It’s often said that power goes straight to the head.

The pursuit of wealth, status, and ever more power can be as intoxicating as it is addictive.

Ask a toppled tyrant or a scandal-plagued CEO or even a cop-slapping celebrity and — if they’re being honest — they’ll tell you that power is a hell of a drug. And they might have done some things on it that they’re not exactly proud of.

But what about the come-down? While we often see the outward effects of power — the blown-up sense of grandeur, the delusions, the rapacious results, for everyone and everything else — we don’t often look at how power physically rewires the brain.

That is, until modern researchers began to take a sobering, clinical look at the power-addled mind.

Over the course of decades, UC Berkeley psychologist like Dacher Keltner studied powerful people both in the lab and in the field. Power, he concluded, causes brain damage similar to head trauma.

Keltner observed that all the things that may have led someone to acquire power — a keen sense of self-awareness, the ability to connect with people, and even take well-reasoned gambles — wilted under the influence of power.

In short, power disconnected its users from reality.

Young hands holding wrinkled hands Empathy is the key to human interaction, yet it's one of the first things jettisoned by the brain. (Photo: Tyler Olson/Shutterstock)

In an article he wrote for Greater Good magazine, Keltner suggested empathy, a crucial quality for scaling any social hierarchy, was among the first qualities unplugged by power.

“The skills most important to obtaining power and leading effectively are the very skills that deteriorate once we have power,” he wrote.

Another scientist, Sukhvinder Obhi at Canada’s McMaster University, tried to wrap his head around the theory by actually wrapping up powerful people in a cranial-magnetic-stimulation machine. The device was designed to measure motor resonance, or as Obhi notes in a 2013 research paper, the activation of similar brain networks when acting and when watching someone else act.

In other words, it measures the neural processes involved when someone is exhibiting empathy.

Obhi measured it in two groups of people: those with power and those without. He found the first group to be bankrupt.

Power may also make you oblivious

John Stumpf, chairman and CEO of Wells Fargo, Capital Hill 2016 John Stumpf — then chairman and CEO of Wells Fargo — didn't seem smug in his testimony about the unauthorized opening of accounts, but he didn't seem wholly present either. (Photo: Saul Loeb/AFP/Getty Images)

But the ravages of power on the brain may not end there.

As a recent article in The Atlantic suggests, power can be as hard as any street drug on the brain. As an example, writer Jerry Useem looked at the spectacular cognitive crash of former Wells Fargo CEO John Stumpf.

Called before a congressional hearing last fall to answer for epidemic banking irregularities, Stumpf looked nothing like the man who had bulled his way to sip from the chalice of privilege.

In Useem’s words:

“Here was a man who had risen to the top of the world’s most valuable bank, yet he seemed utterly unable to read a room. Although he apologized, he didn’t appear chastened or remorseful. Nor did he seem defiant or smug or even insincere. He looked disoriented, like a jet-lagged space traveler just arrived from Planet Stumpf, where deference to him is a natural law and 5,000 a commendably small number.”

Could power be even harder on a brain the hardest drugs? Could it make Swiss cheese of cerebral functioning and turn longtime users into doddering, forgetful fools?

One thing we know for certain is that, like with any serious substance problem, an addiction to power takes the biggest toll on friends and family.

And it just so happens that powerful people wield influence over the widest swathes of our society.

When someone drowns their empathy in power, we all suffer for it.

So maybe instead of the tough talk on street drugs, policymakers and social influencers might rally against a much more devastating social ill — and tell our children that when it comes to power, just say no. And say yes to empathy.

But then again, as authorities, they too, might be under the influence.