Reading Speed Does Not Benefit from Increased Line Spacing in AMD Patients

Abstract

Purpose Crowding, the adverse spatial interaction due to the proximity of adjacent targets, has been suggested as an explanation for slow reading in peripheral vision. Previously, we showed that increased line spacing, which presumably reduces crowding between adjacent lines of text, improved reading speed in the normal periphery (Chung, Optom Vis Sci 2004;81:525–35). The purpose of this study was to examine whether or not individuals with age-related macular degeneration (AMD) would benefit from increased line spacing for reading. Methods Experiment 1: Eight subjects with AMD read aloud 100-word passages rendered at five line spacings: the standard single spacing, 1.5×, 2×, 3×, and 4× the standard spacing. Print sizes were 1× and 2× of the critical print size. Reading time and number of reading errors for each passage were measured to compute the reading speed. Experiment 2: Four subjects with AMD read aloud sequences of six 4-letter words, presented on a computer monitor using the rapid serial visual presentation (RSVP) paradigm. Target words were presented singly, or flanked above and below by two other words that changed in synchrony with the target word, at various vertical word separations. Print size was 2× the critical print size. Reading speed was calculated based on the RSVP exposure duration that yielded 80% of the words read correctly. Results Averaged across subjects, reading speeds for passages were virtually constant for the range of line spacings tested. For sequences of unrelated words, reading speeds were also virtually constant for the range of vertical word separations tested, except at the smallest (standard) separation at which reading speed was lower. Conclusions Contrary to the previous finding that reading speed improved in normal peripheral vision, increased line spacing in passages, or increased vertical separation between words in RSVP, did not lead to improved reading speed in people with AMD.

Size or spacing: Which limits letter recognition in people with age-related macular degeneration?

“…Recent psychophysical evidence shows that when the disorder has been present for a long time, many people with AMD exhibit characteristics that are more similar to those usually found in the normal fovea, and different from those usually observed in the normal periphery. Such evidence includes the lack of a benefit of reading text with line spacing greater than the standard (Chung et al, 2008; Calabrèse et al, 2010), 4 and that the crowding zone measured at the PRL used by people with AMD is isotropic as in the normal fovea (Toet & Levi, 1992); instead of anisotropic in shape (Chung, 2013b). The changes observed in some spatial properties at the PRL of people with AMD have been attributed to the plasticity of the visual system.…”

Binocular Reading Speed with Increased Vertical and Horizontal Word Spacing in Normal and Low Vision

“…Bentley 10 , Peterson and Tinker 11 , examined the effect of line spacing on reading speed and concluded thatincreased vertical word spacing, benefits reading speed.Similar result is obtained in present study but up to a spacing of 3x Calabrese A. et.al. 15 concluded that increasing interline spacing is advisable only for very slow readers (<20 words/min) who want to read a few words (spot reading). Vertical crowding does not seem to be a major determinant of maximal reading speed for patients with central scotoma while Chung ST 15 et al concluded that increased line spacing in passages, or increased vertical separation between words in RSVP (rapid serial visual presentation), did not lead to improved reading speed in people with AMD.Rubin GS 9 statedthat line width and typeface have little influence on reading speed in people with mild to moderate sight problems.In our study, we have not considered specific group of disease but overall low vision subjects.…”

“…15 concluded that increasing interline spacing is advisable only for very slow readers (<20 words/min) who want to read a few words (spot reading). Vertical crowding does not seem to be a major determinant of maximal reading speed for patients with central scotoma while Chung ST 15 et al concluded that increased line spacing in passages, or increased vertical separation between words in RSVP (rapid serial visual presentation), did not lead to improved reading speed in people with AMD.Rubin GS 9 statedthat line width and typeface have little influence on reading speed in people with mild to moderate sight problems.In our study, we have not considered specific group of disease but overall low vision subjects. Future studies are required in low vision subjects to assess reading speed in central and peripheral field loss separately.…”

The effect of motion on crowding: Zooming text

“…Past attempts to improve peripheral reading via crowding reduction have generally focused on introducing spatial changes to the stimulus, such as increasing letter spacing (Chung, 2002), enlarging the spacing between lines of text (Bernard, Anne-Catherine, & Eric, 2007;Calabrèse et al, 2010;Chung, 2004;Chung, Jarvis, Woo, Hanson, & Jose, 2008), and decreasing the spatial similarity of adjacent letters (Chung & Mansfield, 2009). However, despite the critical importance of spacing and spatial similarity to crowding, these manipulations have limited effectiveness in improving peripheral reading.…”