This work presents a systematic analysis of the psychological phenomena associated with the concept of mental representations—also referred to as cognitive or internal representations. A major restatement of a theory the author first developed in his 1971 book (Imagery and Verbal Processes), Mental Representation covers phenomena from the earlier period that remain relevant today but emphasizes cognitive problems and paradigms that have since emerged more fully. The author proposes that performance in memory and other cognitive tasks is mediated not only by linguistic processes but also by a distinct nonverbal imagery model of thought as well. He discusses the philosophy of science associated with the dual coding approach, emphasizing the advantages of empiricism in the study of cognitive phenomena and showing that the fundamentals of the theory have stood up well to empirical challenges over the years. An important contribution to the understanding of form and function of human knowledge, this book will be of interest to students and researchers in cognitive psychology, cognitive science, linguistics, and philosophy.