Abstract
Purpose: :
To investigate the contribution of central and peripheral vision to spatial representations in realistic environments
Methods: :
19 patients with central vision loss (AMD) and 13 controls were included. All patients underwent visual field test, fundus autofluorescence, fluorescein angiography to assess the visual field defect and the lesion size. In a virtual navigation paradigm, observers were first presented with one view of a scene (the prime view), and their task was to navigate through the scene by moving forward or backward in order to match the prime view. To simulate this navigation procedure, a series of consecutive snapshots were constructed from a very close to very far view of the scene. Memory performance was measured as the number steps of between the selected view and the prime view.
Results: :
When navigating to the prime view, both AMD patients and controls showed systematic biases toward the center of the room. AMD patients exhibited a stronger center biases after presentation of close and far prime views and navigated accurately when a middle view was presented. No relation was found between visual acuity, visual field defect, lesion size and the performance of virtual navigation.
Conclusions: :
Navigation tasks through realistic indoor scenes can be accomplished with the low spatial resolution of peripheral vision. Stronger center biases for a scene location suggest that AMD patients rely more on their memory of a "canonical" view. The results may have implications for the development of orientation and mobility rehabilitation in elderly.
Keywords: age-related macular degeneration • space and scene perception