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This chapter discusses the general principles of visual coding. It covers the structure of sense organs; types of sensory coding; temporal coding; the geometry of visual space; coding primitives; higher-order sensory systems; and types of perceptual judgment.

This chapter provides an overview of the phenomenology of size perception and the use of instructions to tease apart phenomenal and cognitive aspects. It develops his own recent proposals concerning the geometry of visual space. The chapter proposes that visual space is contracted along the lines of sight. This contraction would explain the apparent convergence of railway tracks, but without invoking a “proximal mode” experience. Parallel railway tracks receding into the distance project converging lines onto the retinas. A true proximal mode representation would show these lines converging as if in a vertical plane. But we experience them as converging while also receding in depth along the ground. The chapter suggests that this calls for a third geometry of visual space, intermediate between a linear perspective projection and full phenomenal constancy (that is, phenomenal experience of the tracks as not converging). The chapter attributes reports of full constancy to cognitive factors.

This chapter talks about how humans are accustomed to seeing the world in high resolution. Compared to many other animals, humans' eyes are not particularly sensitive to light; nor is their sense of color especially good. The undoubted splendors of nature's ultraviolet colors are totally invisible to humans, as are the world's rich natural sources of polarized light. But when it comes to discerning fine spatial detail, few animals come close to humans. But regardless of whether the visual task is to follow a tiny target or to keep track of the physical arrangements of objects in a scene, all aspects of animal life have steered the evolution of spatial vision, particularly the distribution of an eye's sampling stations in visual space.

The visual guidance of bodily motion is conducted by a system, here entitled ‘motion-guiding vision‘, that is separate from the system that furnishes us with visual qualia. The latter is called ‘descriptive vision‘. Vision scientists commonly hold that motion-guiding vision makes no contribution to sensory consciousness. Here it is argued that by giving us the wherewithal physically to make contact with external objects, motion-guiding vision supports perceptual demonstratives and accounts for the ‘feeling of presence‘ that distinguishes seen physical objects from those that are merely pictured or imagined. In this way, motion-guiding vision contributes to our experience of seeing something, though sensory qualia such as colour or shape cannot be traced to it. The visual representation of space is assembled from descriptive and motion-guiding vision.

This chapter outlines the cellular mechanisms that are probably involved in the encoding process of visual space in physiological conditions. It is noted that gaze-dependent visual cells are not able to continually inform about what happens in the same spatial location of the visual field, regardless of eye movements. The real-position behavior could be the result of the work of many strongly modulated gaze-dependent visual cells. Two mechanisms possibly encoding the visual space have been proposed in the posterior parietal cortex (PPC). One is distributed, retinotopically organized, and based on the activity of gaze-dependent visual cells, and the other is direct, nonretinotopically organized, and based on the activity of the so-called real-position cells. It is proposed that the interaction between visual and oculomotor signals, as they occur in gaze-dependent visual cells, represents the first step in the analysis of visual space occurring in almost all areas of the dorsal visual stream. Real-position cells have not been yet detected in the dorsal PPC (areas V6A and ventral intraparietal area [VIP]) and in the ventral premotor cortex, i.e., in regions of the dorsal visual stream that are probably implicated in the visual guidance of actions.

This chapter considers the consequences of blindness and deafness on spatial perception and cognition. A critical question is whether three-dimensional spatial representations can be developed in the absence of auditory or visual input that are sufficient to support accurate spatial perception and cognition. It begins with the discussion of characteristics of visual and auditory space, and the neural representations of visual and auditory space. Moreover, questions of cross-modal effects on spatial perception and cognition in human children and adults are addressed. The research reviewed in this chapter shows that representations of three-dimensional space can be developed in the absence of visual or auditory input that are sufficient to support adaptive spatial perception and cognition.

Space finds its specific definition in different disciplines. This chapter deals with the concept of visual space, and object—or physical—space. It also discusses how the fundamental laws of geometry apply to all spaces, and that includes visual space.

