Production between and within: distinctiveness and the relative magnitude of the production effect.

The production effect is the memory advantage for items studied aloud over items studied silently. Three experiments examined the influence of (1) the distinctiveness heuristic in a pure-list paradigm and (2) statistical distinctiveness during study. Aloud versus silent processing was manipulated within-subject in a mixed-list procedure and additional pure-list items were alternated with the to-be-remembered words. This arrangement permitted the first examination of the production effect using both within-subject and between-subjects manipulations in the same experiment. The quite large between-subjects production effect observed for the pure-list words is attributed to the distinctiveness of the aloud words being enhanced by the co-occurring within-subject manipulation. In addition, when the pure-list words were all read aloud, they effectively increased the overall proportion of aloud words, thereby decreasing the distinctiveness of the to-be-remembered aloud words in the mixed list. Correspondingly, there was a decrease in the magnitude of the production effect. However, when the pure-list words were all read silently, the magnitude of the production effect was unchanged relative to baseline. These results provide partial support for the influence of statistical distinctiveness on the magnitude of the production effect.