Improving paragraph reading: The effect of beginning-of-line additions in readability, an eye tracking experiment

Abstract

From a perceptual point of view, a paragraph is a very complex and tangled unit of information. Paragraphs contain a multitude of shapes that can’t be interpreted all at once. Precise navigation is thus essential. The present research tests three conditions expected to affect navigation within paragraphs, both based on previous literature and editorial design history. In the 15th century, a common practice was to add the first word of the next page at the bottom of the current one (De Hamel, 1992). Contemporary research has shown within a block of text, line differentiation greatly affects its readability, as return sweeps (the eye-movement to transition between lines) can be performed more precisely (Bhatia et al., 2014; Rello et al., 2016). The present study therefore looks at how additional elements at the beginning of each line affect readability. Following intuitive knowledge from the typesetting community, the repeating of words was considered. Two design choices - one embedded and one outside were used. Another line differentiation condition, which involved a graphic addition (diamonds before each line) was also studied. It was expected to observe an improvement in reading performance against a control condition. Results showed considerable reduction in reading time, amount of fixations and leftward saccades for the diamond condition against control. The two text addition conditions, though, performed worse than control. These results show word repetition is not useful, as it seems to add cognitive load. Meanwhile, simple and distinct shapes before lines do help. Conclusions align with previous research, which suggests back sweep performance is linked with parafoveal information (Slattery & Parker, 2016), visual area in which reading acuity is at a lowest (Sandberg et al., 2008).