Our ability to be conscious of the world around us is often discussed as one of the most amazing yet enigmatic processes under scientific investigation today. However, our ability to imagine the world around us in the absence of stimulation from that world is perhaps even more amazing. This capacity to experience objects or scenarios through imagination, that do not necessarily exist in the world, is perhaps one of the fundamental abilities that allows us successfully to think about, plan, run a dress rehearsal of future events, re-analyze past events and even simulate or fantasize abstract events that may never happen. Empirical research into mental imagery has seen a recent surge, due partly to the development of new neuroscientifc methods and their clever application, but also due to the increasing discovery and application of more objective methods to investigate this inherently internal and private process. As the topic is cross hosted in Frontiers in Perception Science and Frontiers in Human Neuroscience, we invite researchers from different fields to submit opinionated but balanced reviews, new empirical, theoretical, philosophical or technical papers covering any aspect of mental imagery. In particular, we encourage submissions focusing on different sensory modalities, such as olfaction, audition somatosensory etc. Similarly, we support submissions focusing on the relationship between mental imagery and other neural and cognitive functions or disorders such as visual working memory, visual search or disorders of anxiety. Together, we hope that collecting a group of papers on this research topic will help to unify theory while providing an overview of the state of the field, where it is heading, and how mental imagery relates to other cognitive and sensory functions.

When we try to remember whether we left a window open or closed, do we actually see the window in our mind? If we do, does this mental image play a role in how we think? For almost a century, scientists have debated whether mental images play a functional role in cognition. In The Case for Mental Imagery, Stephen Kosslyn, William Thompson, and Giorgio Ganis present a complete and unified argument that mental images do depict information, and that these depictions do play a functional role in human cognition. They outline a specific theory of how depictive representations are used in information processing, and show how these representations arise from neural processes. To support this theory, they seamlessly weave together conceptual analyses and the many varied empirical findings from cognitive psychology and neuroscience. In doing so, they present the conceptual grounds for positing this type of internal representation and summarize and refute arguments to the contrary. Their argument also serves as a historical review of the imagery debate from its earliest inception to its most recent phases, and provides ample evidence that significant progress has been made in our understanding of mental imagery. In illustrating how scientists think about one of the most difficult problems in psychology and neuroscience, this book goes beyond the debate to explore the nature of cognition and to draw out implications for the study of consciousness. Student and professional researchers in vision science, cognitive psychology, philosophy, and neuroscience will find The Case for Mental Imagery to be an invaluable resource for understanding not only the imagery debate, but also and more broadly, the nature of thought, and how theory and research shape the evolution of scientific debates.

This book represents the research efforts of individuals whose scientific expertise lies in reflection on what Sartre described as reflective acts. Theory in the cognitive psychology of mental imagery, endeavors not only being able to describe the contents and nature of mental imagery, but also being able to understand the underlying functional cognition. Psychologists need not solely rely on the techniques of introspection, and the last two decades have seen highly creative developments in techniques for eliciting behavioural data to be complemented by introspective reports. This level of sophistication has provided singular insights into the relationship between imagery and other consequential and universal aspects of human cognition: perception, memory, verbal processes and problem solving. The recognition that imagery, despite its ubiquitous nature, differs between individuals both in prevalence and in kind, and the dramatic rise in cognitive science has provided the additional potential for integrating our understanding of cognitive function with our understanding of neuroanatomy and of computer science. All of these relationships, developments and issues are dealt with in detail in this book, by some of the most distinguished authors in imagery research, working at present in both Europe and the USA.

Kosslyn makes an impressive case for the view that images are critically involved in the life of the mind. In a series of ingenious experiments, he provides hard evidence that people can construct elaborate mental images, search them for specific information, and perform such other internal operations as mental rotation.

The locus of concreteness effects in memory for verbal materials has been described here in terms of the processing of shared and distinctive information. This theoretical view is consistent with a variety of findings previously taken as support for dual coding, insofar as both verbal and perceptual information may be involved in comprehending high-imagery sentences and in learning lists of concrete words. But going beyond previous accounts of imagery, this view also can provide explanations for several findings that appear contradictory to the thesis that concrete and abstract materials differ in the form of their storage in long-term memory. Although this does not rule out a role for imagery in list learning or text comprehension, it is clear that the complex processes involved in comprehension and memory for language go beyond mechanisms supplied by a theory based on the availability of modality-specific mental representations. The task now is to determine the viability of the theory in other domains. Several domains of imagery research presented at EWIC provided fertile ground for evaluating my theoretical viewpoint. Although not all provide a basis for distinguishing representational theories of imagery from the imagery as process view, there are data in several areas that are more consistent with the latter than the former. In other cases, there are at least potential sources of evidence that would allow such a distinction.