This book has several ambitious aims and these are both theoretical and practical. On a practical level the book oers a selective but wide-ranging review of the literature on both visual imagery and working memory. It starts from a fairly basic level and discusses each of the issues thoroughly. Unusually, the book takes little for granted. For example, it starts by reviewing the evidence that there is a temporary storage function in memory in the ®rst place, let alone a temporary visuo-spatial memory system. Contrary evidence is also discussed to give a refreshingly balanced view and this is all achieved using a clear and informative writing style. In this way the book provides an insightful and engaging historical account of the research carried out on visuo-spatial processing. On a more theoretical level, it is argued that visuospatial processing plays a central role in many human activities ranging from memory, perception and navigation through to planning, thinking and problem solving. Fundamentally, the book aims to come up with a coherent account of how the visual and spatial cognitive operations involved in these tasks are organized in terms of a temporary working memory system. To achieve this aim, Logie compares and contrasts the parallel approaches of both working memory and imagery and also takes into account a wide range of other evidence, especially from the neuropsychological literature. Until recently, there has been considerably less research on visuo-spatial memory than on other areas of working memory but this book re¯ects the fact that this imbalance is in the process of being corrected. Indeed, the author is himself a major contributor to this process.
Although evidence is also discussed from other theoretical perspectives, notably from the literature on neuropsychology and imagery, undoubtedly it is the working memory model of Baddeley and Hitch (1974) that forms the main theoretical framework of this book. Although Logie's book comes over twenty years after the working memory model was originally proposed, the working memory paradigm still remains an important and in¯uential approach to the investigation of the organization of short-term memory. The working memory model is a multi-component model of memory with a limited capacity central executive responsible for attentional processes and with temporary storage occurring in a number of subsidiary systems. Although the visuo-spatial sketchpad (VSSP) part of the model was initially proposed as the subsidiary system that maintains and manipulates visual material, until relatively recently considerably less was known of this part of the model.
A major aim in this book is clearly focused on identifying the key components of visuo-spatial working memory by concentrating on the role that memory and attentional processes play in storing and manipulating both visual and spatial information. To this end, Chapter 2 is devoted to a review of the literature investigating the phenomenon of imagery. Although it is also concerned with looking at the relationship of imagery and perception and how the mechanisms that let us produce, maintain, interpret and transform visual mental images might dier from those of perception, the chapter also aims to relate and contrast the imagery literature with that of visuo-spatial working memory. In a similar vein, Chapter 3 focuses on the range of tasks that a visuo-spatial working memory should probably be involved in. Chapter 4 is a particularly key chapter that aims to unravel the relationship that this temporary visuo-spatial memory system might have with the rest of working memory, particularly the central executive. This chapter gives a thorough review of the working memory model and presents evidence that visual and spatial information are handled separately by working memory. This evidence is critical for Logie's own particular view of visuo-spatial working memory that is presented in the last