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Introduction

Ian P. Howard and Brian J. Rogers

in Seeing in Depth: Volume 1: Basic Mechanics/ Volume 2: Depth Perception 2-Volume Set

This introductory chapter begins with an overview of the chapters in these two volumes. Volume I deals with the basic visual mechanisms used in depth perception. Volume II deals with the perception ... More

This introductory chapter begins with an overview of the chapters in these two volumes. Volume I deals with the basic visual mechanisms used in depth perception. Volume II deals with the perception of three-dimensional space. This is followed by a discussion of basic terms and concepts: binocular vision and stereopsis, and binocular stimuli and processes. The chapter concludes with some guidelines for using the book and suggests other books on seeing in depth.Less

Final Word

Ian P. Howard

in Perceiving in Depth: Volume 3 Other Mechanisms of Depth Perception

This brief chapter reviews the topics discussed in all three volumes.

Development of visual functions

Ian P. Howard and Brian J. Rogers

in Seeing in Depth: Volume 1: Basic Mechanics/ Volume 2: Depth Perception 2-Volume Set

This chapter reviews the development of visual functions, with an emphasis on the development of depth perception. The discussions cover the development of basic functions; the growth of the ... More

This chapter reviews the development of visual functions, with an emphasis on the development of depth perception. The discussions cover the development of basic functions; the growth of the oculomotor system; the development of depth perception; the development of stereoacuity; and binocular correspondence.Less

Three-Dimensional Patterns

Russell L. De Valois and Karen K. De Valois

in Spatial Vision

We live in a three-dimensional world, yet the image of that three-dimensional world is mapped onto our two-dimensional retinae. One of the oldest and most enduring questions regarding spatial vision ... More

We live in a three-dimensional world, yet the image of that three-dimensional world is mapped onto our two-dimensional retinae. One of the oldest and most enduring questions regarding spatial vision is how we analyze those two-dimensional images to derive information about variations in depth from which we construct a three-dimensional percept. There are many visual cues for recognising depth or three-dimensional shape that can be obtained from the monocular visual image. This chapter discusses some of the traditional monocular and binocular cues to depth, with a selective emphasis upon how the types of information processing we know to take place in the striate cortex might play a role in this process.Less

The Computational Period

Alan Gilchrist

in Seeing Black and White

The end of the 1960s marked a new era in lightness perception. The shift from a contrast approach to a computational approach was part of a larger change taking place in psychology, a change that ... More

The end of the 1960s marked a new era in lightness perception. The shift from a contrast approach to a computational approach was part of a larger change taking place in psychology, a change that ended five decades of behaviorist hegemony. The shift from contrast thinking to computational thinking had a profound effect on theories of lightness. During the contrast period, theories had been driven by physiology, primarily in the form of lateral inhibition. Consistent with the behaviorist agenda, physiological validity was pursued as a means for making psychology materialistic. However, the computer provided an alternative definition of materialism. Computers made of copper and silicon store, process, and retrieve information using just code and mechanics.Less

Visual Depth Perception in the Animal Kingdom

Ian P. Howard

in Perceiving in Depth: Volume 3 Other Mechanisms of Depth Perception

Some insight into how depth-detection systems evolved may be gained by studying mechanisms of depth perception in the animal kingdom, from insects to mammals. Most of our knowledge about visual depth ... More

Some insight into how depth-detection systems evolved may be gained by studying mechanisms of depth perception in the animal kingdom, from insects to mammals. Most of our knowledge about visual depth perception has come from cats and primates. But in the animal kingdom there is a great variety of mechanisms of depth perception and some remarkable examples of parallel evolution of these mechanisms. This chapter reviews some of the highly specialized visual mechanisms that have evolved in response to the demands of particular ecological niches. It ends with a discussion of how frontal vision and stereoscopic vision may have evolved.Less

The Gestalt Period

Alan Gilchrist

in Seeing Black and White

The third period of lightness theory saw the arrival of the Gestalt psychologists, with their penetrating insights and dramatic experiments. Rejecting the clumsy two-stage conception of raw ... More

