Spatial comprehension and comparison processes in verification tasks.

Two experiments use the sentence-picture verification paradigm to study encoding and comparison processes with spatial information. Subjects decided whether a spatial description of a figure or a geometric figure matched a second figure. Three critical results (the effects of display complexity, the effects of lexical markedness, and the relative speeds of “same” and “different” responses) covaried across four experimental conditions. These results demonstrate that task-specific variables can be the primary determinants of how subjects verify sentences. When the two displays were presented successively and subjects took as much time as they needed to prepare for the test figure, verification time was not affected by the pictorial complexity of the test figure or by the markedness of the relational terms used in the descriptions, and “same” responses were faster than “different” responses. When subjects had less time to study the spatial description before the test picture appeared, the effects of complexity and lexical markedness on verification time increased and were largest when the two displays appeared simultaneously; concurrently, “differents” became faster than “sames.” This pattern of results is not easily handled hy current models for sentence-picture verification.