Letter-recognition and reading speed in peripheral vision benefit from perceptual learning

Abstract

Visual-span profiles are plots of letter-recognition accuracy as a function of letter position left or right of the midline. Previously, we have shown that contraction of these profiles in peripheral vision can account for slow reading speed in peripheral vision. In this study, we asked two questions: (1) can we modify visual-span profiles through training on letter-recognition, and if so, (2) are these changes accompanied by changes in reading speed? Eighteen normally sighted observers were randomly assigned to one of three groups: training at 10 degrees in the upper visual field, training at 10 degrees in the lower visual field and a no-training control group. We compared observers' characteristics of reading (maximum reading speed and critical print size) and visual-span profiles (peak amplitude and bits of information transmitted) before and after training, and at trained and untrained retinal locations (10 degrees upper and lower visual fields). Reading speeds were measured for six print sizes at each retinal location, using the rapid serial visual presentation paradigm. Visual-span profiles were measured using a trigram letter-recognition task, for a letter size equivalent to 1.4x the critical print size for reading. Training consisted of the repeated measurement of 20 visual-span profiles (over four consecutive days) in either the upper or lower visual field. We also tracked the changes in performance in a sub-group of observers for up to three months following training. We found that the visual-span profiles can be expanded (bits of information transmitted increased by 6 bits) through training with a letter-recognition task, and that there is an accompanying increase (41%) in the maximum reading speed. These improvements transferred, to a large extent, from the trained to an untrained retinal location, and were retained, to a large extent, for at least three months following training. Our results are consistent with the view that the visual span is a bottleneck on reading speed, but a bottleneck that can be increased with practice.

Functional and cortical adaptations to central vision loss

“…† It is possible that the impressive improvement in reading speed in Nilsson et al's study might have been due, at least in part, to training in peripheral reading per se, rather than to the advantage of the TRL location. Chung et al (2004) found a significant but smaller increase in peripheral reading speed among normally sighted participants after training on a letterrecognition task in peripheral vision. Their participants were trained 2 h per day for 4 days, one group at 10 deg above fixation and a second group 10 deg below fixation.…”

Perceptual Learning in Children With Infantile Nystagmus: Effects on Reading Performance

“…17 The 2-fold aim of the present study was to compare baseline reading performance of those children with the age-matched controls with normal vision, and to assess training-induced changes in their reading performance. Our participant group of children with IN consisted of children with idiopathic IN and children with albinism accompanied by IN. Previous studies have demonstrated that reading performance can be improved by perceptual learning, [18][19][20] which refers to a long-term performance increase resulting from perceptual experience. 21 The reading measure that is improved by perceptual learning depends on the paradigm used.…”

Letter Visibility and the Optimal Viewing Position Effect of Isolated Connected and Un-Connected Letters in Arabic

“…Left -to-right-reading adults should be bett er at identifying words within the central or right-to-central part of their visual fi eld because that is where they have adapted to visualize words while learning to read (Chung, Legge, & Cheung, 2004). Yet, there is no clear left ward asymmetry of the OVP eff ect in languages read from right to left , such as Arabic or Hebrew (Farid & Grainger, 1996;Nazir et al, 2004).…”