The third period of lightness theory saw the arrival of the Gestalt psychologists, with their penetrating insights and dramatic experiments. Rejecting the clumsy two-stage conception of raw sensations and cognitive interpretation, they proposed a single perceptual process that was parsimonious and elegant. The emergence of Gestalt theory is often tied to the 1912 publication of Max Wertheimer's paper on apparent motion. But the Gestaltists did not really turn their attention to lightness until the early 1930s. When they did, they turned the field upside down. In the short space of five years they published a series of devastating crucial experiments. David Katz, who represented the standard view of lightness, was in retreat on every issue on which Gestalt theory challenged him. The Gestalt period was cut short by the tragic events surrounding World War II.Less

Pathology of binocular vision

Ian P. Howard and Brian J. Rogers

in Seeing in Depth: Volume 1: Basic Mechanics/ Volume 2: Depth Perception 2-Volume Set

Much can be learned about the visual system by studying clinical defects and abnormalities. This chapter reviews defects of depth perception that result from brain damage or genetic defects such as ... More

Much can be learned about the visual system by studying clinical defects and abnormalities. This chapter reviews defects of depth perception that result from brain damage or genetic defects such as albinism, with particular attention paid to the signs and symptoms of loss of binocularity. The discussions cover stereoanomalies; brain damage and stereopsis; abnormal interocular transfer; binocularity and proprioception; and albinism.Less

Development of perceptual functions

Ian P. Howard

in Perceiving in Depth: Volume 1 Basic Mechanisms

This chapter deals with the development of visual perception and auditory localization in human infants. It starts with a review of the development of general visual functions, including visual ... More

This chapter deals with the development of visual perception and auditory localization in human infants. It starts with a review of the development of general visual functions, including visual acuity, sensitivity to orientation and motion, and the development of the visual fields. The development of accommodation and eye movements is then discussed, including the development of eye alignment, pursuit eye movements, saccadic eye movements, and vergence. The next three chapters deal with the development of depth perception, binocular vision, and stereoscopic vision. The chapter ends with a review of the development of auditory localization.Less

Psychophysics and analysis

Ian P. Howard and Brian J. Rogers

in Seeing in Depth: Volume 1: Basic Mechanics/ Volume 2: Depth Perception 2-Volume Set

Many psychophysical and analytic procedures have been used to investigate the visual perception of depth. This chapter provides a general introduction to these procedures. Topics discussed include ... More

Many psychophysical and analytic procedures have been used to investigate the visual perception of depth. This chapter provides a general introduction to these procedures. Topics discussed include psychophysics; the applications of psychophysics; an analysis of linear and nonlinear systems; control theory; time series; Bayesian inference; and concepts of geometry.Less

Introduction

Ian P. Howard

in Perceiving in Depth: Volume 1 Basic Mechanisms

This short chapter outlines the topics discussed in each of the three volumes. It introduces some basic terms, explains the indexes, and provides a list of general references on the subject of depth ... More

This short chapter outlines the topics discussed in each of the three volumes. It introduces some basic terms, explains the indexes, and provides a list of general references on the subject of depth perception.Less

Seeing in depth in different species

Ian P. Howard and Brian J. Rogers

in Seeing in Depth: Volume 1: Basic Mechanics/ Volume 2: Depth Perception 2-Volume Set

This chapter discusses depth vision in animals other than cats and primates. These include invertebrates, fish, amphibian, reptiles, birds, and mammals.

The Classic Period

Alan Gilchrist

in Seeing Black and White

Prior to the 19th century one can find references to the problem of lightness and color constancy, but no sustained experimental program. Most notable in this regard are the insightful writings of ... More

Prior to the 19th century one can find references to the problem of lightness and color constancy, but no sustained experimental program. Most notable in this regard are the insightful writings of the Arab scholar Alhazen, a writer of astonishing modernity, though he lived 1,000 years ago. This chapter chronicles the scientific development of lightness theory that has unfolded in the West during the classic period, when great thinkers such as Alhazen, Ernst Mach, Hermann von Helmholtz, and Ewald Hering defined the basic problem of lightness constancy and staked out opposing solutions. Helmholtz, Hering, and Mach had all observed the effects of depth on lightness, but none of them gave depth the central role it would later be given by the Gestaltists.Less

