Reading word “airplane” is seeing object “airplane” in the right cerebral hemisphere: The effect of object contour diagnosticity on within-modal and cross-modal priming

Abstract

Within-modal priming (e.g., naming picture “bus” primes naming picture “bus”, P-P priming) is always found to be substantially larger than cross-modal priming (e.g., reading word “bus” primes naming picture “bus”, W-P priming). In the present study, we manipulated “global diagnosticity” of object contour to examined whether P-P priming is always larger than W-P priming. We found P-P priming is equivalent to W-P priming on “globally diagnostic” (GD) objects, but the P-P priming is still larger than W-P priming on “globally non-diagnostic“ (GN) objects. This phenomenon appeared on both picture-naming (Experiment 1) and perceptual-identification (Experiment 2) tasks. Better explicit (conscious) memory performance (recognition memory) in P-P condition than that in W-P condition showed that equivalent priming across P-P and W-P conditions on GD objects was dissociated from the influence of conscious recognition memory. Experiment 3 found equivalent P-P priming and W-P priming appeared only when GD objects in the test phase were presented to the right cerebral hemisphere (in the left visual field). These results suggest that reading names of globally diagnostic objects can access the representation or essential features of globally diagnostic objects, and right cerebral hemisphere might be responsible for the processing.