1 Introduction
Over the past two decades, digital technologies have fundamentally altered how people are
exposed to and engage with information. The internet has enabled content to be created
and shared with large audiences at marginal cost, social media have blurred the lines
between personal and mass communication and search engines have made vast amounts
of information widely, instantly and freely accessible.
More recently, the optimism about the positive transformative potential of digital technologies has given way to an acute sense of its risks: a risk, for instance, of filter bubbles
and echo chambers, polarising society along ideological lines and fragmenting the political
discourse; or a risk of nefarious actors spreading misinformation online, wielding undue
influence and undermining democratic processes.
However, researchers can now learn how people interact with their information environment at an unprecedented scale and level of detail by analysing massive amounts of data
about who sees, reads or writes what, when and where. This allows them to evaluate
the benefits and risks of digital transformations. It also enables them to reassess more
fundamental cognitive mechanisms of engaging with information and to develop new hypotheses about the operation of these mechanisms in the digital age. Going forward, good
research will have to understand these transformations and how they recontextualise a
long history of literature in the field. This makes a review both timely and necessary