ABSTRACT
Visual perception of a target element can be strongly modulated by contextual elements surrounding the target. In a companion poster it is shown that collinear elements can exert strong suppression—in contradiction to all studies on contextual modulation— that show contextual facilitation of contextual collinear elements in accordance with the Gestalt law of good continuation. Except for offset, all spatial parameters of grating elements were the same as those of the foregoing vernier. Segments were 600” long and separated by a small vertical gap of 60”. Horizontal spacing between grating elements was 200”. The grating and the contextual elements were always presented simultaneously. Vernier, grating and contextual gratings could be presented to the left or right eye each separately, eg the vernier could be presented to the right eye and the grating accompanied by contextual elements to the left eye. This dichoptic presentation was achieved by using two analog monitors equipped with polarizing filters and matching goggles.
