It’s been known for some time that people share things on social media – a lot – without reading them first. The writer Alex Balk recently compared Facebook to “the coffee table on which people placed their unread copies of Thomas Piketty’s Capital”: when we share, we’re often really focused on promoting a certain image. But a new study goes further: apparently, sharing things, or just having the option to share, undermines the ability to digest and remember them. (Participants were twice as likely to make errors in a comprehension test.) When your attention is partly occupied by thoughts of how you’ll share or discuss what you’re reading, it’s a distraction from actually reading it – made worse, presumably, if your newsfeed’s also scrolling by in the corner of your eye. Social media is like belonging to a book club, but only ever reading novels while you’re at the book club, two glasses of cabernet the worse for wear.

The only surprise is that any of this comes as a surprise. It should be obvious that attention is a limited resource (that’s why people crash when they text and drive) yet we rarely treat it like other such resources. If a major corporation took £10 from your bank account daily, for no benefit, you’d be furious. But as Matthew Crawford points out in his book The World Beyond Your Head, the same corporation can help itself to your attention with a loud TV ad in an airport lounge, dragging your focus from conversation. Indeed, we actively collaborate with attention theft: iPads that let you jump from your novel to the web or to FaceTime chat are more popular than e-readers that won’t. In a culture that viewed attention differently, we might pay extra for such limitations. Instead, we act as if our attentional capacities are infinite, then feel scattered and exhausted when it turns out they aren’t.

You can deal with the situation by denying there’s a problem, as some pundits like to do; or you can take draconian measures, quitting social media for ever, or going on digital detox retreats. But I prefer the middle path encapsulated in the Buddhist idea of “guarding the sense doors”. The world stakes its claims on our attention, this argument goes, through the “sense doors”, chiefly the eyes and ears. So it’s wise to employ a doorman. (I imagine a firm but polite butler, not a bouncer on steroids.) You don’t need to nail the door completely shut, as Facebook quitters do; you just need to stay mindful of who’s trying to get in.

In practical terms, this means not mixing attentional modes: read when you’re reading, share when you’re sharing. You could send articles you discover online to Instapaper or Evernote, read them later offline, then treat sharing as a discrete task, perhaps at a specific time. This may not mean always being narrowly focused on one task; plenty of social situations need “wide-angle” attention instead. But it does mean not trying to use attention simultaneously for two incompatible tasks. Let one visitor across the threshold at a time. The others will wait on the doorstep. Or, better yet, wander off and stop pestering you.

oliver.burkeman@theguardian.com