Abstract
Sustained attention enhances perception of stimulus located at eccentric positions of the visual field. Perception is not equal for all eccentric directions, leading to topographic variations in attentional performance. Topographic variations found in normally sighted subjects are also valid after acquiring a macular scotoma. The chosen location of the preferred retinal locus of fixation (PRL) can be influenced by these topographic variations. In this study, the relation between the topographic sustained attention and the location of the developed PRL was investigated. Thirteen normally sighted subjects participated in the study. The sustained attention was measured in eccentric locations of the visual field using Manfred Mackeben's paradigm (1999) and fixations were controlled using an eye tracker. Consequently, a 6° macular scotoma was simulated and PRL training was performed in a set of visual tasks during two one-hour sessions. The sustained attention measurement and the two simulations of macular scotoma were separated by at least 24 hours. Polar diagrams with the variations of the sustained attention in eight different directions showed that 77% of the subjects have a stronger attention performance in the horizontal meridian. Furthermore, after two hours of training, subjects developed a PRL. Finally, in five out of thirteen subjects, the directions with good attentional capabilities were candidates for the development of a PRL.
Meeting abstract presented at VSS 2016