The spatial layout of visual displays was evaluated by means of three magnitude estimation tasks and one reproduction task. Each stimulus display consisted of 16 randomly-drawn, two-digit numbers. Six different spatial layouts, or display types, were used: systematic vs. random spatial order of numbers; regular vs. irregular boundaries of the…

Visual acuity as a function of target position and density was measured in a letter recognition task. A homogeneous pattern of equally-spaced elements was tachistoscopically exposed, where the target was never located at the boundaries of the pattern. The target was marked with a spatial cue to control attentional processes. With such a spatial…