Visual Object Processing

Visual Object Processing PDF Author: Glyn W. Humphreys
Publisher: Routledge
ISBN: 1315456834
Category : Psychology
Languages : en
Pages : 318

Get Book Here

Book Description
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.

Visual Object Processing

Visual Object Processing PDF Author: Glyn W. Humphreys
Publisher: Routledge
ISBN: 1315456834
Category : Psychology
Languages : en
Pages : 318

Get Book Here

Book Description
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.

The Neurobiology of Cognition and Behavior

The Neurobiology of Cognition and Behavior PDF Author: John Hart (Jr.)
Publisher: Oxford University Press
ISBN: 0190219033
Category : Medical
Languages : en
Pages : 257

Get Book Here

Book Description
"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.

Visual Object Processing

Visual Object Processing PDF Author:
Publisher:
ISBN:
Category : Visual perception
Languages : en
Pages : 317

Get Book Here

Book Description


Effects of Bottom-up and Top-down Manipulations on Visual Object Processing Across the Brain

Effects of Bottom-up and Top-down Manipulations on Visual Object Processing Across the Brain PDF Author: Lior Bugatus
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
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.

Effects of Expectation on Visual Object Processing in Humans

Effects of Expectation on Visual Object Processing in Humans PDF Author: Amrita Monica Puri
Publisher:
ISBN:
Category :
Languages : en
Pages : 214

Get Book Here

Book Description


Feedforward and Feedback Processes in Vision

Feedforward and Feedback Processes in Vision PDF Author: Hulusi Kafaligonul
Publisher: Frontiers Media SA
ISBN: 2889195945
Category : Feedback
Languages : en
Pages : 153

Get Book Here

Book Description
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.

Emergent Techniques for Assessment of Visual Performance

Emergent Techniques for Assessment of Visual Performance PDF Author: National Research Council
Publisher: National Academies Press
ISBN:
Category : Medical
Languages : en
Pages : 75

Get Book Here

Book Description
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.

Vision

Vision PDF Author: David Marr
Publisher: MIT Press
ISBN: 0262514621
Category : Psychology
Languages : en
Pages : 429

Get Book Here

Book Description
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.

Perception of Faces, Objects, and Scenes

Perception of Faces, Objects, and Scenes PDF Author: Mary A. Peterson
Publisher: Advances in Visual Cognition
ISBN: 0195313658
Category : Psychology
Languages : en
Pages : 402

Get Book Here

Book Description
From a barrage of photons, we readily and effortlessly recognize the faces of our friends, and the familiar objects and scenes around us. However, these tasks cannot be simple for our visual systems--faces are all extremely similar as visual patterns, and objects look quite different when viewed from different viewpoints. How do our visual systems solve these problems? The contributors to this volume seek to answer this question by exploring how analytic and holistic processes contribute to our perception of faces, objects, and scenes. The role of parts and wholes in perception has been studied for a century, beginning with the debate between Structuralists, who championed the role of elements, and Gestalt psychologists, who argued that the whole was different from the sum of its parts. This is the first volume to focus on the current state of the debate on parts versus wholes as it exists in the field of visual perception by bringing together the views of the leading researchers. Too frequently, researchers work in only one domain, so they are unaware of the ways in which holistic and analytic processing are defined in different areas. The contributors to this volume ask what analytic and holistic processes are like; whether they contribute differently to the perception of faces, objects, and scenes; whether different cognitive and neural mechanisms code holistic and analytic information; whether a single, universal system can be sufficient for visual-information processing, and whether our subjective experience of holistic perception might be nothing more than a compelling illusion. The result is a snapshot of the current thinking on how the processing of wholes and parts contributes to our remarkable ability to recognize faces, objects, and scenes, and an illustration of the diverse conceptions of analytic and holistic processing that currently coexist, and the variety of approaches that have been brought to bear on the issues.

Representation and Recognition in Vision

Representation and Recognition in Vision PDF Author: Shimon Edelman
Publisher: MIT Press
ISBN: 9780262050579
Category : Computers
Languages : en
Pages : 378

Get Book Here

Book Description
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.