The effects of temporal synchrony on the perceived organization of elements in spatially symmetric and asymmetric grids

Three experiments were conducted to investigate the influence of fast tempo rally segmented presentations of alternate rows or columns on the perceptio n of grids of either symmetrically or asymmetrically spaced dot-like stimul i. Experiments 1a and 1b demonstrated that observers were able to discrimin ate between temporally segmented presentations of rows/columns stimuli, but showed a reduced performance in discrimination between non-temporally segm ented stimuli and temporally segmented stimuli that were spatially unstruct ured. Experiment 2 confirmed the influence of temporally segmented presenta tions of rows and columns using elements whose mean luminance summed to the same as the display background. Experiment 3 demonstrated that the influen ce of temporal cues reduced when display elements were asymmetrically space d. The results are discussed in terms of the influence of external spatio-t emporal factors on the neural mechanisms of visual grouping.