Download or read book Visual Object Processing written by Glyn W. Humphreys and published by Routledge. This book was released on 2017-03-27 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Originally published in 1987, this book, attempted to bring together work by researchers concerned with the functional and neurological mechanisms underlying visual object processing, and the ways in which such mechanisms can be neurologically impaired. The editors termed it a ‘Cognitive Neuropsychological’ approach, because they believed it tried to relate evidence from neurological impairments of visual object processing to models of normal performance in a new and important way. Two broad aims are apparent. One is to test models of normal performance by evaluating how well the models account for the patterns of impairment and preservation of abilities that can occur following brain damage. The other is to use models of normal performance to further their understanding of acquired disorders of visual object processing. These aims distinguish the approach from neuropsychological work whose primary aim is to relate acquired deficits to the sites of damage, and from work in the field of cognitive psychology which attempts only to develop models of normal performance.
Download or read book Visual Object Processing written by and published by . This book was released on 1987 with total page 317 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Bottom up and Top down Manipulations on Visual Object Processing Across the Brain written by Lior Bugatus and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Object recognition is an incredibly important process in day to day life, and is accomplished by the human visual system automatically and effortlessly. However, this process is rarely done in isolation from goal-oriented behavior (or task) performed by the subject. Though much is known about the passive processing of objects in the visual system, far less is understood in both: (1) How tasks affect known responses to objects in visual cortex, and (2) How objects are represented in regions of higher cognition such as prefrontal cortex. Chapter I provides an overview of the existing knowledge regarding object recognition and visual processing of objects, the effects of task engagement on responses in high-level visual cortex, and what is currently known on representations of objects in prefrontal cortex. The study described in chapter II examined how the information content of object classes, or category representations, in different cortical regions changed across three qualitatively different tasks. Here we find that while responses in high-level visual cortex contain robust and task-general representations of visual categories, responses in prefrontal cortex are flexible and task-dependent, supporting their respective functional roles. The study in chapter III further dives into the effects of top-down signals, as well as bottom-up signals, in finer increments and in smaller (and independently derived) of the cortical expanses explored in the first study. The findings from this study reveal a far richer functional heterogeneity in high-level visual cortex than was previously assumed, capturing a diverse set of response profiles to bottom-up and top-down manipulations, as well as their interactions. In prefrontal cortex, no areas are engaged by purely bottom-up manipulation of stimulus, and only a small subset is engaged by the on-task condition, alluding to hypothesized mechanisms of attention. Together, these results expand what is known about the effects of task in high-level visual cortex, as well as the involvement of prefrontal cortex in object processing.
Download or read book The Neurobiology of Cognition and Behavior written by John Hart (Jr.) and published by Oxford University Press. This book was released on 2016 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Neurobiology of Cognition and Behavior" is a cognitive neuroscience that maps cognitive/behavioral units with anatomical regions in the human brain. The brain-behavioral associations are based on functional neuroimaging combined with lesion studies. The findings will be used to explain differences in clinical syndromes with videos of patients included.
Download or read book Effects of Expectation on Visual Object Processing in Humans written by Amrita Monica Puri and published by . This book was released on 2008 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Feedforward and Feedback Processes in Vision written by Hulusi Kafaligonul and published by Frontiers Media SA. This book was released on 2015-07-10 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Semantic Scene Context Effects on Visual Object Processing written by Elisa Kuo-Min Cheng and published by . This book was released on 1999 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Object Recognition in Man Monkey and Machine written by Michael J. Tarr and published by MIT Press. This book was released on 1999-03-15 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: The contributors bring a wide range of methodologies to bear on the common problem of image-based object recognition. These interconnected essays on three-dimensional visual object recognition present cutting-edge research by some of the most creative neuroscientific, cognitive, and computational scientists in the field. Cassandra Moore and Patrick Cavanagh take a classic demonstration, the perception of "two-tone" images, and turn it into a method for understanding the nature of object representations in terms of surfaces and the interaction between bottom-up and top-down processes. Michael J. Tarr and Isabel Gauthier use computer graphics to study whether viewpoint-dependent recognition mechanisms can generalize between exemplars of perceptually defined classes. Melvyn A. Goodale and G. Keith Humphrey use innovative psychophysical techniques to investigate dissociable aspects of visual and spatial processing in brain-injured subjects. D.I. Perrett, M.W. Oram, and E. Ashbridge combine neurophysiological single-cell data from monkeys with computational analyses for a new way of thinking about the mechanisms that mediate viewpoint-dependent object recognition and mental rotation. Shimon Ullman also addresses possible mechanisms to account for viewpoint-dependent behavior, but from the perspective of machine vision. Finally, Philippe G. Schyns synthesizes work from many areas, to provide a coherent account of how stimulus class and recognition task interact. The contributors bring a wide range of methodologies to bear on the common problem of image-based object recognition.
