The study, carried out by researchers at Switzerland's Ecole Polytechnique Federale de Lausanne and the Federal University of Minas Gerais in Brazil, found evidence that users who engaged with a middle ground of extreme right-wing content migrated to commenting on the most fringe far-right content.

Their paper, with the catchy title "Auditing radicalisation pathways on YouTube", covers a large-scale study of YouTube looking for traces of evidence -- in likes, comments and views -- that certain right-leaning YouTube communities are acting as gateways to fringe far-right ideologies.

The researchers analysed 330,925 videos posted on 349 channels -- broadly classifying the videos into four types: Media, the Alt-lite, the Intellectual Dark Web (IDW) and the Alt-right -- and using user comments as a "good enough" proxy for radicalisation (their data set included 72 million comments). The findings suggest a pipeline effect over a number of years where users who started out commenting on alt-lite/IDW

YouTube content shifted to commenting on extreme far-right content on the platform over time. The rate of overlap between consumers of media content and the alt-right was found to be far lower.

"The researchers were unable to determine the exact mechanism involved in migrating YouTube users from consuming 'alt-lite' politics to engaging with the most fringe and extreme far-right ideologies -- citing a couple of key challenges on that front: Limited access to recommendation data; and the study not taking into account personalisation (which can affect a user's recommendations on YouTube)."

"But even without personalisation, they say they were still able to find a path in which users could find extreme content from large media channels.'"