Déruaz A, Whatham A R, Mermoud C, Safran A B
Neuro-Ophthalmology Unit, Clinic of Ophthalmology, Department of Clinical Neurosciences and Dermatology, Geneva University Hospitals, Geneva, Switzerland.
Vision Res. 2002 Dec;42(27):2947-57. doi: 10.1016/s0042-6989(02)00354-1.
The reading strategies in individuals with central scotomas and more than one preferred retinal locus (PRL) were investigated using a scanning laser ophthalmoscope in order to understand the visual requirements that lead to the need to use more than one PRL during reading. It was found that: (1) PRL function can be deduced from variation in PRL usage for different size and length of isolated words; (2) each subject used two or more PRL to accomplish the functions of global viewing and discrimination, suggesting that these are two of the minimum requirements for reading; (3) reading strategies can change depending on the position of words in visual space; (4) line-changing strategies can revert to horizontal and vertical component movements. These findings have implications for improving reading performance through training in patients with central scotomas.
