Why do some Internet memes go viral while most others soon sink without a trace? A paper published in Scientific Reports suggests that a model of the competition for individuals’ limited attention in a social network structure may be able to explain the broad diversity of topic popularity and longevity, and user activity on social networking sites such as Twitter.

The advent of social media has enhanced the potential reach of ideas, or memes, but the abundance of information to which many individuals are exposed, via online social networks, is exceeding our capacity to consume it. Lilian Weng, Filippo Menczer and colleagues develop a model of the mechanisms of competition and their role in the diffusion of ideas via social networks, which they validate using data from Twitter, including more than 120 million ‘retweets’ (reposting another user’s message) and involving 1.3 million ‘hashtags’ (topic labels).

Social network structure and our finite attention are both key ingredients of the information diffusion model - excluding either factor leads to results that are inconsistent with the empirical data. Factors such as the intrinsic appeal of a meme can still help determine its popularity, but at the statistical level the authors show it is not necessary to invoke an intrinsic 'worthiness' of memes to reproduce their observed global dynamics.