Reading with simulated scotomas: attending to the right is better than attending to the left

Abstract

Persons with central field loss must learn to read using eccentric retina. To do this, most adopt a preferred retinal locus (PRL), which substitutes for the fovea. Patients who have central field loss due to age-related macular degeneration (AMD), most often adopt PRL adjacent to and to the left of their scotoma in visual field space. It has been hypothesized that this arrangement of PRL and scotoma would benefit reading. We tested this hypothesis by asking normally-sighted subjects to read with the left or right half of their visual field plus 3.2 degrees in the contralateral field masked from view. Letter identification, word identification, and reading were all slower when only the information in the left visual field was available. This was primarily due to the number of saccades required to successfully read to stimuli. These data imply that patients would be better off with PRL to the right of their scotoma than to the left for the purposes of reading.

Functional and cortical adaptations to central vision loss

“…The average maximum reading speeds were 124 wpm for the lower-/upperfield PRL group and 105 wpm for the other PRL groups. The reason for the discrepancy between Fletcher et al's study on patients with low vision, and the TRL (Nilsson et al, 1998(Nilsson et al, , 2003 and normal peripheral reading studies (Fine & Rubin, 1999;Petre et al, 2000) is yet to be determined. While either a lower-or upper-field PRL may be advantageous in English reading, a visual field loss below the PRL (i.e.…”

“…A simulated scotoma study by Fine and Rubin (1999) also showed that reading performance was best when the simulated scotoma forced their normally sighted participants to read with the lower visual field. Petre et al (2000) also found that peripheral reading speed was faster in † It should be noted that the untrained reading speeds of about 10 wpm in the Nilsson et al (2003) study were lower than those reported in other AMD studies (e.g.…”

Clinical and Microperimetric Predictors of Reading Speed in Low Vision Patients: A Structural Equation Modeling Approach

“…In secondary analyses, we found that having an absolute scotoma right of fixation reduces RS compared with other locations, which was an inconsistent finding in previous research. 9,29 The large sample size and the quantitative approach used could have contributed to this result.…”

Parafoveal processing in reading

“…Rayner and Bertera (1979;see also Fine & Rubin, 1999a, 1999cRayner, Inhoff, Morrison, Slowiaczek, & Bertera, 1981) used a variation of the moving-window paradigm, the moving-mask paradigm (see Fig. 5), to mask foveal letters while retaining the letters in the parafovea and periphery.…”