(p. v) The measurement of eye movements as an experimental method in the field of psychology is increasing at an exponential rate. For example, thirty years ago it was possible to count the number of eye movement laboratories in Psychology Departments in the UK on the fingers of one (or maybe two) hands. Today, the majority of Psychology Departments have some form of eye tracking device that is used in research. Indeed, there are many such devices in research departments associated with disciplines other than psychology (e.g., Computer Science, Engineering, etc). It is fair to say that eye movement methodology is now firmly established as a core tool in the experimentalist’s armoury. To those who conduct eye movement research, this exponential growth is not at all surprising given the very tight relationship between eye movements and many aspects of human cognitive processing. This is most obvious when considering complex visual cognitive processes (e.g., reading, problem solving etc.) in which higher order, abstract mental representations directly influence oculomotor behaviour. More recently, however, researchers have started to establish that eye movements are vital for, and informative of, a much greater breadth of human psychological processes (e.g. shared social attention, interpersonal communication, etc.). In addition the eyes have a simple, well-defined repertoire of movements controlled by oculomotor neurons inside the cranium that are accessible to electrophysiological techniques. By recording from these and other neurons in alert animals, it has been possible to reveal many of the details of the motor and premotor circuitry that controls eye movements. This has resulted in a considerable understanding of motor control in general and in the pathophysiology of many visual and eye movement disorders. The saccadic circuitry is now understood at a level that allows us to investigate the neural basis of higher cognitive processes, including target selection, working memory, and response suppression. Without question, the field continues to expand, and this expansion has occurred as a consequence of how useful the methodology has been in furthering research, and how measurement techniques have improved and become simpler to use.
This rapid expansion in the field of eye movement research has two distinct consequences. First, researchers who haven’t previously recorded eye movements as part of their research are increasingly doing so, and second it is becoming increasingly difficult for established researchers in the area to keep abreast of progress or discoveries in other areas of eye movement research. As a result of these perceived needs we felt it was timely to produce a handbook comprised of chapters by experts that are representative of the main areas of research in the field. The current volume, the Oxford Handbook on Eye Movements, is the product of that decision. When we set out to produce the Handbook, we had a clear set of objectives in mind. It needed to provide wide-ranging coverage, coverage that is representative of the breadth of the field at the moment. The chapters needed to be written by leading experts in the field. The content of the chapters needed to be up to date and informative both to other experts working in different areas of the field, and to advanced undergraduate and postgraduate students with an interest in eye movements. In summary, the Handbook needed to represent a snapshot of the current state of the field, a cross section of the work that is currently underway in the eye movement community.
(p. vi) In contributing a chapter, authors were tasked with providing a concise, to the point, high quality review of one or more particular issues that are currently of theoretical significance. All of the chapters were peer reviewed and thorough revisions were carried out on the basis of the reviews. The result, in our view, is a series of pieces of high quality writing delivered by individuals who maintain a very high profile in the field. The Handbook is a blend of both methodologically motivated content and theoretical analysis. The Handbook represents a significant, broad based, theoretical volume comprised of individual chapters focused on research that shares a common methodology.
The Handbook is structured around seven broad themes. In Part 1, we have two chapters offering overviews of eye movements in different species and of the history of eye movement research and five chapters that introduce different types of eye movements. Part 2 delivers a series of 14 chapters in which the anatomy and neural mechanisms underlying oculomotor control are discussed in detail. Part 3 contains six chapters detailing the relationship between eye movements and attention, and in Part 4 there are seven chapters that consider eye movements in relation to visual cognitive processing. In Part 5, five chapters cover aspects of development and pathology, and eye movements in special populations. In Parts 6 and 7 (eight and seven chapters respectively), the topic of reading is addressed, with Part 6 covering issues of oculomotor control in relation to reading, and the latter dealing with eye movements and their relationship to issues associated with linguistic processing. In total, the Handbook contains 54 Chapters that deliver a comprehensive coverage of the field. Inevitably there are areas of research which we have not included. In most cases this was to avoid producing a handbook that was simply too big. One example would be the limited coverage of eye movement research in an applied context (e.g., sports, engineering, ergonomics). The other obvious omission is the exclusion of a broad coverage of the neurology of eye movements.
Producing a volume of this magnitude would not be possible without the support of a dedicated team. The Editors are extremely grateful to Gwen Gordon who provided a tremendous amount of editorial assistance throughout. We would also like to thank Pippa Smith and Kathryn Smith who also assisted with editorial duties. The team at Oxford University Press have provided excellent support from the very beginning to the end of this project, and we are extremely grateful for their help and patience. Particularly, we would like to thank Martin Baum, Charlotte Green, Carol Maxwell and Priya Sagayaraj. We are also very grateful to Gerry Altmann who came up with the word cloud design for the front cover. We would also like to thank all the contributors to the volume – without them the Handbook would not have been possible. When we initially approached potential contributors to the volume, we were curious to see what the uptake to our invitation would be – to what extent would colleagues in the field not only be responsive to our request to contribute, but also take their task earnestly? It was a great pleasure to us that we had an overwhelmingly positive response to our invitation, and we were delighted that all of the authors delivered such high quality chapters. We are also grateful to the authors for taking the peer review process seriously both by acting as reviewers and responding carefully and diligently to the reviews of their own work. We know that this process has contributed significantly to the quality of the finalised chapters. Again, we are very grateful to the authors for making the effort to write such good chapters. Finally, it is likely that we have managed to forget to thank a number of people who have helped along the way, and to those people, we apologise.
In summary, we believe that together we have produced an Oxford Handbook on Eye Movements that is a high quality comprehensive volume. We anticipate that it will be used as a text by undergraduate and postgraduate students, and eye movement researchers alike to obtain synopses of specific topics currently under investigation in the eye movement community. We hope that you enjoy reading it.
Simon P. Liversedge
Iain D. Gilchrist