The idea that there might be some sensorimotor interaction in the moon illusion is relatively new, and probably goes back to George Berkeley who argued that both size and distance perception are ultimately based on eye movements and tactile exploration. The sensory aspect of sensorimotor systems is commonly known as proprioception. The proprioceptive mechanisms that contribute to the observer’s knowledge of his own bodily orientation include the vestibular system (the balance organs of the inner ear), the pressure receptors in the skin, and the receptors in the muscles, tendons, and joints. This chapter considers the assumption that proprioceptive information interacts in some way with the visual perception of size and distance, with changes in the observer’s bodily orientation contributing to the moon illusion. The relation between tactile-kinaesthetic space and visual space is controversial, but may not be relevant to the celestial bodies which can only be perceived in visual space.

This chapter takes a look at the most sustained work on the intertextual relationships between Beckett's television drama and other work by him and by others. It examines the association between authored television drama with discourses of ‘quality’, and discusses some matters of visual design, music and literary reference in television plays. It discusses the relationship between uses of visual space in Beckett's television plays and Film and his theatrical works. It also addresses some questions of performance related to ‘theatricality’ and the prevalent motif identified by Beckett critics of increasing formal simplicity or minimalism in his theatre.

Humans often experience difficulty when asked to perform multiple tasks at the same time. Two of the better-known forms of dual-task interference are the attentional blink (AB) effect and the Psychological Refractory Period (PRP) effect. These phenomena have traditionally been studied independently, using divergent methodologies and different dependent measures. This chapter aims to explore the possibility that these dual-task phenomena might reflect the same underlying processing limitation — a central bottleneck. It also discusses how AB and PRP effects are related to other phenomena such as repetition blindness and movements of spatial attention across visual space.

Why does the moon look larger low on the horizon than high in the sky? The apparent horizon enlargement of the moon is commonly known as the moon illusion, a term which became popular in the 20th century. A similar illusion can be observed for the sun, and it is normally called the sun illusion. A third example is the apparent enlargement of the constellations and of the distances between the stars near the horizon. All three cases are called celestial illusions. Interest in the illusion has moved through several different disciplines over the centuries: general science and philosophy, then astronomy, then physiological and meteorological optics, and finally visual psychology. The understanding of visual perception also developed: originally all illusions were assumed to be physical phenomena, but later the distinction between perceptions and reality emerged, and modern psychologists enquire how the brain constructs percepts from retinal stimulation.

In The Phenomenology of Perception, Maurice Merleau-Ponty argues that the world is both preconstituted and made. Here, Merleau-Ponty's interrogation of the experience of blindness followed by sight becomes significant both for his theory and the chapter's theme, the hyperreal. The blind person is constantly challenged to imagine what sight must be like, to attach significations to descriptions of shape and color as they must appear to the sighted. These indications are, however, intellectual constructs, so that if sight is later acquired the seen world differs radically from the one anticipated. However, intelligence cannot achieve the synthesis of touch, the blind person's way of encountering the world, with sight, a synthesis that is only possible in the realm of the sensory itself. The removal of cataracts from the eyes of those blind from birth may unlock the experience of sight but not that of space, which already inheres in tactility, Merleau-Ponty contends. If the patient denies the spatiality of the tactile experience, that is only because it appears impoverished when compared with that of visual space.

The chapter provided a review on the changes of children’s physical environment including their home and outdoor spaces; as well as the opportunities and risks associated with their increasing use of the virtual spaces for leisure, education and learning activities. Associated with the latter, a new form of digital inequality will be examined. Furthermore, against the context of decreasing outdoor play, the importance and benefits of children’s outdoor play for their development and well-being are reviewed. With reference to the latest findings, children’s satisfaction regarding their time use and allocation of it on various activities will also be discussed. Finally, the issues with children’s engagement in part-time employment and being a young carer are explored including the number of children involved in each and the research evidence on the pros and cons of such activities in relation to children’s well-being will also be explored.