Assessing the viability of monospaced fonts for eye-movement paradigms in Arabic reading

Monospaced (fixed-width) fonts such as , where each character occupies an identical unit of horizontal space, are widely used in eye-movement research in Latinate languages (Slattery, 2016). The uniformity of monospaced fonts is methodologically advantageous, allowing researchers to match the spatial width of words containing equal numbers of letters. However, their use has been avoided in Arabic research due to their rarity and perceived unnatural appearance, which changes the natural cursive interconnection between letters (Hermena et al., 2017). This imposes difficulties for researchers of Arabic reading, particularly when employing gaze-contingent change techniques, creating restrictions that impede progress to close the gap in knowledge about cursive languages. While it has been hypothesized that monospacing may interfere with cognitive processing, this has not been directly investigated. In two experiments, we examined whether monospaced and proportional fonts modulate lexical frequency effects and parafoveal preview effects during Arabic sentence reading. Fixation time measures showed similar patterns in both font types. Lexical frequency influenced word identification similarly across most measures in the two font types (Experiment 1), while a manipulation of parafoveal preview validity produced comparable effects on fixation times for target words (Experiment 2). Across experiments, monospaced fonts produced shorter but more frequent fixations than proportional fonts: a trade-off that mirrors effects previously reported in Latinate languages. Given the methodological advantages for gaze-contingent paradigms, these findings establish monospaced fonts as a readable and suitable option for Arabic reading research, facilitating tighter spatial control and cross-script comparability.