Independence of verbal and visual codes of the same stimuli.

Abstract

This study determines the relation between accuracy of visual recognition of previously exposed object drawings and probability of correct verbal recognition of the object names on a multiple-choice test. The results indicate that performance on the visual and verbal tests is uncorrelated. It is concluded that organizational class characteristics of visual storage do mediate verbal recognition, but that retention of these class characteristics is uncorrelated with retention of the item-specific aspects of visual storage needed for accurate visual recognition. Information presented in visual form is often recoded verbally, and vice versa, and one code may serve to improve retention of the other. Thus, Bower (1970) has shown that visual imagery instructions during learning can improve recall performance of verbal material. Little is known, however, regarding the nature of the interrelations between visual and verbal codes during acquisition and retention. For example, the two codes may be maintained in storage independently, with one acting as a retrieval cue for the other; or the verbal code may be partially or completely lost and verbal retention depend upon receding of certain aspects of visual storage at the time of recall. Visual and verbal memory have frequently been compared, but the data are rarely based upon retention of the same stimuli by the same 5s. In an earlier investigation (Bahrick & Boucher, 1968), probability of free recall of the names of object drawings was found to be independent of the accuracy of subsequent visual recognition of these same drawings. The 5s were as likely to recall the object name of drawings they misidentified by committing large visual recognition errors as of drawings they subsequently correctly identified on a visual recognition test. Despite this lack of correlation of verbal and visual retention performance, it was concluded that 5s used recoded visual storage to aid verbal recall. This interpretation was based on the assumption that recall of a verbal label for visual storage depends only upon the preservation of certain aspects of the visual code and that preservation of these critical aspects may be uncorrelated with the preservation of other aspects necessary for accurate visual recognition. Thus, 5 may be able to recall that he saw a drawing of a cup by retaining a general image of a cup, but retention of this general form may be uncorrelated with retention of other visual details such as the design on the cup or the shape of the handle. An alternative interpretation of the observed independence of the two indicants of retention is based on the fact that the verbal test involved recall while the