Mental comparisons for ordered information on abstract and concrete dimensions

Subjects compared pairs of animal, country, and car names, which had been ranked along concrete (perceptual) and abstract (nonperceptual) dimensions by an independent group (e.g., animals were rated for size and ferocity). For judgments based on abstract and concrete dimensions, comparison time decreased as the difference between the rated scale values of the items increased. Furthermore, comparison time was better predicted by the interval than by the ordinal distance between test pairs. This finding suggests that judgments are based on some kind of long-term memory representation which has analog characteristics, in that it preserves more than rank-order information. The question of whether one common memory code or two separate codes are involved in comparisons based on abstract and concrete dimensions is discussed. Three alternative models are proposed and the role of visual imagery in memorial comparisons is considered.