From the March 2014 issue of Entrepreneur

Power corrupts, and we know exactly what it corrupts: empathy. The narcissistic mind keen on building fiefdoms has trouble seeing the effect of its actions on others. When at the University of Kent, researcher Ana Guinote found that powerful people tend to ignore peripheral data and don't process information about the less powerful folks around them. Their tunnel vision stays locked on the actions that will win the praise, status or glory they crave. Minions become invisible.

There's evidence that power actually changes the way the brain sees others. A 2013 study by researchers at the University of Toronto and Wilfrid Laurier University in Waterloo, Canada, tracked how the brain's motor resonance system, which mimics the actions of others through what are known as mirror neurons and helps us relate, responded in high-power and low-power individuals. The high-power individuals had less motor simulation, "reduced interpersonal sensitivity" and "decreased processing of social input."

As a result, the powerful have decreased recognition of others' concerns, allowing them to throw their weight around with-out qualm. That gives empire builders the control they need to reduce the fears--insecurity, imperfection, loss of status--that fuel their pursuit of external validation.

But it's more than aversion that motivates empire builders; the brain's motivation and reward systems are also intricately involved. The leading reward mechanism is the neurotransmitter dopamine, a chemical released when we experience pleasurable activities or anticipate something new or novel. Dopamine connects with receptors in the striatum to help commit a person to an action and sets off a reaction that can lead to feelings of satisfaction or accomplishment.

Empire builders get their dopamine hits through activities that pump up ego. It's a never-ending chase for the next external fix--more staffers, bigger budget--all of which is highly ephemeral. The bumps to the striatum and ego fade, since they're based on the gaze of others, and when they do, the fear returns--feelings of worthlessness, inferiority, expendability. Those emotions lead directly to the primitive limbic system of the brain, where fear-quashing goals such as power and status initiate impulsive actions without conscious direction.

Leaders have to find ways to break through the mind lock and the knee-jerk rationales. "The person really believes they're doing the right thing for the right reason," says Annette Simmons, author of Territorial Games. "They have to hear the specific implications that empire-building behavior has on the company and those around them."