The effects of visual crowding, text size, and positional uncertainty on text legibility at a glance. (July 2018)

• Record Type: Journal Article
• Authors: Dobres, Jonathan; Wolfe, Benjamin; Chahine, Nadine; Reimer, Bryan
• Is Part Of: Applied ergonomics. Volume 70(2018)
• Page Start: 240
• Page End: 246
• Publication Date: 2018-07
• Subjects: Typography -- Legibility -- Visual crowding; Human engineering -- Periodicals; 620.82
• DOI: 10.1016/j.apergo.2018.03.007
• Languages: English
• ISSNs: 0003-6870

Abstract

Abstract: Reading at a glance, once a relatively infrequent mode of reading, is becoming common. Mobile interaction paradigms increasingly dominate the way in which users obtain information about the world, which often requires reading at a glance, whether from a smartphone, wearable device, or in-vehicle interface. Recent research in these areas has shown that a number of factors can affect text legibility when words are briefly presented in isolation. Here we expand upon this work by examining how legibility is affected by more crowded presentations. Word arrays were combined with a lexical decision task, in which the size of the text elements and the inter-line spacing (leading) between individual items were manipulated to gauge their relative impacts on text legibility. In addition, a single-word presentation condition that randomized the location of presentation was compared with previous work that held position constant. Results show that larger text was more legible than smaller text. Wider leading significantly enhanced legibility as well, but contrary to expectations, wider leading did not fully counteract decrements in legibility at smaller text sizes. Single-word stimuli presented with random positioning were more difficult to read than stationary counterparts from earlier studies. Finally, crowded displays required much greater processing time compared to single-word displays. These results have implications for modern interface design, which often present interactions in the form of scrollable and/or selectable lists. The present findings are of practical interest to the wide community of graphic designers and interface engineers responsible for developing our interfaces of daily use. Highlights: This study examines the legibility of crowded and isolated text displays. Legibility was measured as the amount of time needed to read text accurately. Typeface size, inter-line spacing, and crowdedness were compared. Larger text with wider leading was found to be most legible. Findings have implications for practical display designs.