The Category-Order Effect in Supraspan Recall

The category-order effect is observed when stimuli from a small, homogenous category are presented before a large, heterogeneous category (Greene & Lasek, 1994). Schoenherr and Thomson (2008) determined that the category-order effect was a product of the phonotactic properties of the category, facilitating recall in situations that were not consistent with Greene and Lasek’s account. In the present study, we examine recall once word length and word frequency effects were controlled in exemplar (e.g., bird, hawk) or feature (e.g., claw, wing) lists. We then compared recall performance when words either preceded or followed single-digit number stimuli. To control for the effect of presentation format, number stimuli were presented as single-digits or words. Although our findings support a category-order effect, they challenge the definition offered by early research. Specifically, orthographic properties and word frequency influenced the category-order effect, suggesting that it is not simply a result of category size and homogeneity.