A visual imagery task is presented which is beyond the limits of normal human ability, and some of the factors contributing to its difficulty are isolated by comparing the difficulty of related tasks. It is argued that complex objects are assigned hierarchical structural descriptions by being parsed into parts, each of which has its own local system of significant directions. Two quite different schemas for a wire‐frame cube are used to illustrate this theory, and some striking perceptual differences to which (...) they give rise are described. The difficulty of certain mental imagery tasks is shown to depend on which of the alternative structural descriptions of an object is used, and this is interpreted as evidence that structural descriptions are an important component of mental images. Finally, it is argued that analog transformations like mental folding involve changing the values of continuous variables in a structural description. (shrink)

Drawing on his own experiences of imagining, Edward S. Casey describes the essential forms that imagination assumes in everyday life. In a detailed analysis of the fundamental features of all imaginative experience, Casey shows imagining to be eidetically distinct from perceiving and defines it as a radically autonomous act, involving a characteristic freedom of mind. A new preface places Imagining within the context of current issues in philosophy and psychology.

The book also introduces a host of new experimental techniques and major hypotheses to guide future research.

This book collects some of the most exciting pioneering work in perceptual and cognitive psychology. The authors' quantitative approach to the study of mental images and their representation is clearly depicted in this invaluable volume of research which presents, interprets, evaluates, and extends their work. The selections are preceded by a thorough review of the history of their experiments, and all of the articles have been updated with reviews of the current literature. The book's first part focuses on mental rotation; (...) the second includes other, more complex transformations and sequences of transformations. A third part describes work on rotational transformations in the context of the perceptual illusion of &"apparent motion.&" Roger N. Shepard is Professor of Psychology, Stanford University. Lynn A. Cooper is Professor of Psychology, University of Arizona. A Bradford Book. (shrink)

Much of the progress in the fields constituting cognitive science has been based upon the use of explicit information processing models, almost exclusively patterned after conventional serial computers. An extension of these ideas to massively parallel, connectionist models appears to offer a number of advantages. After a preliminary discussion, this paper introduces a general connectionist model and considers how it might be used in cognitive science. Among the issues addressed are: stability and noise‐sensitivity, distributed decision‐making, time and sequence problems, and (...) the representation of complex concepts. (shrink)