03/19/2013 10:33 am ET Updated May 19, 2013

Why Happy Beats Sad On Social Media: It's Built That Way

Like it or not, you have little choice but to "like" this.

In a recent New York Times story "Good News Beats Bad on Social Networks," John Tierney examines a series of studies by neuroscientists and social psychologists that probed word-of-mouth sharing online. Taken together, the findings suggest happy news spreads more quickly, to more people, than depressing bulletins, and Tierney trots out several psychological and scientific explanations for our behavior, including brain scans, our need for arousal and theories on our social consciousness.

But there's another key factor at play that Tierney doesn't address: Social networks are engineered to lubricate sharing the happy stuff.

The social web offers an infrastructure designed to facilitate digital back-patting and high-fiving, so it's small wonder it's the good news that travels so far, so fast.

Consider even the vocabulary of the internet's most popular social sites. The language and symbols read like they've been penned by cheerleaders on an unhealthy dose of uppers: It's a mess of hearts, stars and thumbs-ups accompanied by nudges to "like," "favorite" or "digg" whatevers in front of you. Of course people can post what they choose to the blank canvases of sites like Twitter, Tumblr and YouTube, but the tools for instantaneous sharing feature cheery, laudatory language ill-suited for passing along grim news about a deaths, rapes or natural disasters.

After all, can you really in good faith "like" a story about spousal abuse to post it to Facebook? News sites, including The Huffington Post, will often replace Facebook's "like" with a "recommend" button for more sensitive stories, yet even then readers can appear to "recommend" a fatal food poisoning outbreak or disastrous tsunami. (I'm also reminded of a time several years ago when a friend posted about his break-up on Facebook. Someone else "liked" it. "That's awkward," my newly single friend commented in response.)

Twitter, which has, to a greater degree than Facebook, invented its own terminology for sharing, offers people the seemingly innocuous options to tweet, "favorite" or "retweet." The "favorite" button -- a small star that lights up yellow -- seems tone deaf for a tweet about, say, a school shooting, and accordingly people often lash out at Twitterers who make offensive or controversial tweets a "favorite." Retweets in turn have become so synonymous with a kind of digital pat-on-the-back that countless Twitter bios include the caveat, "retweets are not endorsements." Re-posting someone's bad news feels more exploitative than empathetic.

It's actually Reddit, the social site that takes more heat than any other for hosting unsavory content about rape fantasies or, that seems to have the most neutral sharing lingo of all: the "upvote."

Of course, on sites like Facebook, YouTube, Twitter and Tumblr, there's always the comment box -- the repository for all other reactions, the small square in which to reflect on all the other things you felt for a story, besides "like." Yet the high-impact, short-duration nature of our interactions on social networks further hinder the spread of sob stories, which simply take more time to consider, share and talk about, given the additional context that's frequently necessary. There's no LOL-like shorthand for "really upset by this" (RUBT?). Even for digital natives and social media addicts fluent in internet shorthand, an emoticon or Emoji next to a post about scandal, sickness or death seems crass.

By and large, social media services have focused on providing us with the tools to spread our successes, make funny videos go viral and share OMG moments, while essentially ignoring the messy, depressing stuff that can't be "heart"-ed or given the thumbs-up.

Tierney, and the research he cites, may be giving us altogether too much credit in the matter of deciding what we share, given that social sites are socially engineered for the good stuff. Their business models depend on it: Brands no doubt prefer to display their wares and brand messages next to posts about miracle breakthroughs and genius animals, rather than by links about school shootings or car crashes.

The triumph of good news over bad online has every bit as much to do with what social networks want as it does with what we want.

After all, for years, Facebook users have clamored for a "dislike" button. Their only way to demand it is through the affirmative: The "Dislike Button" Facebook page, which demands a way to give friends' posts the thumbs down, has over 54,000 likes.