Abstract
While the amount of literature showing effects of interocular grouping in binocular rivalry is growing, relatively little is said about the integration of suppressed and visible information. Using the dichoptic suppression paradigm (Van Lier & De Weert, 2003) we demonstrate that the visibility of suppressed elements is influenced by similarity in orientation of the suppressed elements and an additional trigger element. This effect is irrespective of whether the suppressed elements and the trigger element are presented in the same eye or not. In dichoptic suppression, each element is suppressed by presenting a neutral high contrast element (i.e., suppressor) at the same location in the contra-lateral eye. In our experiment, we suppressed two gratings presented left and right of fixation (i.e., the flanking gratings); the gratings were either horizontally or vertically oriented. After suppression (600 msec) the suppressors were removed. Next, a grating was presented in the centre (i.e., the trigger grating), which' orientation was the same as the orientation of one of the suppressed gratings. This grating was presented in only one eye. Subsequently, participants had to indicate which of the suppressed gratings became visible first. Overall, gratings with the same orientation as the trigger grating became visible earlier than gratings with a different orientation. The effect of orientation was significant when the trigger grating was presented in the same eye as the flanking gratings (p [[lt]] .001), as well as when the trigger grating was presented in the contra-lateral eye (p [[lt]] .01). In a control experiment we demonstrate that this effect of orientation is not simply triggered by the collinearity of the gratings. Our results show that the activation of suppressed elements is influenced by their similarity with already visible elements.
MV is supported by a grant of NWO