The study, published in the journal of Cyberpsychology, Behavior, and Social Networking, measured the emotional and physical responses of 30 university students during three different experimental sessions.
The participants, who were between the ages of 19 and 25, first studied a sequence of panoramic pictures, then browsed Facebook, and, lastly, completed a reaction-time test and math problem. Along with recording neural activity, researchers measured heart rate, breathing rate, pupil dilation, and other bodily responses.
The results revealed that a particular psychophysiological pattern can be linked to Facebook use, in the same way that relaxing and stressful situations each generate different emotional and physical reactions.
Furthermore, this particular type of pattern found in the study's participants was one of elevated excitement and engagement -- or "high positive valence and high arousal" -- while surfing Facebook, aligning with what the study calls a "core flow."
These findings led scientists to conclude that "the success of SNSs [social-networking sites] might be addressed also to the ability they have in inducing positive emotional experiences," which are what draw people back again and again.
In addition to positive social-networking vibes, most Facebook users often get more than they give, according to a report from the Pew Internet and American Life Project. On average, users receive more friend requests than they send, are tagged in photos more often than they tag others, and have their content liked more than they like others' posts -- all incentives for users to come back for more.
Pew researchers noted that these interactions contribute to "social well being."
"Making friends on Facebook is associated with higher levels of social support," the Pew study read. "Those who made the most frequent status updates also received more emotional support."
The exception to the rule are a small group of extremely active users -- or "power users," as Rutgers professor and lead author of the report, Keith Hampton, calls them -- who give more than they get rather than get more than they give.
"There is this 20 percent to 30 percent who are extremely active who are giving more than they are getting, and they are so active they are making up for feeding everyone extra stuff," Hampton said, as reported by the LA Times.
But sometimes too much of a good thing can become a problem. Many repeated visits and excessive time spent on sites like Facebook could override positive effects. A different study, also published in the Cyberpsychology, Behavior, and Social Networking journal, reveals that those who have used Facebook longer and who spend more time on the site often have a skewed perception of others' lives and a less positive outlook on their own lives.
In this Utah Valley University study, researchers sent out questionnaires to 425 undergraduate students. They were polled on how many years they've used Facebook, how much time they spend on the site each week, how many Facebook friends they have, and other aspects of their Facebook use.
The researchers' analysis showed that "those who have used Facebook longer agreed more that others were happier, and agreed less that life is fair, and those spending more time on Facebook each week agreed more that others were happier and had better lives."
While there is a chance that one could become addicted to social-networking sites, perhaps the best any of us can do is use them all in moderation.