Abstract
Individual differences in verbal ability measured by Verbal Scholastic Aptitude Test score and imagery ability measured by Betts' Questionnaire Upon Mental Imagery and Marks' Vividness of Visual Imagery Questionnaire were determined. The latter two were positively correlated, and neither correlated with the Scholastic Aptitude Test. Subjects high in verbal ability and high in imagery independently increased paired-associate recall over those low in verbal ability and imagery when the Marks scale was used as the measure of imagery. Paivio's dual-coding hypothesis was generally supported, and the conceptual-peg function of concrete stimuli was especially beneficial to subjects of low verbal ability and high imagery. The Marks scale was superior to the shortened Betts scale for predicting the effects of ability to image on recall for these 4 groups of 20 subjects each.