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It's in the Eye of the Beholder: Spatial Language and Spatial Memory Use the Same Perceptual Reference Frames Lipinski et al.Spatial language provides an effective domain to examine the connection between non‐linguistic and linguistic systems because it is an unambiguous case of linguistic and sensori‐motor systems coming together. In the present work we use a process‐based theory of spatial working memory—the Dynamic Field Theory—to generate and test novel predictions regarding the time‐dependent link between spatial memory and spatial language. Our analysis and empirical findings suggest that focusing on the processes underlying spatial language, rather than representations per se, can produce more constrained theories of the connection between sensorimotor and linguistic systems.

This chapter examines the role of embodiment in the development of spatial cognition. Using evidence from normally developing children and individuals with Williams syndrome—a rare genetic deficit leading to severe spatial impairment—we argue that, although interactions between the body and world play an interesting role in the development and use of rich spatial representations of the world, these interactions by themselves cannot be a substitute for abstract representations. Indeed, we will argue that real advances in developing spatial cognitive functions require that people become untethered from the physical world—capable of thought that goes beyond our current connections with the world. This kind of thought requires spatial representations that are rich, robust, and amenable to mental manipulation.

This chapter reviews current knowledge about spatial representations in medial entorhinal cortex (MEC), its possible role in navigation, and how cell ensembles in MEC might contribute to the spatial component of hippocampal place cell representations. The discovery of a metric representation of self-location in MEC suggests that the primary function of the hippocampus is not the dynamic computation of location. Although the animal's position can be predicted from the collective firing of grid cell ensembles, it remains to be determined whether readout occurs within the entorhinal cortex or in one or several of its hippocampal or parahippocampal target structures. The contextual specificity of hippocampal representations suggests that during encoding, the hippocampus associates input from the self-motion-based coordinate system in MEC with other contextual information such as information from lateral entorhinal cortex (LEC). The possible recoding of spatial information from a positional code in MEC onto statistically independent, context-sensitive cell ensembles in high-capacity networks of the hippocampus is probably crucial for the successful storage of episodic memory.

The use of computational models has been invaluable for exploring the link between neurons and behavior, enabling hypothetical mechanisms to be defined precisely and examined quantitatively. This chapter reviews many of these models, including models of spatial functions, models of more general associative mnemonic functions, models that stress feedforward processing through the hippocampal system, and those stressing recurrent processing within it. Spatial models are reviewed first, as they are most firmly rooted in the known electrophysiology of the region. These models cover both the representation of the animal's spatial location and orientation and the use of this information in spatial navigation. The models of mnemonic function, specifically associative or episodic memory, follow from Marr's seminal 1971 model. This model is used as a generic framework in which to consider the various subsequent developments to it. Finally, the chapter reviews those models attempting to bring together the spatial and mnemonic functions of the hippocampus.

This chapter reviews studies in which monkey hippocampal formation (HF) neurons were analyzed during performance of either different tasks in the same spatial environment or essentially the same task in different spatial environments. It is shown that the HF represents allocentric space with contexts, reference frames, or a chart system in which different assemblies of different HF neurons with different spatial tuning are created for each different environment or behavioral context. The HF appears to be crucial for the processing of both allocentric information and encoding different reference frames (contexts), which may be the neural basis of episodic memory.

The nervous system is tasked with activating several memories concurrently without confusing them, creating the need to segregate simultaneously relevant but distinct memories. This chapter focuses on this problem of segregating different, concurrently relevant representations. It examines this question in the context of hippocampal spatial representations, first reviewing behavioral evidence that rats use two concurrent spatial reference frames. It then reviews evidence that the hippocampus is important for the ability to segregate locations in the different spatial frames. Finally, it presents preliminary evidence for a functional grouping of place cell responses, as one of the mechanisms to achieve this segregation of distinct memories.

