VISUAL-ATTENTION AND OBJECTS - NEW TESTS OF 2-OBJECT COST

Baylis and Driver (1993) proposed that the positions of object parts a re coded relative to the position of the object they belong to and tha t parts of different objects are not directly coded relative to each o ther. This theory predicts that it is easier to judge a difference in height of parts belonging to a single object (one-object condition) th an of parts belonging to two objects (two-object condition). This two- object cost has been reported in several articles (Baylis, 1994; Bayli s & Driver, 1993, 1995). However, in all these experiments, the method that was used favored the one-object condition. In the present experi ments we obtained, for the first time, evidence for the existence of t wo-object cost without such a bias.