In May, two months after Fox announced it would reboot “The X-Files,’’ Gillian Anderson appeared onstage with David Duchovny during his band’s show at the Cutting Room in New York City. Pictures were taken of the costars embracing and having a quick kiss. When I saw those pictures, I squealed and Googled their current marital statuses — because I wanted them to date.

I know the reaction was silly and misguided; what I really want is for their characters, Fox Mulder and Dana Scully — who return Sunday at 10 p.m. on Fox — to be in love. Based on the very little I know about the personal lives of Duchovny and Anderson, there is no reason for them to be a couple. But there is a part of my brain that likes the idea of it — the same part that was thrilled when I first read that “Twilight’’ stars Robert Pattinson and Kristen Stewart were dating in real life.

I’m not the only person who feels a strange desire to want actors who play couples to fall in love off-screen. Fans like to fantasize about this kind of thing, and it’s one of the most common (and mindless) questions asked of actors who play lovers. A few weeks ago, “Outlander’’ stars Sam Heughan and Caitriona Balfe — who share steamy, naked scenes as Claire Beauchamp and Jamie Fraser on the Starz time travel show — were asked by E! whether they were together in real life.

“We’re not together. . . . I’m sorry to break people’s hearts,’’ the actress answered. “They like to try to maybe replicate the Claire and Jamie story. But I think it would be difficult for us to work together and be together.’’

Heughan added, “Because I think people buy into the show and us saying it’s not real, they feel like they’ve been duped. It’s like, ‘You acted it. You lied to us!’ And I’m like, ‘Well, sorry!’’’

Maybe we fans and reporters fall back on this question again and again because we’re not actors, so we can’t imagine kissing our co-workers. Maybe we just don’t understand how faking attraction can be part of a job.

But according to experts, we might also long for these stars to be together because of our brains and how we process information.

Uri Hasson, associate professor in the psychology department and Neuroscience Institute at Princeton University, explains that when you experience something in real life, you process the information in a specific part of your brain. You use that same part of your brain to process an experience when it is explained or simulated for you.

“We like stories and movies because we like to experience simulations. [Television and films] simulate for us what could happen.’’

Our brains should know the difference between truth and fiction, but if we process simulations the same way we do experiences, falling for a fictional couple onscreen might trigger the desire for the simulation to become real, he says. It’s a jump, but it’s possible.

Mark J. Williams, associate professor of film and media studies at Dartmouth College, says that the desire could be biological, but he thinks it’s more cultural. He understands that there’s an instinct to “ship’’ (a verb of recent coinage: the act of wanting two characters/people to be in a relationship). But he says that my “shipping’’ not just, say, “Moonlight’’ characters David Addison and Maddie Hayes, but also actors Cybill Shepherd and Bruce Willis, might have been about my need for narrative closure.

Maybe I want “Sherlock’’ stars Benedict Cumberbatch and Martin Freeman to fall in love, or am excited that “The Americans’’ stars Matthew Rhys and Keri Russell are together, because the couplings are an extension of what I (and other fans) have defined as an appropriate ending.

He also says that I might root for these real-life couples on television or in film franchises such as “Twilight’’ — as opposed to stand-alone movies — because I’ve spent so many hours watching the same actors play the same characters.

“The amount of time that’s involved ... you start to wonder if there’s another level to this relationship,’’ Williams said.

He also brings up social media. These days, actors often have an online persona. Some of them live-tweet their own television shows. That makes the lines even blurrier.

Ken Feil, senior scholar-in-residence in Emerson College’s Department of Visual & Media Arts, explains via e-mail that the answers to the real-life shipping might lie in Richard Dyer’s 1986 book “Heavenly Bodies.’’

Feil says Dyer writes “that we love stars devotedly and enduringly due to the fact that they repair a sense of fragmentation in our lives caused by modernity. We all have a public self and a private self, very useful to be sure in terms of organizing our lives and identities (work versus home, for instance), yet also a cause of anxiety and confusion over the sense of being split: Which self is the ‘real’ one? Is there a ‘real’ me?’’

Feil continues, “Stars help repair that existential fragmentation because their stock-in-trade is the demonstration of the private self on a the most public platform of mass culture. As a logical extension, we desire stars to merge public and private further by collapsing their public selves with their private selves.’’

He theorizes that this could be why I’m so bummed when I find out costars don’t even like each other.

“Is it disappointing because it reminds us of our own fragmentation?’’ he asks.

Of course, this desire to see actors together might just be about the wish for fiction to come true. Hasson says that’s a strong possibility — that perhaps I wanted Stewart and Pattinson to be together because if their love was real, maybe hot vampires could be, too. And in the case of “The X-Files,’’ if Anderson and Duchovny can fall in love, maybe Mulder and Scully could exist. Maybe the truth is out there.

As Hasson puts it, “You want to believe.’’

Meredith Goldstein can be reached at Meredith.Goldstein@Globe.com.