What makes some men sexual harassers?

about the world around you,” Mr. Keltner said. “Someone like Harvey Weinstein may think ‘I’m so horny right now, so the whole world must feel that way.’ “

What makes these men think women want to see all that?

One of the most puzzling and icky details from the recent string of high-profile cases is this signature move of several powerful men: Exposing themselves to women, apparently with the expectation that those women are attracted to them or will be once they see their bodies.

There is, surprisingly, a scientific explanation for this. A particularly eyeopening 2011 study found that people in leadership often pick up phantom sexual signals from subordinates that aren’t really there.

The experiment designed by Jonathan Kunstman and Jon Maner took 78 adults and paired them with a member of the opposite sex. Those pairs were assigned a Lego-building project, with one person put in charge of the other. In private interviews at the end of the project, those who were appointed leaders were much more likely to have perceived sexual interest from their subordinates, even when the subordinates said in surveys that they had no sexual interest at all.

When researchers studied video of most pairs interacting, they found the leaders much more likely to act on that misperception, touching the subordinate’s leg or engagingin eye gazing.

“Power creates this perfect mental storm for misconduct,” said Mr. Kunstman, an experimental social psychologist at Miami University of Ohio. “This tendency to overperceive romantic interest can lead to a feeling of freedom to touch, which can then lead to misconduct.”

So what are these men really after? Sex or dominance?

“The hackneyed phrase everyone always says about sexual harassment is that it’s not really about sex, it’s about power,” said Illinois researcher Pryor. “But that’s not really true. It’s about both.”

In recent years, psychologists trying to understand the relationship between power and sex have found that, for many men who score high on the harassment scale, the two ideas are often intertwined.

“They are two sides of the same coin and so strongly fused that it’s impossible to cleave them apart,” Mr. Pryor said. “If these men have power over someone, they find it difficult not to have those sexual ideas come to mind. And more they think about it, the more that association is reinforced.”

Why is it almost always men doing the harassing?

There’s a statistical answer for this: The way our society stands now, with all its flaws, discriminatory biases, and historical and cultural baggage, there remain many more men in leadership positions than women. (At least one woman in a position of power, however, has recently been accused of harassing a malesubordinate.)

There’s also a feminist structural reading of such harassment: Harassment often serves as a vehicle to exert dominance and put women in their place.

But behavioral science has also shown there are behavioral differences between the sexes, said Louise Fitzgerald, a psychologist at University of Illinois at Urbana Champaign.

“It’s not like women are somehow immune from dark personality traits,” she said, “but we know from gender research that men are more aggressive, more socialized to seek sex and believe they have a right to it.”

How likely is the #MeToo movement to change anything?

Ms. Fitzgerald, who has spent three decades studying the devastating effects of sexual harassment, is surprisingly pessimistic about the current movement producing momentous change.

“I remember thinking the same thing during the Clarence Thomas hearings, that the cultural moment had come and everything would change,” she said. “But here we are 20-some years later when people are suddenly rediscovering yet again that sexual harassment exists.”

The cases now making headlines, she noted, largely involve high-profile folks in Hollywood and media. “Will that have an effect on the woman being harassed at her job at Walmart or on the factory floor? I don’t know.”

But one thing the #MeToo movement may be changing is the stigma of sexual assault and harassment, said Mr. Pryor, the longtime harassment researcher. “The #MeToo movement shows just how common these experiences are. And that may take away the silence that often allows the harassment to be hidden.”

Another important byproduct of the #MeToo movement may be increased interest in sexual harassment research, say Mr. Pryor, Ms. Fitzgerald and others.

When Mr. Pryor began studying sexual harassment in the 1980s, there was little support for the work. Mr. Pryor funded many of his earliest studies himself and had to work in his spare time to develop research like his “Likelihood to Sexually Harass” scale. In the decades since, the situation has improved but only marginally, said Mr. Pryor, now semi-retired.

“With everything we’re seeing now, that will hopefully change — maybe too late to make a difference in my career — but for others this could be a turning point,” he said.