Empirical data from experimental psychology, primate neurophysiology, and neuropsychological observations of brain damaged patients are the primary generators of experimental hypotheses for functional neuroimaging experiments in spatial neurocognition: the way in which space is mapped from early sensory codes (e.g., retinotopic maps, somatotopic maps) through transformation to higher-order coordinates. This chapter discusses the multicomponent nature of space representation and the existence of several spatial frames (e.g., far as opposed to near space); the distinction between object- and space-based visual cognition; the relationship between space and motion cognition; and the modulation of spatial representation and perception through attentional mechanisms.

Navigation appeared early in the evolution of animals and occurs in all mobile species. The vast array of navigational capabilities in various species poses a challenge to describe and understand these capabilities. This chapter proposes a unifying framework to formulate common underlying principles that operate across different taxa. This navigation toolbox contains a hierarchy of representations and processes, ranging in complexity from simple and phylogenetically old sensorimotor processes, to the formation of navigational “primitives” (e.g., orientation or landmark recognition) to complex cognitive constructs (e.g., cognitive maps), culminating in the human capacity for symbolic representation and language. Each element in the hierarchy is positioned at a given level by virtue of being constructed from elements in the lower levels and having newly synthesized spatial semantic contents in the representations that were not present in the lower levels. In studying individual species, the challenge is to determine how given elements are implemented in that species, in view of its particular behavioral and anatomical constraints. The challenge for the field as a whole is to understand the semantic structure of spatial representations in general, which ultimately entails understanding the behavioral and neural mechanisms by which semantic content is synthesized from sensory inputs, stored, and used to generate behavior.

Space is an important supramodal feature for linking inputs from different sensory modalities. This chapter reviews recent findings demonstrating that the visual modality is essential for the setting-up of spatial representations used as a default for multisensory interactions in later life. Thus, people blind from birth show no or a markedly reduced multisensory binding based on spatial features. By contrast, late blind people’s default spatial coordinate systems are indistinguishable from those of sighted individuals. Possible consequences for crossmodal plasticity are discussed. Finally, people born totally blind whose sight has subsequently been restored, show a marked impairment in audio-visual integration. Results using the visual deprivation approach as a retrospective developmental approach to study the development of multisensory functions thus suggests that there are sensitive or even critical periods during which normal visual input must be available in order to allow for the development of full multisensory capabilities.

The hippocampal system provides a beautiful example of how different classes of neuronal network in the brain work together as a system to implement episodic memory, the memory for particular recent events. The hippocampus contains spatial view neurons in primates including humans, which provide a representation of locations in viewed space. These representations can be combined with object and temporal representations to provide an episodic memory about what happened where and when. A key part of the system is the CA3 system with its recurrent collateral connections that provide a single attractor network for these associations to be learned. The computational generation of time, encoded by time cells in the hippocampus, is described, and this leads to a theory of hippocampal replay and reverse replay. The computational operation of a key part of the architecture, the recall of memories to the neocortex, is described.

This chapter discusses the frame-of-reference concept, arguing that this concept has been the subject of considerable confusion in cognitive and neuroscientific research on spatial representation. In particular, it argues that two distinct questions about frames of reference in the brain have been massively conflated and that the dominant empirical method for probing reference frames speaks to only one of these questions. Finally, it suggests that both questions can be addressed empirically.

This chapter poses the central question of the book: How can the absence of approximately twenty-five genes in people with WS cause the unusual cognitive profile of severely impaired spatial cognition together with fluent and well-structured language? After presenting a description of this hallmark cognitive profile, the chapter argues that answering this question requires considering three more general issues. First, the complexity of the causal chain between genes and cognition requires that we clearly specify the target level of explanation—in this book, the chapter targets the level of cognition. Second, the chapter argues that the highly specialized nature of human spatial-cognitive architecture plays a crucial role in explaining any developmental outcomes. Third, the chapter argues for the importance of considering normal developmental trajectories in the emergence of spatial cognitive systems in people with WS. The chapter closes with a plan for the remaining chapters.