Download or read book Object Recognition Attention and Action written by Naoyuki Osaka and published by Springer Science & Business Media. This book was released on 2009-03-12 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Human object recognition is a classical topic both for philosophy and for the natural sciences. Ultimately, understanding of object recognition will be promoted by the cooperation of behavioral research, neurophysiology, and computation. This original book provides an excellent introduction to the issues that are involved. It contains chapters that address the ways in which humans and machines attend to, recognize, and act toward objects in the visual environment.
Download or read book Emergent Techniques for Assessment of Visual Performance written by National Research Council and published by National Academies Press. This book was released on 1985-01-01 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Representation and Recognition in Vision written by Shimon Edelman and published by MIT Press. This book was released on 1999 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shimon Edelman bases a comprehensive approach to visual representation on the notion of correspondence between proximal (internal) and distal similarities in objects. Researchers have long sought to understand what the brain does when we see an object, what two people have in common when they see the same object, and what a "seeing" machine would need to have in common with a human visual system. Recent neurobiological and computational advances in the study of vision have now brought us close to answering these and other questions about representation. In Representation and Recognition in Vision, Shimon Edelman bases a comprehensive approach to visual representation on the notion of correspondence between proximal (internal) and distal similarities in objects. This leads to a computationally feasible and formally veridical representation of distal objects that addresses the needs of shape categorization and can be used to derive models of perceived similarity. Edelman first discusses the representational needs of various visual recognition tasks, and surveys current theories of representation in this context. He then develops a theory of representation that is related to Shepard's notion of second-order isomorphism between representations and their targets. Edelman goes beyond Shepard by specifying the conditions under which the representations can be made formally veridical. Edelman assesses his theory's performance in identification and categorization of 3D shapes and examines it in light of psychological and neurobiological data concerning the object-processing stream in primate vision. He also discusses the connections between his theory and other efforts to understand representation in the brain.
Download or read book Using EEG to Examine the Top Down Effects on Visual Object Processing written by Joseph D. Borders and published by . This book was released on 2019 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: Object recognition entails a complex interplay between top-down and bottom-up signals. Yet, limited research has investigated the mechanisms through which top-down processes, such as task context and behavioral goals impact the neural basis of visual object processing. Using electroencephalography (EEG), we studied the temporal dynamics of task and object processing to identify how early the impact of task can be observed. We recorded ERPs from participants as they viewed object images from four categories spanning animacy (Inanimate: roller-skate, motorbike; Animate: cow, butterfly) and size (Large: motorbike, cow; Small: roller-skate, butterfly) dimensions under four task conditions comprising conceptual (naturalness, size) and perceptual (color, tilt) dimensions. We did not find evidence of behavioral goals, as manipulated by the task context, modulating early visual object representations, as indexed by early visual ERPs (P1, N1, P2), in extrastriate cortex. Additional analyses revealed that task-related processing occurred predominately in later time windows (300-600ms) within frontoparietal regions. Irrespective of task, we also observed a variety of object category effects across early visual ERPs. These findings support previous neuroimaging results suggesting object representations in occipitotemporal cortex are organized based on their animacy and real-world size, and, importantly, these ERP results indicate these organizational principles can be observed in relatively early stages along the visual processing hierarchy. Taken together, this work adds to the body of psychological and neuroscientific research examining how and when top-down and bottom-up signals interact to form the basis of visual object processing, facilitating of high-level vision.
