![]() 19, 27 – 31 In addition, perceptual learning has also shown effectiveness in improving visual functions in adults with amblyopia (monocular sensory loss of vision in the absence of an organic origin). 18 Practically, perceptual learning is synonymous with “training” or “practice.” 19 Previous studies have shown that visual performance improves with practice for a variety of tasks, 19 – 25 in younger as well as in older adults, 26, 27 and in the normal fovea and periphery alike. Perceptual learning is defined as “any relatively permanent and consistent change in the perception of a stimulus array, after practice or experience with this array”. In this study, I explored the feasibility of using perceptual learning, a method that has proven to be effective in improving visual functions in normal and amblyopic visual systems, to improve reading speed for people with central vision loss. Unfortunately, none of these simple manipulations of text typography or typesetting improve reading speed for people with central vision loss. 14 Other attempts have explored whether simple manipulation of text typography and typesetting such as increasing letter spacing 15, 16 and line spacing, 17 which presumably reduces the crowding effect among text, could improve reading speed. 9 – 11 A handful of studies found a small advantage of using RSVP, 12 especially if the word presentation rate varied with word length 13 or when observers were allowed to adjust their own presentation rate. Most studies found no significant differences in reading speed for different text presentation modes for people with central vision loss. 5 – 8 Substantial effort has been invested to determine the mode of text presentation that offers people with central vision loss the fastest reading speed, including page format, scrolling-text in the horizontal or the vertical direction, and rapid serial visual presentation (RSVP), where words are presented one at a time on a display. However, even with magnification, reading speed in people with central vision loss is still lower than that at the normal fovea. ![]() For instance, in low vision clinics, patients are routinely prescribed with magnifiers for reading tasks. Previous studies have examined a number of ways to improve reading performance in people with central vision loss. Perceptual learning might be an effective way of enhancing visual performance for people with central vision loss. Rather, the improvements are likely to represent genuine plasticity of the visual system despite the older ages of the observers, coupled with long-standing sensory deficits. The specificity of the learning effect, and the lack of changes to the fPRL location and fixation stability suggest that the improvements are not due to observers adopting a retinal location with better visual capability, or an improvement in fixation. Comparisons of pre- and post-test measurements revealed little changes in visual acuity, critical print size, location of the fPRL, and fixation stability. The improvement averaged 53% (range, 34–70%). A post-test, identical with the pre-test, followed the training.Īll observers showed improved RSVP reading speed after training. Training consisted of six weekly sessions of RSVP reading, with 300 sentences presented per session. ![]() A pre-test consisted of measurements of visual acuities, RSVP reading speeds for six print sizes, the location of the preferred retinal locus for fixation (fPRL), and fixation stability. ![]() Six observers (mean age, 73.8) with long-standing central vision loss practiced an oral sentence-reading task, with words presented sequentially using rapid serial visual presentation (RSVP). In this study, the feasibility of applying perceptual learning to enhance reading speed in people with long-standing central vision loss was evaluated. ![]() Perceptual learning has been shown to be effective in improving visual functions in the normal adult visual system, as well as in adults with amblyopia. ![]()
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