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This chapter argues that the minds of all animals (even honey bees) are organized around a perception/belief/desire/planning/motor-control architecture. There are also multiple modules for generating beliefs, for generating desires and other forms of motivation, for storing those states in memory, and for controlling action. Evidence of dual visual systems in mammals, and against the existence of any sort of general learning is presented. It is argued that some animals might utilize mental rehearsal of action schemata to increase the flexibility of their decision making.

This chapter reviews the history of the subject to the early twentieth century. The chapter is organized as follows. Section 2.1 discusses the history of visual science, covering the Greeks; the Arabs; Europe to the eighteenth century; the microscopic structure of the visual system; the discovery of cortical visual areas; the discovery of perspective; the advent of instruments; and the empiricist-nativist controversy. Section 2.2 deals with the history of binocular vision, covering Ptolemy on binocular vision; Alhazen on binocular vision; Europe to the eighteenth century; the horopter; and the physiology of stereopsis. Section 2.3 discusses the history of visual display systems, covering early display systems; the advent of the stereoscope; stereophotography; and stereoscopic movies.

This chapter explores a way in which visual processing may involve innate constraints and attempts to show how such processing overcomes one enduring challenge to nativism. In particular, many challenges to nativist theories in other areas of cognitive psychology (e.g., ‘theory of mind’, infant cognition) have focused on the later development of such abilities, and have argued that such development is in conflict with innate origins (since those origins would have to be somehow changed or overwritten). Innateness, in these contexts, is seen as antidevelopmental, associated instead with static processes and principles. In contrast, certain perceptual models demonstrate how the very same mental processes can both be innately specified and yet develop richly in response to experience with the environment. This process is entirely unmysterious, as shown in certain formal theories of visual perception, including those that appeal to spontaneous endogenous stimulation and those based on Bayesian inference.

This chapter provides an overview of the reading networks and their implications for our understanding of developmental dyslexia. In particular, it focuses on the sublexical letter-sound conversion and the lexical direct visual-semantic routes for reading that rely greatly on accurate visual input. It proposes that the visual magnocellular system is crucial for this processing.

This chapter begins with a discussion of how visual mental imagery has progressed from a time of introspective analysis alone to the examination of the brain circuitry that underlies it. This sets the stage for a discussion of the possible relevance of imagery research for health. Topics covered include mental simulation of aversive events, imagery and cognitive restructuring, and imagery and mind-body interactions.

The human visual system consists of a system for inspecting objects, starting with the fovea in the retina, and a system for noticing which objects should be inspected, and directing the eyes to look at them. In daylight, the cones are the photoreceptors used, with three types, leading to trichromatic color vision. At night, the rods are active. As the eyes move, the world appears to be stationary, which is accomplished by noticing and carrying forward a limited number of objects from one snapshot to the next. Most aspects of vision are relative—the brightness, color, motion, and depth of an object are all seen relative to the background. Finally, absence of activity in the neurons of the visual system is interpreted as continuity with the rest of the scene, so that lesions in the brain may simply not be noticed.

The chapter starts with a brief outline of how eyes evolved from simple eyespots to complex camera-like eyes. An account of the development of the visual system starts with a description of methods used to study neural development. A description of the mechanisms that guide development of the eye and visual pathways is followed by an account of the development of the brain. Topics include axonal guidance, synaptogenesis, formation of cortical layers and connections, neural plasticity, and formation of ocular dominance columns in the visual cortex. An account is given of recently discovered epigenetic mechanisms in which stimulus-induced neural activity controls genes that express the proteins required in each location of the developing visual system.

This chapter presents a detailed neuroanatomical and neurophysiological account of visual processing in the primate brain. It suggests that consideration of the natural requirements for detecting and identifying behaviorally meaningful stimuli such as insects, fruits, and the facial identities and expressions of other individuals, likely played an important role in the evolution of visual processing and, by extension, the evolution of cognition in primates.

This chapter argues that visual information is encoded in terms of spatial frequency because the visual world is periodic and can thus be more efficiently encoded in the spatial frequency domain than in the pure space domain. However, insofar as visual patterns are only locally periodic, a local but not a global frequency analysis would take advantage of such redundant patterns. It may well be that spatial periodicities in fact rarely extend over more than a small fraction of the visual field. Thus, spatially localized, patch-by-patch spatial frequency encoding would be most adaptive, more so than more global processing.

This chapter reviews the features of the visual and oculomotor systems that are particularly important for understanding active vision. First, the chapter describes the inhomogeneity of the visual projections and the consequences of the resulting inhomogeneity on visual abilities. Human vision has a high resolution fovea at the centre and visual ability falling off quickly into peripheral vision. Second, the evidence for multiple types of parallel processing within the visual and oculomotor system is reviewed. Third, the basic characteristics of the oculomotor system are described and different types of eye movement are identified, followed by a more detailed description of saccadic eye movements: the fast ballistic eye movements that move the fovea to point at regions of interest.