Functional onset of specific cortical modules

Janette Atkinson

in The Developing Visual Brain

This chapter discusses research results, mainly from the author's research team, providing evidence for the first stages of the neurobiological model, showing sequential onset of different selective ... More

This chapter discusses research results, mainly from the author's research team, providing evidence for the first stages of the neurobiological model, showing sequential onset of different selective channels in visual cortex. Colour processing is weak or absent at birth, but emerges in the first three months. The novel VEP method developed in the Visual Development Unit is described, showing the onset of cortical orientation selectivity, with related behavioural evidence for infants' orientation discrimination. For motion selectivity, optokinetic nystagmus (OKN) shows an early subcortical directional mechanism, with characteristic monocular asymmetries. At two to three months, VEP evidence shows a cortical directional mechanism, which also contributes to symmetrical OKN. VEP and behavioural methods show cortical responses to binocular correlation and disparity, first appearing at three-four months. This is discussed in relation to vergence control, strabismus, stereo depth perception, and how the pre-binocular cortex may be organized.Less

Convergence as a Function of Chromatic Contrast: A Possible Contributor to Depth Perception?

Galina V. Paramei and Wolfgang Jaschinski

in Normal and Defective Colour Vision

This chapter addresses the question of whether vergence — an oculomotor component of binocular vision — is related to the variation of chromatic information in stimuli, thereby contributing to ... More

This chapter addresses the question of whether vergence — an oculomotor component of binocular vision — is related to the variation of chromatic information in stimuli, thereby contributing to binocular ‘colour-and-depth’ perception. In particular, the chapter examined whether a near-vergence response elicited by a fusion stimulus would change when stimulus chromatic contrast is varied. The results show that chromatic contrast yields information for a distance cue in dichoptically presented stimuli, as indicated by a systematic increase of the vergence error with reducing contrast. Similarly, reducing luminae contrast results in increasing vergence error.Less

Grouping and Segmentation of Visual Objects by Baboons (Papio papio) and Humans (Homo sapiens)

Joël Fagot and Isabelle Barbet

in Comparative Cognition: Experimental Explorations of Animal Intelligence

This chapter discusses the results of a series of experiments aimed at investigating visual-information processing in baboons. Two lines of ... More

This chapter discusses the results of a series of experiments aimed at investigating visual-information processing in baboons. Two lines of research on baboons are presented in this chapter. The first one explores the processes of perceptual grouping. In comparison to humans when similarly tested, baboons barely group spatially separated elements into a single percept. The second one addresses the issue of depth perception. Baboons perceive depth when presented with pictorial depth cues, but the study also highlights human–baboon differences in the processing of occlusion cues as indicators of depth. A local precedence effect was observed in baboons, in contrast to humans, who showed a global precedence effect. Experiments further revealed that local precedence in baboons is a direct consequence of their difficulty in overcoming the separation between the local elements, a necessary process for perceiving the whole. Moreover, baboons perceive the corridor illusion, suggesting that they gain depth information from the pictorial cues available in the image background.Less

Perception

Lenn E. Goodman and D. Gregory Caramenico

in Coming to Mind: The Soul and Its Body

Reductive accounts of the soul took root in ancient and early modern notions that perception is passive, ultimately a matter of mechanical impacts on our sense organs that somehow become signals, ... More

Reductive accounts of the soul took root in ancient and early modern notions that perception is passive, ultimately a matter of mechanical impacts on our sense organs that somehow become signals, “sense-data,” as they were called in the last century, long construed as atomic, even unanalyzable. Yet close study of perception, physiologically and psychologically, reveals active work in the brain and our sense organs themselves in every perceptual experience: Even from the start we integrate, organize, relate, and interpret all that we encounter perceptually. The work of the Gestalt psychologists proves especially relevant here. But so does that of color theorists, linguists, artists and musicians, and the scientists who study olfaction, taste, and touch, depth perception – and the fascinating phenomena of synaesthesia, and our remarkable ability to follow the thread of a conversation, even in a noisy room. Color is not just light of a given wavelength; a tone or chord is not just a sequence of vibrations in the air. To be heard those vibrations must be worked with. To be seen wave patterns in the visible spectrum must be taken up and transformed. The synthetic work of the soul translates physical effects into experiences and ideas.Less