PRIMING IMPOSSIBLE FIGURES IN THE OBJECT DECISION TEST - THE CRITICALIMPORTANCE OF PERCEIVED STIMULUS COMPLEXITY

Previous research showed that object decision priming was found for po ssible, but not impossible, three-dimensional objects (e.g., Schacter, Cooper, & Delaney, 1990; Schacter, Cooper, Delaney, Peterson, & Thara n, 1991). We tested those objects and found that the impossible object s were subjectively more complex than the possible objects. We then co nstructed two sets of possible and im possible objects - one set that was equated for complexity, and one set that differed - for use in the object decision test. The results showed that when impossible objects were high in complexity and possible objects were low in complexity, priming was found only for possible objects; when possible and impossi ble objects were equated at a moderate level of complexity, priming wa s observed for both object types. These findings indicate that perceiv ed object complexity, more than object possibility-impossibility, dete rmined priming in the object decision test. The demonstration of objec t decision priming for possible and impossible objects calls for a ref ormulation of the structural description system explanation.