Target difficulty, priority assignment of attentional resources, foveal task load, and order of testing of foveal loading on visual lobe shape characteristics.

Effects of the difficulty of a peripheral target, the priority assignment of attentional resources for simultaneous peripheral and foveal tasks, and the foveal task load and order of testing of cognitive foveal loadings on visual lobe shape characteristics were investigated. Analysis showed that lobe shape characteristics were affected by target difficulty but not the low foveal load. For the tasks used here, attentional resources were sufficient for participants to perform both peripheral and foveal tasks concurrently; therefore, priority assignment of attentional resources had no effect on lobe shape. With regard to order of testing of foveal loading, lobe roundness, boundary smoothness, and vertical symmetry improved with a positive practice effect for the groups tested in the high level-low level order. The implication is that providing training or practice to participants on a task with a higher level foveal load could optimize lobe roundness, boundary smoothness, and symmetry. Performance on the foveal task was better with easy peripheral targets than difficult targets and better for the foveal-primary than for the peripheral-primary conditions, presumably because of the larger proportion of attentional resources allocated to the foveal task for these two groups.