When singer Whitney Houston died in February, expressions of grief and solidarity surfaced quickly. Facebook status updates, tweets and related postings captured shared expressions of mourning for a person many of the social media users had never met. Similar results occurred with the recent deaths of Adam Yauch of the Beastie Boys and television host and producer Dick Clark, among others.

The common responses to celebrity deaths demonstrate important realities about how people build relationships with the media they consume, according to a Kansas State University cognitive psychologist. Richard Harris, professor of psychology, has studied a number of aspects of the psychology of mass communication. His focus has been on how people acquire knowledge from media. Among his studies has been an examination of how watching certain media with different people influences the experience. He has also studied how people remember certain media experiences.

Harris says many people develop relationships with media characters in a similar manner to how they do so in real life. This phenomenon is referred to as parasocial interaction. The one-sided relationship is most commonly observed between celebrities and their fans. A prominent example cited by Harris was the popular television show "Friends." The show aired for 10 years and revolved around six principal characters.

"Many people have probably spent more time with the characters on 'Friends' than they have with most of their real-life friends," Harris said. "Of course they haven't interacted with them -- it's very one-sided. People can, if drama is particularly well acted and written, identify with the characters. That's a significant relationship. That becomes particularly acute often when a character dies or a famous person dies with whom you have such a relationship with."

Spontaneous displays of grieving after the death of a famous person or celebrity are not new. For example, impromptu memorials appeared for Princess Diana, Michael Jackson and John Lennon following their deaths.

Harris said these losses have a distinct difference from the loss of a family member.

"We don't have the social structures and support for grieving the loss of a media character or, in particular, a fictional character," Harris said. "Somebody's real upset that their favorite soap opera character was killed off yesterday and they tell someone about that and they laugh. It's a very different reaction than if their grandmother had died."

As a result, social media postings can turn therapeutic for some devoted fans or supporters, Harris said. Fellow celebrities have also taken to social media sites and other mediums to mourn the loss of fellow stars or influential people.

While parasocial interaction was first written about as early as the 1950s, instances only began increasing with the rise of television and movies and the more realistic depictions of fictional characters.

"Both have the visual and auditory modality," Harris said. "Television and movies look a lot more real than radio or print media. I think the degree of identification and emotional response is much greater."