Distinguishing Imaginal and Verbal Mediators
The evidence reviewed in the last two chapters demonstrated clearly that imaginal-and verbal-mediation procedures can influence learning and memory, but the inferred mediating processes were not theoretically distinguished. The many similarities in the effects of the different procedures in fact lead us to question the necessity of postulating two classes of mediators. It becomes compelling to do so only if differential effects can be demonstrated as a function of variation in the empirical operations that define the two theoretical concepts. Toward that end, the present chapter focuses on evidence derived from studies in which imaginal and verbal mediators have been directly compared.