If Elvis were alive, he'd be 75 on Friday. While his musical style and gyrations may have been unique, Elvis Presley's stardom and swooning fans can be explained by simple psychology, trends in technology and pop culture, and a look at our ancestors, all of which reveals why celebrity worship is on the rise.

"The Elvis phenomenon is only a case study of a wider psychological phenomenon," said James Houran, a clinical psychologist and president of 20/20 Skills, a human resources company.

For obvious reasons — success, loads of money, looks — many people look up to celebrities, even after they've passed away. But other factors come into play, including:

  • Personality type.
  • Religion (the highly devout are less likely to worship stars).
  • Psychological state (lonely individuals can take comfort in having a fantasy relationship with a star).

We can also look to our ancestors to explain celebrity worship. Humans are social beings who crave interaction with others, and we pay closest attention to the prestigious.

"We'll find those social relationships even when they're imaginary or illusory," said Adam Galinsky, professor at the Kellogg School of Management at Northwestern University. "Social hunger is really like ordinary hunger. It constantly needs to be satisfied but its satiation is short-lived."

That sector of the population most obsessed with celebrities, to varying degrees, is growing as a result of technology that lets us follow the George Clooney's of the world in nearly real-time along with a rise in our society's narcissism, psychologists say.

Translation: Elvis impersonators and the like are here to stay.

Celebrity stalkers

The degree of star-struckness goes from the healthy dose of flipping through People magazine to overboard and what scientists would categorize as a psychosis. 

"There are people who really follow this stuff and find a celeb they really dig; they have Google alerts for them and they treat them like a friend or relative," said Cooper Lawrence, an expert on celebrity culture and fame. "Then there's a small percentage who [are] celebrity obsessed, where they really feel the celebrity is really talking to them," said Lawrence, who is the author of "The Cult of Celebrity" (skirt! Publishing, 2009).

Elvis impersonators, she said, likely straddle these two levels.

The growing phenomenon of celebrity worship is affecting today's kids, too. Research reported in 2006 suggested celebrities dominated the interests of 7- to 11-year-olds even more so than toys and other products marketed to them. The researchers partly attributed the phenomenon to "our celebrity-obsessed society."

Celebrity ancestors

Putting the rich and powerful on pedestals is nothing new.

"Every culture has its royalty of some sort and since we don’t have any legitimate monarchy somebody has to serve that function," said Stuart Fischoff, emeritus professor of media psychology at California State University, Los Angeles, adding that we can look up to and even down on (when they slip up) these royal figures.

Fischoff also noted the Greeks and Romans had their own celebrities — Olympian gods.

"Cultural anthropological and historical studies show us that human societies have always had a need to 'worship' things — and sure enough this was often special people in society — the best hunters, athletes, the most beautiful, the smartest, the most spiritual," Houran said.

As far back as our non-human ancestors, scientists have found evidence of focusing on the prestigious. That way, they would know how to gain rewards or avoid punishment, Galinsky said. He noted a study in which non-human primates gazed more at alpha males than others.

Why we dig celebs

The growing obsession with celebrities that are arguably not as worthy as, say, a great hunter-gatherer, is the result of various factors. For one, stars are right in front of our faces, being splashed across screens and in every form of media, according to Houran. Many of us like what we see and want to emulate that.

"Celebrities appear successful and are typically beautiful — qualities that naturally attract others because people tend to copy those who seem to have what we want," Houran told LiveScience.

Also "people quickly form illusory 'relationships' with celebrities since we learn much about them personally and feel we can relate to them in ways that maybe we cannot with our real friends and family," Houran said.

Some fans develop what they consider a real relationship with their celeb of choice. "They have a sense that, 'I am connected with that person, they know me and I know them,'" Fischoff said. "But the reality is it's a one-way street — they don't know who you are, unless you become a stalker."

A study published in a 2008 issue of the journal Personal Relationships showed that these one-sided relationships with celebrities could help low self-esteem individuals look at themselves more positively.

And indeed, social doors do open. "Some people make their lives have meaning because of their relationship with that celebrity. They develop a social network with other people who like that celebrity."

For the extreme fans, getting the scoop on their favorite famous person gives them a high.

"And finally for many people celebrity worship acts similar to addiction," Houran said. "Just like an addict developing a psychological or physical tolerance to a chemical substance, celebrity worshippers appear to need to endorse increasingly more intense or extreme attitudes and act out increasingly more intense or extreme behaviors in order to continue to feel connected to their favorite celebrity … or get a 'high' from celebrities."

Extreme worship

Some people take celebrity watching more seriously, according to research.

For instance, religion matters. "The less religious you are the more likely you will worship celebrities," Lawrence said. "You'll be able to replace Jesus with George Clooney on some level. That's an extreme." The more religious person would kind of see this obsession as "worshiping false gods," she added.

"Certain people are more likely than others to succumb to the more extreme forms of celebrity worship," Houran said. Younger individuals are a high-risk group, he said, since there's a strong market for such celebrity idols and teens are vulnerable as they are just forming their personal identities.

Houran said others likely to do more than swoon at celebrity sightings would include: people who feel disconnected from society or have experienced a disruption in their identities, such as the recently divorced; depressed individuals; those with poor body image.

And the neurotics. "People who are tense, irritable, moody, antisocial, egotistical and impulsive tend to latch onto celebrities more easily than people low in these traits," Houran said.

On the rise

Scientists say they have reasons to believe celebrity obsession is on the rise.

"People high in narcissism tend to embrace celebrity even more," Lawrence said. "A narcissist believes they are entitled to a certain way of treatment and a certain lifestyle, and who emulates that lifestyle more than a celebrity?" The present rise in celebrity culture, "where everybody is a celebrity, is directly correlated to the rise in narcissism," she said.

Why so many narcissists? Lawrence points to research suggesting some progressive parenting over the last decade or so could be partly to blame.

"Baby boomers and Gen-X parents are so afraid of ruining the self-esteem of their children. Everybody gets a trophy and my daughter is special; everybody has to be treated the same way," Lawrence said. "It's causing more narcissism because it's telling a kid you don't have to do anything to be successful, you just have to be wonderful fabulous you. They're great just for being born."

Then there's technology that's giving us record access to the rich and famous.

"While there has always been celebrity worship, technology has taken it to a heightened level," Houran said.

From entertainment news on TV to celebrity web sites and social media, we are really getting to know these people. 

"It does this by promoting in people the illusion that we can actually know and develop a relationship with celebrities. In essence, people seem to confuse having a lot of information about a celebrity with genuine intimacy," Houran said. "Now, more than ever before, technology allows fans to 'get closer' to their favorite celebrities. That is, the distance between fans and celebrities is getting smaller and smaller."

These huge windows into personal lives that are now so common arguably began with Elvis.

"Elvis really was one of the first to cross over into that type of celebrity," Lawrence said. "He was a singer and actor. He opened up his life to people and people really felt like they knew him."

And while Elvis and John Mayer fans might have similar reasons for their obsessions, today's fans have higher expectations of celebs, Lawrence said. We expect all the intimate details of Mayer's love life, but as for Elvis: "They just wanted him to sing and be cute," she said.