting his team together in the process. A bonded group is one that performs well, as our colleague Fabio Sala has shown in his research. He found that top-performing leaders elicited laughter from their subordinates three times as often, on average, as did midperforming leaders. Being in a good mood, other research finds, helps people take in information effectively and respond nimbly and creatively. In other words, laughter is serious business.

It certainly made a difference at one university- based hospital in Boston. Two doctors we’ll call Dr. Burke and Dr. Humboldt were in contention for the post of CEO of the corporation that ran this hospital and others. Both of them headed departments, were superb physicians, and had published many widely cited research articles in prestigious medical journals. But the two had very different personalities. Burke was intense, task-focused, and impersonal. He was a relentless perfectionist with a combative tone that kept his staff continually on edge. Humboldt was no less demanding, but he was very approachable, even playful, in relating to staff, colleagues, and patients. Observers noted that people smiled and teased one another–and even spoke their minds–more in Humboldt’s department than in Burke’s. Prized talent often ended up leaving Burke’s department; in contrast, outstanding folks gravitated to Humboldt’s warmer working climate. Recognizing Humboldt’s socially intelligent leadership style, the hospital corporation’s board picked him as the new CEO.

The "Finely Attuned" Leader
Great executives often talk about leading from the gut. Indeed, having good instincts is widely recognized as an advantage for a leader in any context, whether in reading the mood of one’s organization or in conducting a delicate negotiation with the competition. Intuition, too, is in the brain, produced in part by a class of neurons called spindle cells because of their shape. These cells help us gauge whether someone is trustworthy and right (or wrong) for a job. Within one-twentieth of a second, our spindle cells fire with information about how we feel about that person; such “thinslice” judgments can be very accurate, as follow-up metrics reveal. Therefore, leaders should not fear to act on those judgments, provided that they are also attuned to others’ moods.

Such attunement is literally physical. Followers of an effective leader experience rapport with him or her–what we and our colleague Annie McKee call “resonance.” Much of this feeling arises unconsciously, thanks to mirror neurons and spindle-cell circuitry. But another class of neurons is also involved:

Oscillators coordinate people physically by regulating how and when their bodies move together. You can see oscillators in action when you watch people about to kiss; their movements look like a dance, one body responding to the other seamlessly. The same dynamic occurs when two cellists play together. Not only do they hit their notes in unison; thanks to oscillators, the musicians’ right brain hemispheres are more closely coordinated.

Firing Up Your Social Neurons  
The firing of social neurons is evident all around us. We once analyzed a video of Herb Kelleher, a cofounder and former CEO of Southwest Airlines, strolling down the corridors of Love Field in Dallas, the airline’s hub. We could practically see him activate the mirror neurons, oscillators, and other social circuitry in each person he encountered. He offered beaming smiles, shook hands with customers as he told them how much he appreciated their business, hugged employees as he thanked them for their good work. And he got back exactly what he gave. Typical was the flight attendant whose face lit up when she unexpectedly encountered her boss. “Oh, my honey!” she blurted, brimming with warmth, and gave him a big hug. She later explained, “Everyone just feels like family with him.”

Unfortunately, it’s not easy to turn yourself into a Herb Kelleher or a Dr. Humboldt if you’re not one already. We know of no clear-cut methods to strengthen mirror neurons, spindle cells, and oscillators; they activate by the thousands-per-second during any encounter, and their precise firing patterns remain elusive. What’s more, intelligence can often backfire. When you make an intentional effort to coordinate movements with another person, it is not only oscillators that fire. In such situations the brain uses other, less adept circuitry to initiate and guide movements; as a result, the interaction feels forced. The only way to develop your social circuitry effectively is to undertake the hard work of changing your behavior (see “Primal Leadership: The Hidden Driver of Great Performance,” by Annie McKee in the December 2001 issue of the Harvard Business Review).

How to Become Scoially Smarter
To see what social intelligence training involves, consider the case of a top executive we’ll call Janice. She had been hired as a marketing manager by a Fortune 500 company because of her business expertise, outstanding track record as a strategic thinker and planner, reputation as a straight talker, and ability to anticipate business issues that were crucial for meeting goals. Within her first six months on the job, however, Janice was floundering; other executives saw her as aggressive and opinionated, lacking in political astuteness, and careless about what she said and to whom, especially higher-ups.

To save this promising leader, Janice’s boss called in Kathleen Cavallo, an organizational psychologist and senior consultant with the Hay Group, who immediately put Janice through a 360-degree evaluation. Her direct reports, peers, and managers gave Janice low ratings on empathy, service orientation, adaptability, and managing conflicts.