This chapter concludes by proposing that the unusual profile of people with WS can best be understood by considering the rich cognitive structures inherent in human spatial representational systems, and their modulation through variation in developmental timing. Contrary to the original description of the cognitive profile of people with WS, the chapter suggests that the profile is remarkably similar to that of much younger normally developing children, both for space and language. This outcome can be understood as the product of highly specialized systems of cognition that emerge along an abnormal developmental timeline. Thus missing genes do not directly cause abnormalities in specific cognitive systems; rather, they target developmental mechanisms that underlie the emergence of all specialized cognitive structures. This hypothesis accounts for a broad range of evidence on the spatial and linguistic profile of people with WS, and sheds new light on how normal development of space and language emerge.

This chapter lays out one approach to describing the inferential problem encountered when integrating multiple different cues that may arise from many different objects. By switching representations from a set of discrete single-valued cues to a spatial representation based on attribute and cue “maps,” it was possible naturally to model observers' behavior in some simple multiobject and multicue settings, and provide a natural, tractable approach to approximation within these settings. But while effective in these simple cases, the framework is still far from providing a complete description of perceptual inference and integration in cluttered scenes. The framework developed here works best when the cues used for inference are inherently localized in space (in the visual case) or with respect to some other dimension important for determining grouping.

One of the questions currently vexing researchers is whether peripersonal space is better conceptualized as being extended or as being projected following tool use? It may turn out that the answer to this question depends on what exactly the tool user must do with their tool. An equally important, if putatively orthogonal, issue concerns whether the effects of tool use are best conceptualized in terms of an attentional modification (i.e., prioritization) of a certain region of space (where the tool is being, or has been, used to perform an action) versus a change in spatial representation. While there is now an extensive body of evidence documenting tool use in a variety of animals, including recently in invertebrates, the focus of this chapter is primarily on the evidence collected from studies of tool use in humans and other primates. In particular, it reviews those studies that have used the cross-modal congruency task in order to investigate how the perception of peripersonal space changes during tool use. It also briefly compares these results to those that have emerged from neuropsychological research with clinical patients suffering from crossmodal extinction (i.e., from an impaired ability to report a stimulus on the contralesional side when it is presented at the same time as an ipsilesional stimulus).

This chapter evaluates one example of the link between the underlying spatial representation and the external information that is presented in the previous chapters, addressing the developmental changes that take place. It focuses on the features of maps that affect learning, on spatial perspective, on the use of location information to assist identification, on the representation of the spatial features that give rise to spatial categories for projective relations such as above and below, and on the relation between linguistic features and the spatial features that define containment and support categories. Within each section, the issues that offer a useful contribution to researchers in adult spatial cognition and issues from the adult spatial cognition literature that could be profitably examined developmentally are highlighted.

This chapter examines Berkeley’s theory of vision. He endorsed the essentials of Locke’s account of visual depth perception while deepening and extending it beyond anything contemplated by Locke. The core idea common to both is the need for “the Experience that what affects his touch so or so, must affect his sight so or so”. The synthesis of visual spatiality, Berkeley’s theory of spatial representation, the tactual bases of spatial imagination, the phenomenology of vision, the formal multiplicity of vision, the visual language of spatiality, and objects as chapters in the volume of nature are discussed.

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.

This chapter provides background on the genetic profile of people with WS, followed by a review of what is known about the possible structural and functional brain bases for the spatial deficit. Current findings indicate regions of abnormal structure and function in the WS brain that include parts of the dorsal stream, specifically, areas of the parietal cortex, as well as the hippocampus and adjacent regions. This review is followed by a detailed analysis of the hallmark block construction task, emphasizing the many cognitive capacities that are engaged when people carry out such tasks. We close the chapter by discussing the hypothesis that the WS spatial deficit may be characterized by strength in those spatial functions normally engaging the ventral stream of the visual system, and weakness in those functions normally engaging the dorsal stream. This hypothesis is evaluated and progressively modified in Chapters 3, 4, and 5.