This chapter examines past neuropsychological and brain imaging data of the Japanese language to shed light on the universal and language-specific aspects of the cerebral reading system. First, it discusses several types of script-specific alexia under the current framework of the functional architecture of the ventral visual system. It then looks at previous functional brain imaging evidence for possible intra- and inter-hemispheric differences between two scripts. Finally, it presents functional magnetic resonance imaging (fMRI) studies on cross-script convergence of kanji and kana, rather than between-script difference, and argues for a possible language-specific exploitation of the visual word recognition system in the occipitotemporal cortex.

The fact that inputs from two eyes feed into a common mechanism gives rise to several interesting problems. Signals from the two eyes that arise from the same object must be distinguished from signals that arise from spurious superimposition of non-matching stimuli. Matching signals falling on neighbouring points on the two retinas project to the same region in the visual cortex and fuse to create the impression of one image. Non-matching images falling on the same region in the two eyes rival for access to the visual system. This chapter deals with these issues. The discussions cover binocular fusion; dichoptic colour mixture; binocular rivalry; the spatial zones of rivalry; the generality of binocular suppression; aftereffects from suppressed images; rivalry and stereopsis; cognition and binocular rivalry; models of binocular rivalry; and the neurology of binocular rivalry.

This chapter begins with a discussion of the illustrates four key steps that the visual system follows in perceiving objects: (1) segmentation of the visual scene into its components, components that are discriminable by virtue of differences in color, luminance, texture, distance, shape, orientation, and motion; (2) assembly of the components derived from Step 1 into units; (3) perception of the units as continuous across space and time; and (4) deduction of the three-dimensional shape of the assembled units from limited views. The chapter presents data that bear principally on development of the second and third aspects of object perception: assembling visual fragments into units, and perceiving continuity across space and time. It posits a strong role for learning in achieving veridical object perception in the first several postnatal months: infants learn by doing (i.e., via development of eye movements) and infants learn by seeing (i.e., via exposure to objects in the environment).

This chapter further develops a multiple-subsystems hypothesis positing distinct transient and sustained subsystems in high-level vision, and relates it to knowledge about independent pathways in early vision. It contrasts the transient-sustained hypothesis with the Ungerleider–Mishkin what-where hypothesis and the Milner–Goodale perception-action hypothesis, arguing that AH's results are readily accommodated by the proposal but pose challenges for both the Ungerleider–Mishkin and Milner–Goodale positions. Finally, it shows that the basic findings adduced in support of the what-where and perception-action hypotheses are entirely consistent with assumptions about the functional architecture of the higher-level visual system.

This chapter presents results concerning AH's head and eye movements and the consequences of these movements for her visual location perception. It shows that AH often moved her head and eyes in the wrong direction when attempting to orient toward a visual stimulus. It then reports a far more surprising result: AH's misperceptions of object location often remained stable across head and eye movements. For this latter result, the chapter offers a speculative interpretation concerning the processes that generate high-level visual location representations. Finally, it discusses the implications of AH's performance for issues concerning the levels of the visual system implicated in conscious visual experience.

This introductory chapter talks about how every creature is guided by its eyes as it carries out its accustomed behaviors. Each animal's eyes allows it to execute the behavior necessary for its survival. This study of how visual systems function to meet the ecological needs of animals is called visual ecology. Researchers who work at various levels of inquiry, from genes to behavior, call themselves visual ecologists, but all are primarily concerned with how animals use vision for natural tasks and behaviors. Although the outcomes of visual ecological research may well have implications for health or may be applicable for use in engineering or technology, the research itself centers on the animal of interest and on how it employs its visual system to meet its own ecological needs.

This chapter provides a background on linear systems analysis to allow the reader to follow the applications to visual problems discussed in this book. Specifically, it discusses the Fourier theorem and its applications to vision. Fourier analysis is a powerful tool for studying complex waveforms, allowing one to specify quantitatively the characteristics of any complex waveform or shape. Another major advantage in its application to vision is that it gives a common basis by which one can examine optical, physiological, and psychophysical data. The principal limitation in its application to visual problems is the underlying assumption of linearity, a condition that is only met by the visual system under limited conditions.

This chapter reviews the development of the visual system in birds and mammals. It briefly describes the first phase, when the system is organized without much information from sensory organs. It also discusses the period when sensory information starts to affect the wiring of the visual system nuclei, and combine the development of visually guided behavior with that of the visual system. Finally, it deals with the question of how early experience helps birds to recognize and memorize important visual features of their life, as for example, parents or sexual partner; and provides some ideas about the neuronal mechanisms underlying such early learning events, which have been called imprinting because of their extreme stability of memorization.