I've been seeing a trend in the online news and data visualization world of presenting information paired with some sort of data that changes dynamically as you scroll down.
Here is an example from The Gardian: https://www.theguardian.com/us-news/ng-interactive/2015/oct/19/homan-square-chicago-police-detainees
And another one from Bloomberg : https://www.bloomberg.com/graphics/2015-measles-outbreaks/
My hypothesis is that this model of presenting information will negatively affect scannability of the content as well as be very disruptive to reading. However, I do not have any evidence. If you have evaluated something similar, please share.