When Cavallo presented performance feedback as a wake-up call to Janice, she was of course shaken to discover that her job might be in danger. What upset her more, though, was the realization that she was not having her desired impact on other people. Cavallo initiated coaching sessions in which Janice would describe notable successes and failures from her day. The more time Janice spent reviewing these incidents, the better she became at recognizing the difference between expressing an idea with conviction and acting like a pit bull. She began to anticipate how people might react to her in a meeting or during a negative performance review; she rehearsed more-astute ways to present her opinions; and she developed a personal vision for change. Such mental preparation activates the social circuitry of the brain, strengthening the neural connections you need to act effectively; that’s why Olympic athletes put hundreds of hours into mental review of their moves.

At one point, Cavallo asked Janice to name a leader in her organization who had excellent social intelligence skills. Janice identified a veteran senior manager who was masterly both in the art of the critique and at expressing disagreement in meetings without damaging relationships. She asked him to help coach her, and she switched to a job where she could work with him–a post she held for two years. Janice was lucky to find a mentor who believed that part of a leader’s job is to develop human capital. Many bosses would rather manage around a problem employee than help her get better. Janice’s new boss took her on because he recognized her other strengths as invaluable, and his gut told him that Janice could improve with guidance.

Before meetings, Janice’s mentor coached her on how to express her viewpoint about contentious issues and how to talk to higher-ups, and he modeled for her the art of performance feedback. By observing him day in and day out, Janice learned to affirm people even as she challenged their positions or critiqued their performance. Spending time with a living, breathing model of effective behavior provides the perfect stimulation for our mirror neurons, which allow us to directly experience, internalize, and ultimately emulate what we observe.

Janice’s transformation was genuine and comprehensive. In a sense, she went in one person and came out another. If you think about it, that’s an important lesson from neuroscience: Because our behavior creates and develops neural networks, we are not necessarily prisoners of our genes and our early childhood experiences. Leaders can change if, like Janice, they are ready to put in the effort. As she progressed in her training, the social behaviors she was learning became more like second nature to her. In scientific terms, Janice was strengthening her social circuits through practice. And as others responded to her, their brains connected with hers more profoundly and effectively, thereby reinsocial forcing Janice’s circuits in a virtuous circle. The upshot: Janice went from being on the verge of dismissal to getting promoted to a position two levels up.

Hard Metrics of Social Intelligence
Our research over the past decade has confirmed that there is a large performance gap between socially intelligent and socially unintelligent leaders. At a major national bank, for example, we found that levels of an executive’s social intelligence competencies predicted yearly performance appraisals more powerfully than did the emotional intelligence competencies of self-awareness and self-management.

Social intelligence turns out to be especially important in crisis situations. Consider the experience of workers at a large Canadian provincial health care system that had gone through drastic cutbacks and a reorganization. Internal surveys revealed that the frontline workers had become frustrated that they were no longer able to give their patients a high level of care. Notably, workers whose leaders scored low in social intelligence reported unmet patient-care needs at three times the rate–and emotional exhaustion at four times the rate–of their colleagues who had supportive leaders. At the same time, nurses with socially intelligent bosses reported good emotional health and an enhanced ability to care for their patients, even during the stress of layoffs. These results should be compulsory reading for the boards of companies in crisis. Such boards typically favor expertise over social intelligence when selecting someone to guide the institution through tough times. A crisis manager needs both.

As we explore the discoveries of neuroscience, we are struck by how closely the best psychological theories of development map to the newly charted hardwiring of the brain. Back in the 1950s, for example, British pediatrician and psychoanalyst D.W. Winnicott was advocating for play as a way to accelerate children’s learning. Similarly, British physician and psychoanalyst John Bowlby emphasized the importance of providing a secure base from which people can strive toward goals, take risks without unwarranted fear, and freely explore new possibilities. Hardbitten executives may consider it absurdly indulgent and financially untenable to concern themselves with such theories in a world where bottom-line performance is the yardstick of success. But as new ways of scientifically measuring human development start to bear out these theories and link them directly with performance, the so-called soft side of business begins to look not so soft after all.

Excerpted with permission from The Harvard Business Review. © 2008 Harvard Business School Publishing.
Daniel Goleman is a co-chairman of the Consortium for Research on Emotional Intelligence in Organizations at Rutgers University. He is the author of “Social Intelligence: The New Science of Human Relationships” (Bantam, 2006).
Richard Boyatzis is the H.R. Horvitz Chair of Family Business and a professor in the departments of organizational behavior, psychology, and cognitive science at Case Western Reserve University in Cleveland. He is a co-author, with Annie McKee and Frances Johnston, of “Becoming a Resonant Leader” (Harvard Business Press, 2008).