Originally published in 1981, this third volume deals with the empirical data base and the theories concerning visual perception the set of mental responses to photic stimulation of the eyes. As the book develops, the plan was to present a general taxonomy of visual processes and phenomena. It was hoped that such a general perspective would help to bring some order to the extensive, but largely unorganized, research literature dealing with our immediate perceptual responses to visual stimuli at the time. The specific goal of this work was to provide a classification system that integrates and systematizes the data base of perceptual psychology into a comprehensive intellectual scheme by means of an eclectic, multi-level "metatheory" invoking several different kinds of explanation."
Originally published in 1981, this third volume deals with the empirical data base and the theories concerning visual perception – the set of mental responses to photic stimulation of the eyes. As the book develops, the plan was to present a general taxonomy of visual processes and phenomena. It was hoped that such a general perspective would help to bring some order to the extensive, but largely unorganized, research literature dealing with our immediate perceptual responses to visual stimuli at the time. The specific goal of this work was to provide a classification system that integrates and systematizes the data base of perceptual psychology into a comprehensive intellectual scheme by means of an eclectic, multi-level metatheory invoking several different kinds of explanation.
This report summarizes the contents of a book entitled The Processes of Visual Perception written during the course of this contract. The book presents a classification system of visual processes that organizes and arranges the extensive data base of perceptual science. The taxonomy consists of 6 levels: Level 0, Preneural Transformations; Level 1, Receptor Transformations; Level 2, Neural Network Transformations; Level 3, Figural Organization Processes; Level 4, Multidimensional Interactions; and Level 5 Image Manipulation. (Level 5 is not discussed in this book. It will be the topic of the next book in the series of which this present one is the third volume.) This progress report presents a brief summary of each of the chapters in the book as well as the entire last chapter. This final epilog, entitled 'Emerging Principles of Visual Perception' was the target towards which this entire research project was aimed. At the outset of the book, it was asserted that the major contribution it could make would be the statement of current thinking in the field of perceptual science. This list of principles, as well as the taxonomy itself, is a synthetic and integrative metatheory of perceptual processing as our science sees it in the last third of the twentieth century. (Author).
Recent vision research has led to the emergence of new techniques that offer exciting potential for a more complete assessment of vision in clinical, industrial, and military settings. Emergent Techniques for Assessment of Visual Performance examines four areas of vision testing that offer potential for improved assessment of visual capability including: contrast sensitivity function, dark-focus of accommodation, dynamic visual acuity and dynamic depth tracking, and ambient and focal vision. In contrast to studies of accepted practices, this report focuses on emerging techniques that could help determine whether people have the vision necessary to do their jobs. In addition to examining some of these emerging techniques, the report identifies their usefulness in predicting performance on other visual and visual-motor tasks, and makes recommendations for future research. Emergent Techniques for Assessment of Visual Performance provides summary recommendations for research that will have significant value and policy implications for the next 5 to 10 years. The content and conclusions of this report can serve as a useful resource for those responsible for screening industrial and military visual function.
In the mid-sixties, John Robson and Christina Enroth-Cugell, without realizing what they were doing, set off a virtual revolution in the study of the visual system. They were trying to apply the methods of linear systems analysis (which were already being used to describe the optics of the eye and the psychophysical performance of the human visual system) to the properties of retinal ganglion cells in the cat. Their idea was to stimulate the retina with patterns of stripes and to look at the way that the signals from the center and the antagonistic surround of the respective field of each ganglion cell (first described by Stephen Kuffier) interact to generate the cell's responses. Many of the ganglion cells behaved themselves very nicely and John and Christina got into the habit (they now say) of calling them I (interesting) cells. However. to their annoyance, the majority of neurons they recorded had nasty, nonlinear properties that couldn't be predicted on the basis of simple summ4tion of light within the center and the surround. These uncoop erative ganglion cells, which Enroth-Cugell and Robson at first called D (dull) cells, produced transient bursts of impulses every time the distribution of light falling on the receptive field was changed, even if the total light flux was unaltered.
Visual control of our actions can be unconscious as well as conscious. For example, when a pedestrian steps onto a street and then suddenly steps back, to avoid being hit by an oncoming car, the pedestrian's visual system has been able to detect the car very rapidly. Since the registration of the approaching car in conscious vision could take a few hundreds of milliseconds - possibly too long to avoid being struck by it, the rapid injury-avoiding action has relied on the oncoming car being detected at unconscious levels in the visual system. So how, and at what level in the visual system is a stimulus processed unconsciously? This book explores unconscious and conscious vision, investigated using psychophysical and brain-recording methods. These methods allow microtemporal analyses of visual processing during the interval, ranging from a few 10s to a few 100s of milliseconds, between a stimulus's impinging on the retinae and its eliciting a behavioral response or a conscious percept. By tying these findings to well-known neuroanatomical and physiological substrates of vision, the book presents and discusses theoretical and empirical approaches to, and findings on, conscious and unconscious vision. In addition to presenting an in-depth, integrative review of recent and ongoing scientific and scholarly research, the book proposes several avenues for directing future research in these areas. It also provides a well articulated theoretical and a detailed empirical base that points to the special importance of the processing of surface properties of visual objects to their conscious vision. Aimed at scientists and scholars in visual cognition, visual neuroscience and, more broadly, cognitive science - including that part of the philosophical community that is currently occupied with the mind-brain problem, the book sheds new light on and advances experimental, philosophical, and scholarly research on visual consciousness.
Considers the processes and problems involved in multidisciplinary approaches to vision, focusing not only on detection tasks involving correlations between visual thresholds and cellular sensitivities, but also on the current status of neuron doctrines, and the relationships to be found between s"
The visual system consists of hierarchically organized distinct anatomical areas functionally specialized for processing different aspects of a visual object (Felleman & Van Essen, 1991). These visual areas are interconnected through ascending feedforward projections, descending feedback projections, and projections from neural structures at the same hierarchical level (Lamme et al., 1998). Accumulating evidence from anatomical, functional and theoretical studies suggests that these three projections play fundamentally different roles in perception. However, their distinct functional roles in visual processing are still subject to debate (Lamme & Roelfsema, 2000). The focus of this Research Topic is the roles of feedforward and feedback projections in vision. Even though the notions of feedforward, feedback, and reentrant processing are widely accepted, it has been found difficult to distinguish their individual roles on the basis of a single criterion. We welcome empirical contributions, theoretical contributions and reviews that fit into any one (or a combination) of the following domains: 1) their functional roles for perception of specific features of a visual object 2) their contributions to the distinct modes of visual processing (e.g., pre-attentive vs. attentive, conscious vs. unconscious) 3) recent techniques/methodologies to identify distinct functional roles of feedforward and feedback projections and corresponding neural signatures. We believe that the current Research Topic will not only provide recent information about feedforward/feedback processes in vision but also contribute to the understanding fundamental principles of cortical processing in general.
