This book is an international collection of contributions from academia, industry and the armed forces. It addresses current and emerging Spatial Vision Models and their application to the understanding, prediction and evaluation of the tasks of target detection and recognition. The discussion in many of the chapters is framed in terms of military targets and military vision aids. However, the techniques analyses and problems are by no means limited to this area of application. The detection and recognition of an armored vehicle from a reconnaissance image are performed by the same visual system used to detect and recognize a tumor in an X-ray. The analysis of the interaction of the human visual system with night vision devices is not different from the analysis needed in the case of an operator examining structures using a remote (endoscopic) camera, etc. The book is organized into three general sections. The first covers basic modeling of central (foveal) vision and its theoretical background. The second is centered on the evaluation of model performance in applications, while the third is dedicated to aspects of peripheral vision modeling and the expansion of peripheral modeling to include visual search.

Visual search requires humans to detect a great variety of target objects in scenes cluttered by other objects or the natural environment. It is unknown whether the brain contains a general purpose detection mechanism to code the presence of a wide variety of categories of objects embedded in natural scenes. We provide evidence for a feature-independent coding mechanism for detecting behaviorally relevant targets in natural scenes in the dorsal frontoparietal network. Pattern classifier using data from single-trial fMRI activity in the dorsal frontoparietal network reliably predicted the presence of 384 different target objects and also the observer's choices. IPS activity correlated with observers' decision confidence and with the task-difficulty of individual images. These results could not be explained based on physical differences across images or eye-movements. Thus, the dorsal frontoparietal network detects behaviorally relevant targets in natural scenes independent of the defining visual features and is akin to the priority map in monkey lateral intra-parietal cortex.

At the fascinating frontiers of neurobiology, mathematics and psychophysics, this book addresses the problem of human and computer vision on the basis of cognitive modeling. After recalling the physics of light and its transformation through media and optics, Hrault presents the principles of the primate's visual system in terms of anatomy and functionality. Then, the neuronal circuitry of the retina is analyzed in terms of spatio?temporal filtering. This basic model is extended to the concept of neuromorphic circuits for motion processing and to the processing of color in the retina. For more in-depth studies, the adaptive non-linear properties of the photoreceptors and of ganglion cells are addressed, exhibiting all the power of the retinal pre-processing of images as a system of information cleaning suitable for further cortical processing. As a target of retinal information, the primary visual area is presented as a bank of filters able to extract valuable descriptors of images, suitable for categorization and recognition and also for local information extraction such as saliency and perspective. All along the book, many comparisons between the models and human perception are discussed as well as detailed applications to computer vision.

Pattern Recognitions by Humans and Machines, Volume 2: Visual Perceptions covers aspects of research on visual perception. The book discusses visual form perception, figure-ground organization, and the spatial and temporal responses of the visual system; eye movements; and visual pattern perception. The text also describes a computer vision model based on psychophysical experiments; perspectives from brain theory and artificial intelligence; and the capacity to extract shape properties and spatial relations among objects and objects' parts. Knowledge-mediated perception is also considered. Psychologists and people involved in the study of visual perceptions will find the book useful.

It has become accepted in the neuroscience community that perception and performance are quintessentially multisensory by nature. Using the full palette of modern brain imaging and neuroscience methods, The Neural Bases of Multisensory Processes details current understanding in the neural bases for these phenomena as studied across species, stages of development, and clinical statuses. Organized thematically into nine sub-sections, the book is a collection of contributions by leading scientists in the field. Chapters build generally from basic to applied, allowing readers to ascertain how fundamental science informs the clinical and applied sciences. Topics discussed include: Anatomy, essential for understanding the neural substrates of multisensory processing Neurophysiological bases and how multisensory stimuli can dramatically change the encoding processes for sensory information Combinatorial principles and modeling, focusing on efforts to gain a better mechanistic handle on multisensory operations and their network dynamics Development and plasticity Clinical manifestations and how perception and action are affected by altered sensory experience Attention and spatial representations The last sections of the book focus on naturalistic multisensory processes in three separate contexts: motion signals, multisensory contributions to the perception and generation of communication signals, and how the perception of flavor is generated. The text provides a solid introduction for newcomers and a strong overview of the current state of the field for experts.

An exciting new line of research that investigates the impact of one’s own hands on visual processing has flourished in the past several years. Specifically, several studies have demonstrated that objects near the hands receive prioritized attention, enhanced perceptual sensitivity, altered figure-ground assignment, prolonged and detail-oriented processing, and improved visual working memory. Taken together, these results demonstrate that the visual system reveals a new pattern of processing when one's hands are in proximity of viewed objects. Therefore, the vast majority of studies on visual processing, in which one's hands are kept away from the stimuli, may constitute but one side of a more complex story of the inner workings of the visual system. With several consistent behavioral demonstrations of hand-altered vision now in the literature, the present challenge facing this growing field, and the aim of this Research Topic, is four-pronged: 1) Isolate and elucidate the underlying cognitive and neural mechanisms of hand-altered vision; 2) Map the parameters and conditions of hand-nearness that permit/prevent the onset or maintenance of hand-altered vision; 3) Determine the consequences of hand-altered vision for higher-level cognition and assess its applied potential (e.g., as a neuropsychological intervention); and, 4) Present a cohesive and predictive theoretical account of hand-altered vision. We welcome submissions that fit into any one (or a combination) of the above domains. For behavioral research, we particularly encourage submissions that are relevant to the advancement of our understanding of the neural mechanisms of hand-altered vision (e.g., demonstrations that might corroborate or disconfirm proposed neural systems).