PURPOSE: Persons with central scotomas frequently use a preferred retinal locus (PRL) in place of the damaged fovea to fixate a target. Here the authors use a novel statistical technique to determine whether the retinal locus used for fixating a point target is the same as that used for reading words. METHODS: Nine subjects with established macular disease and bilateral central scotomas were recruited. The retinal area used for fixating a point target and words of text was measured using a microperimeter. A nonparametric spatial statistical technique was used to identify whether fixation points were the same for each of these two tasks. RESULTS: The spatial distribution of fixation points was different for point fixation and word reading in all subjects with macular disease (P<0.01). Fixation stability was also poorer for the word reading task than the fixation task (P<0.05). For control subjects without macular disease, the distribution of fixation was the same for each task (P>0.3). CONCLUSIONS: Fixation behavior in persons with macular disease is not the same for fixating a point target and for fixating words in a reading task. It cannot be assumed that measuring a patient's fixation to a discrete point target accurately simulates their fixation performance on other tasks.
PURPOSE:Persons with central scotomas frequently use a preferred retinal locus (PRL) in place of the damaged fovea to fixate a target. Here the authors use a novel statistical technique to determine whether the retinal locus used for fixating a point target is the same as that used for reading words. METHODS: Nine subjects with established macular disease and bilateral central scotomas were recruited. The retinal area used for fixating a point target and words of text was measured using a microperimeter. A nonparametric spatial statistical technique was used to identify whether fixation points were the same for each of these two tasks. RESULTS: The spatial distribution of fixation points was different for point fixation and word reading in all subjects with macular disease (P<0.01). Fixation stability was also poorer for the word reading task than the fixation task (P<0.05). For control subjects without macular disease, the distribution of fixation was the same for each task (P>0.3). CONCLUSIONS: Fixation behavior in persons with macular disease is not the same for fixating a point target and for fixating words in a reading task. It cannot be assumed that measuring a patient's fixation to a discrete point target accurately simulates their fixation performance on other tasks.
Authors: Faran Sabeti; Jo Lane; Emilie M F Rohan; Bhim B Rai; Rohan W Essex; Elinor McKone; Ted Maddess Journal: Transl Vis Sci Technol Date: 2021-02-05 Impact factor: 3.283
Authors: Richard A I Bethlehem; Serge O Dumoulin; Edwin S Dalmaijer; Miranda Smit; Tos T J M Berendschot; Tanja C W Nijboer; Stefan Van der Stigchel Journal: PLoS One Date: 2014-06-17 Impact factor: 3.240