The conversation about diversity in Hollywood often centers on fairness. It’s unfair that just over a quarter of speaking roles went to people of color in 2015’s top movies ― that Asians and Latinx nabbed tiny slivers. It’s unfair that women made up less than one-third of protagonists in top movies in 2016. It’s unfair that black, Asian and Latinx actors were completely left out of acting categories in the Academy Awards last year, and the year before that.

It is unfair. Although the Academy announced a small list of Oscar nominees featuring more black actors in 2017, for years, researchers have counted and recounted the vast population of bodies making up content in TV and film, only to find, again and again, that the industry’s struggle to represent people of color, women and other groups the way we see them in real life ― as people with likes and dislikes, habits and whims, hopes and fears ― is endemic.

But it’s not just unfair. Even if we don’t stop to think much about the summer blockbuster we watch to sit in a cool theater on a hot day, or the show we turn on while we’re making dinner, entertainment media saturates our lives. And for decades, researchers have worried over the effect those stories have on viewers.

“We’re pretty confident that, the more TV you watch, the more media you consume, the more likely it is that media ― almost like radiation ― builds up,” Darnell Hunt, director of the Ralph J. Bunche Center for African American Studies at UCLA, told The Huffington Post. “And the accumulated effect is to make you feel that what you’re seeing is somewhat normal.”

“What you see often becomes a part of your memory,” echoed Ana-Christina Ramón, assistant director of the Bunche Center, “and thus a part of your life experience.”

It can even serve as a proxy for experiences audience members haven’t actually lived, shaping their views on people of color and women ― and shaping the way those people view themselves.

“There’s this body of research and a term known as ‘symbolic annihilation,’ which is the idea that if you don’t see people like you in the media you consume, you must somehow be unimportant.” Nicole Martins of Indiana University

We spoke to several sociologists and researchers about the power of representation, and what the lack of it might mean for people who don’t see themselves up there on the screen. Since the 1960s, research has found expressions of unequal power in media that, according to Michael Morgan, can be “very dangerous” and “very damaging” to people watching.

“I think the moral argument is self-evident. Stories matter,” Morgan, former professor emeritus at the University of Massachusetts at Amherst and author of dozens of reports on media effects, told HuffPost.

“Stories affect how we live our lives, how we see other people, how we think about ourselves.”

That sentiment was common among the researchers we spoke to, although all of them noted that the sociology of representation is a topic infrequently covered specifically. It comes down to a problem common in academia ― the problem of finding subjects and funding, as mentioned by Glenn Sparks of Purdue University and Nicole Martins of Indiana University. Simply put, it’s costly to look into media effects in a large enough group of people over a long enough period of time.

Martins managed to co-author one study, however, about television’s effect on self-esteem with Kristen Harrison of the University of Michigan, published in 2012. Focusing on children, the pair found that TV made subjects feel good about themselves ― if those subjects were white boys. Girls and boys of color, on the other hand, reported lower self-esteem as they watched.

“We feel pretty comfortable that it’s this lack of representation that could be responsible for this effect,” Martins said.

“There’s this body of research and a term known as ‘symbolic annihilation,’ which is the idea that if you don’t see people like you in the media you consume,” she explained, “you must somehow be unimportant.” (In a 1976 paper titled “Living with Television,” researchers George Gerbner and Larry Gross coined the term with a chilling line: “Representation in the fictional world signifies social existence; absence means symbolic annihilation.”)

In Ramón’s words, “You may wonder, ‘Do I matter? Does society value me as a person?’”

The cathartic experience of finally relating to a character on screen has inspired heartfelt essays. As part of a HuffPost series called “When Representation Mattered,” our own Zeba Blay, who is black, explained how she felt empowered by the Spice Girls’ Melanie Brown. “She was unapologetically loud and unapologetically fierce in a way that (in my mere 10 years) I had never seen a black girl have the permission to be,” Blay wrote. HuffPost’s Carol Kuruvilla, whose family hails from India, described how the soccer flick “Bend It Like Beckham” made her feel less alone by not forcing its Indian protagonist to conform to a trope. “Jess wasn’t just the nerdy best friend, the submissive shy girl, or the exotic temptress (all tropes that are far too common for Asian women),” Kuruvilla explained.

Character tropes ― molds that shape dialogue and casting decisions to produce the nerdy Asian math student, the sassy black sidekick, the icy female boss ― do their own damage, too.

For the underrepresented, seeing a character who looks like them can have a limiting effect if that character is restricted to behaving only in certain ways, which don’t reflect the breadth of their life’s experience. If you are a black, Asian or Latinx person who sees an “inauthentic” or “one-dimensional” version of yourself, Ramón explained, you “may wonder if that is all that is expected of you in society.”

“Visual media teaches us how the world works and our place in it,” she said.

“When you don’t see people like yourself,” Morgan echoed, “the message is: You’re invisible. The message is: You don’t count. And the message is: ‘There’s something wrong with me.’”

“Over and over and over, week after week, month after month, year after year, it sends a very clear message, not only to members of those groups, but to members of other groups, as well,” he said.

Rebecca Sapp via Getty Images Actors Dev Patel, Mahershala Ali, Janelle Monáe, Naomie Harris and Ruth Negga -- pictured here with Aaron Taylor-Johnson, Stephen Henderson and Simon Helberg at the Santa Barbara Film Festival -- are some of the actors up for Oscars on Sunday.

To all viewers, on-screen representation serves as an important (if undervalued) way to glean information about the world. Hunt pointed to decades-old research out of the University of Pennsylvania that showed a correlation between a range of topics as presented on TV ― violence, integration, women’s rights ― and how people thought about those issues in real life. Over time, they found that people who watched more TV embraced what they called the “TV view of the world.”

“And if the ‘TV view of the world’ was violent, then people assume that the world was more violent,” Hunt said.

And perhaps they would, say, vote for a presidential candidate who claims the nation is drowning in a wave of violent Latinx trespassers because that’s how they look on screen. Or believe that America is mostly over racism because there are secondary black characters in films. Or continue to live their lives not realizing Asian men are, indeed, quite attractive.

“Entertainment provides the seeds under which these things make sense to people, because they’ve seen a thousand images of ‘Latinos are violent,’ or ‘Asians are invisible,’ or ‘blacks are this’ or ‘women are that,’ so it is so easy to exploit,” Morgan said, “because it’s a knee-jerk reaction. It’s this, ‘Oh yes, yes, of course. I know that.’”

Viewers might not think that the shows and films that enrich our lives and let us happily escape after a day or week of the usual routine may affect our view of our neighbors, fellow citizens, or people around the world. And it’s true that Middle Ages fantasy with a reputation for bloodshed or a tap-dancing couple in a sunny dreamland, on their own, might not have too much of an impact. But they are part of a much larger force that consistently dilutes the richly diverse experiences of lives enjoyed by people of color and women.

“We can sit by as this continues for another decade,” wrote some of the researchers who diligently record the makeup of the on-screen population, in a recent report, “or can act to ensure that equality and inclusion are the hallmark of entertainment in the years to come.”

Because it’s not just “not fair.” It’s not right.