Download or read book Vision written by David Marr and published by MIT Press. This book was released on 2010-07-09 with total page 429 pages. Available in PDF, EPUB and Kindle. Book excerpt: Available again, an influential book that offers a framework for understanding visual perception and considers fundamental questions about the brain and its functions. David Marr's posthumously published Vision (1982) influenced a generation of brain and cognitive scientists, inspiring many to enter the field. In Vision, Marr describes a general framework for understanding visual perception and touches on broader questions about how the brain and its functions can be studied and understood. Researchers from a range of brain and cognitive sciences have long valued Marr's creativity, intellectual power, and ability to integrate insights and data from neuroscience, psychology, and computation. This MIT Press edition makes Marr's influential work available to a new generation of students and scientists. In Marr's framework, the process of vision constructs a set of representations, starting from a description of the input image and culminating with a description of three-dimensional objects in the surrounding environment. A central theme, and one that has had far-reaching influence in both neuroscience and cognitive science, is the notion of different levels of analysis—in Marr's framework, the computational level, the algorithmic level, and the hardware implementation level. Now, thirty years later, the main problems that occupied Marr remain fundamental open problems in the study of perception. Vision provides inspiration for the continuing efforts to integrate knowledge from cognition and computation to understand vision and the brain.
Download or read book Words and Pictures written by Vanja Vucetic and published by . This book was released on 2008 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Visual Neurosciences written by John Simon Werner and published by MIT Press. This book was released on 2004 with total page 975 pages. Available in PDF, EPUB and Kindle. Book excerpt: An essential reference book for visual science.
Download or read book A Case Study in Visual Agnosia Revisited written by Glyn Humphreys and published by Psychology Press. This book was released on 2013-10-15 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt: Visual agnosia is a rare but fascinating disorder of visual object recognition that can occur after a brain lesion. This book documents the case of John, who worked intensively with the authors for 26 years after acquiring visual agnosia following a stroke. It revisits John’s case over twenty years after it was originally described in the book To See But Not To See, in 1987. As in the previous book, the condition is illuminated by John and his wife, Iris, in their own words. A Case Study in Visual Agnosia Revisited discusses John’s case in the context of research into the cognitive neuroscience of vision over the past twenty years. It shows how John’s problems in recognition can provide important insights into the way that object recognition happens in the brain, with the results obtained in studies of John’s perception being compared to emerging work from brain imaging in normal observers. The book presents a much fuller analysis of the variety of perceptual problems that John experienced, detailing not only his impaired object recognition but also his face processing, his processing of different visual features (colour, motion, depth), his ability to act on and negotiate his environment, and his reading and writing. A Case Study in Visual Agnosia Revisited will be a key reference for those concerned with understanding how vision is implemented in the brain. It will be suitable for both undergraduate students taking courses in cognitive psychology and neuropsychology, and also researchers in the cognitive neuroscience of vision. The presentation of John’s case, and the human aspects of the disorder, will also be of great interest to a general audience of lay people interested in perception.
Download or read book Visual Processing written by Roger Watt and published by Psychology Press. This book was released on 2022-03-01 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: This highly original and interesting monograph puts forward ideas on visual processing and representation in the early stages of visual perception, and examines the computational requirements of the system and its psychological performance. Initially the author considers the computational theory of how the maximum amount of useful information about the scene can be registered from the variations in light intensity in the retinal image. He then goeson to address the question of just what it means to say that the visual system measures spatial aspects of the retinal image, and the consequences of the inevitable distortions that are introduced. He believes that the calculation of spatial position within a distorted metric is not trivial and requires dynamic processes with memory and control. Finally, Dr. Wan argues that the strength of the link between the low-level approaches of psychophysics and computational theory and high-level approaches of cognitive visual function lies in the logic of the arguments that indicate the computational need for control. This Essay will be of great interest to researchers in computer vision, perception, cognitive science and cognitive psychology.
