Scientists claim that you spend more time on the paper version and that you understand and retain the text content more easily. There are a number of explanations for this screen inferiority effect, which, by the way, only occurs when reading non-fiction texts and when reading under time pressure. First and foremost, the inferiority of screen reading apparently results from the fact that we proceed more superficially when reading digital texts, establish supposed coherences more quickly and are too sure too soon that we have understood the content. We read less carefully. All this describes a reading mode that reading research calls „shallow“ or flat reading.
Source : faz.net