Even though both binocular rivalry and dichoptic masking are well-studied phenomena, their relationship is not well understood. This lack of knowledge exists because the two tools have, to our knowledge, never been studied with the same set of stimuli in a single comparative study. One other reason is that research questions for the two tools have generally differed. Research on binocular rivalry is mainly focused on the spatial determinants controlling stimulus visibility, finding for example that with increasing orientation and spatial frequency differences the rivalry rate increases between competing interpretations (e.g., Alais & Blake,
2005; Hollins,
1980; O'Shea,
1998; O'Shea, Sims, & Govan,
1997; Schor,
1977). When studied, temporal stimulus modulations in the order of hundreds of milliseconds do not seem to affect binocular rivalry (O'Shea & Blake,
1986; O'Shea & Crassini,
1984; Wolfe,
1983). Dichoptic masking research, on the other hand, is mainly focused on temporal aspects of stimulus visibility, showing, for example, that competition is strong at short stimulus onset asynchronies and decreases with longer asynchronies (e.g., Breitmeyer & Ogmen,
2006; Breitmeyer, Rudd, & Dunn,
1981; Kolers & Rosner,
1960; Macknik, Martinez-Conde, & Haglund,
2000; Michaels & Turvey,
1979; Schiller,
1965; Turvey,
1973). Interestingly, there is a distinct research direction within the dichoptic masking field that does study spatial characteristics of stimulation. This line of research uses spatially and temporally overlapping targets and masks (e.g., Baker, Meese, & Summers,
2007; Legge,
1979; Levi, Harwerth, & Smith,
1979; McKee, Bravo, Taylor, & Legge,
1994; Meese & Hess,
2004) and seems more focused on binocular interactions per se than on object or event perception.