Development and validation of measures of referential activity.

Early research on the referential process (RP) focused on the function of connecting words and the entities to which they refer, as a trait, a dimension on which people differed in a relatively stable manner. The first study found a correspondence between retrieval time for a small set of color names, hand movements accompanying speech, and features of language content and style, such as use of particular pronouns and direct quotes. The second study supported these results using an early version of the Referential Activity (RA) scales, as well as a task of generating labels for subtly differing stimuli where labels had not been provided. Another study provided a close examination of the relation of hand and body movements to the functions of the RP. The current forms of the RA scales, Concreteness, Specificity, Clarity, and Imagery, which serve as the basis for the computerized measures of the Symbolizing function, were developed based on those early studies. Recent research on the RP, some of which will be presented in this issue, has focused primarily on the Symbolizing function as a state rather than trait dimension, and has examined factors affecting variation in this function. The early research also serves as a basis for empirical study of the other functions of the RP. Through interactive development of measures and theory, in experimental and clinical settings, the constructs of the multiple code theory and the RP continue to be refined and redefined.