Increased word spacing improves performance for reading scrolling text with central vision loss

Hannah Harvey, Stephen J Anderson, Robin Walker

Research output: Contribution to journalArticlepeer-review


SIGNIFICANCE: Scrolling text can be an effective reading aid for those with central vision loss. Our results suggest that increased interword spacing with scrolling text may further improve the reading experience of this population. This conclusion may be of particular interest to low-vision aid developers and visual rehabilitation practitioners. PURPOSE: The dynamic, horizontally scrolling text format has been shown to improve reading performance in individuals with central visual loss. Here, we sought to determine whether reading performance with scrolling text can be further improved by modulating interword spacing to reduce the effects of visual crowding, a factor known to impact negatively on reading with peripheral vision. METHODS: The effects of interword spacing on reading performance (accuracy, memory recall, and speed) were assessed for eccentrically viewed single sentences of scrolling text. Separate experiments were used to determine whether performance measures were affected by any confound between interword spacing and text presentation rate in words per minute. Normally sighted participants were included, with a central vision loss implemented using a gaze-contingent scotoma of 8° diameter. In both experiments, participants read sentences that were presented with an interword spacing of one, two, or three characters. RESULTS: Reading accuracy and memory recall were significantly enhanced with triple-character interword spacing (both measures, P ≤ .01). These basic findings were independent of the text presentation rate (in words per minute). CONCLUSIONS: We attribute the improvements in reading performance with increased interword spacing to a reduction in the deleterious effects of visual crowding. We conclude that increased interword spacing may enhance reading experience and ability when using horizontally scrolling text with a central vision loss.

Original languageEnglish
Pages (from-to)609-616
Number of pages8
JournalOptometry and Vision Science
Issue number8
Early online date17 Jul 2019
Publication statusPublished - 1 Aug 2019

Bibliographical note

© 2019 American Academy of Optometry. Increased Word Spacing Improves Performance for Reading Scrolling Text with Central Vision Loss. Optometry and Vision Science. 96(8):609-616, August 2019.


Dive into the research topics of 'Increased word spacing improves performance for reading scrolling text with central vision loss'. Together they form a unique fingerprint.

Cite this