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Making Maps and Forming Plans

Carolyn Price

in Functions in Mind: A Theory of Intentional Content

This chapter examines a system that is capable of a rather more sophisticated form of spatial representation, particularly a system that enables an organism to find its way about by forming a ... More

This chapter examines a system that is capable of a rather more sophisticated form of spatial representation, particularly a system that enables an organism to find its way about by forming a topographic map of the surrounding environment. It discusses a topographic mapping system and suggests that it is able to identify particular places in a way that is quite distinct from the capacity to keep perceptual track of them. The chapter also evaluates a claim that an organism that possesses a topographic mapping system must be able to represent itself.Less

Map formation

David J. Price and David J. Willshaw

in Mechanisms of Cortical Development

All neurons in the mature nervous system are mapped onto the neurons to which they connect; and therefore, understanding how neural mappings are achieved could be considered synonymous with ... More

All neurons in the mature nervous system are mapped onto the neurons to which they connect; and therefore, understanding how neural mappings are achieved could be considered synonymous with understanding how every aspect of the connectivity of the nervous system is established. This chapter discusses the development of topographically ordered maps of connections, hypotheses for map formation, the development of topographic maps in non-cortical systems, rhe role of fibre ordering in map-making, cytodifferentiation hypothesis, neighbour matching hypothesis, induction of specificity hypothesis, timing hypothesis, development of topographic maps in cortical systems, thalamo-cortical projection and whether the cortical map is specified prior to innervation, mapping to specific cortical areas, the development of callosal and ipsilateral corticocortical projections, the development of feature maps in the visual system, development of geniculate projections to the visual cortex, the effects of neural activity (especially with respect to functional deprivation), models for map-making, models for the development of topography, models based on chemoaffinity, and models for the development of cortical feature maps.Less

The Material Culture of Printing

Klaus Hentschel

in Mapping the Spectrum: Techniques of Visual Representation in Research and Teaching

This chapter discusses the material culture of printing spectra in the 19th century. The social setting of print experts, their wages, and total numbers in various countries (especially France, ... More

This chapter discusses the material culture of printing spectra in the 19th century. The social setting of print experts, their wages, and total numbers in various countries (especially France, Germany, England and the USA) are also taken into consideration. Photomechanical printing techniques widened the possibilities and deeply changed the practice and economy of spectrum mapping, but only in the late 19th century. A frequent transfer of skills from topographic map-making to spectrum map production is revealed. The chapter closes with a section on the economy of the printing trade.Less

Ethologically Relevant Movements Mapped on the Motor Cortex

Michael S. A

in Primate Neuroethology

This chapter reviews evidence that motor cortex in primates is not organized according to topographic maps related to the body surface, but is organized according to species-typical motor behavior. ... More

This chapter reviews evidence that motor cortex in primates is not organized according to topographic maps related to the body surface, but is organized according to species-typical motor behavior. Microstimulation with behaviorally relevant time courses evokes basic movements such as bringing food to the mouth, climbing, or defensive responses. It is argued that primate motor cortex serves as an interface functionally specialized for producing species-typical actions.Less

Principles of Topographic Analyses for Electrical Neuroimaging

Murray M. Micah, Marzia De Lucia, Denis Brunet, and Christoph M. Michel

in Brain Signal Analysis: Advances in Neuroelectric and Neuromagnetic Methods

This chapter presents a new approach to topographic mapping using reference-independent spatial information in high-density electrode montages, and analyzes the pitfalls and limitations of analyzing ... More

This chapter presents a new approach to topographic mapping using reference-independent spatial information in high-density electrode montages, and analyzes the pitfalls and limitations of analyzing event-related potential (ERP) voltage waveforms due to their being dependent on the choice of the reference electrode(s). It reports the methods for identifying and quantifying topographic modulations. The chapter shows that the analysis used for identifying the periods of topographic stability within and between experimental conditions serves to determine the sequence, duration, and explanatory power of the “letters” in the ERP. It suggests that information-rich analyses can be easy to use and interpret.Less

Cortical Neurophysiology in the 1950s

David H. Hubel

in Brain and Visual Perception: The Story of a 25-year Collaboration

Neurophysiology has changed radically since the late 1950s. In the cerebral cortex, early work was mainly concerned with localization of function, essentially a type of neuroanatomy that used ... More

Neurophysiology has changed radically since the late 1950s. In the cerebral cortex, early work was mainly concerned with localization of function, essentially a type of neuroanatomy that used clinical neurology and electrical stimulation and electrical recording. By the late 1950s, the topographic maps of the primary and secondary visual, auditory, and somatosensory receiving areas had been delineated electrically, in humans, cats, and monkeys. In vision, the most important topographic mapping had been done back in 1941 by Wade Marshall and Samuel Talbot, at Johns Hopkins. In the mid-1950s, the first single-cell studies of the visual cortex came from a group led by Richard Jung and his collaborator Günter Baumgartner in Freiburg. In the 1950s, most of the single-cell recordings from the sensory cortex were concerned with topography.Less

Naming and Mapping

in From Squaw Tit to Whorehouse Meadow: How Maps Name, Claim, and Inflame

This chapter discusses the issue of naming and mapping various cartographic insults, some of which got onto the area's government topographic map due to the area's past and some pleasant surprises. ... More

This chapter discusses the issue of naming and mapping various cartographic insults, some of which got onto the area's government topographic map due to the area's past and some pleasant surprises. Most pejorative place names, however, have less noble origins, and as numerous examples illustrate, the search for a suitable replacement name can be surprisingly contentious. A state board can approve a change, but if the U.S. Board on Geographic Names does not buy it, the new name never appears on federal maps, which include the large-scale topographic maps by the U.S. Geological Survey (USGS)—used not only by scientists and hikers but also by companies that make atlases, guidebooks, indexed street maps, and tourist maps. If the USGS does not pick up the change, commercial mapmakers will probably ignore it as well.Less

Mount Taylor Places in Time and Space

Asa R. Randal

in Constructing Histories: Archaic Freshwater Shell Mounds and Social Landscapes of the St. Johns River, Florida

Cross-culturally, the arrangement of residential and ceremonial architecture can reveal how communities were composed and how they integrated elements of the past within more recent landscapes. Shell ... More

Cross-culturally, the arrangement of residential and ceremonial architecture can reveal how communities were composed and how they integrated elements of the past within more recent landscapes. Shell mounds are the most visible evidence of Mount Taylor occupation on the St. Johns River. Detailed study and description of these places has been seriously hampered by destructive twentieth-century land use practices, such as the mining of mounds for road aggregate. Chapter 5 examines the range of variation in Mount Taylor shell sites in time and space by synthesizing and interpreting historic, pre-mining observations; aerial remote sensing data, such as photographs and LiDAR; and modern excavation data. The author explains how, by placing these data into a GIS, topographic maps can be generated, which enable a historical typology of shell site arrangement and location through time.Less

Development and Evolution of Speech Sound Categories: Principles and Models

Gert Westermann

in Evolution of Communicative Flexibility: Complexity, Creativity, and Adaptability in Human and Animal Communication

This chapter uses a self-organizing map approach to simulate learning of the human vocal system through babbling, and deals with the constraints and mechanisms at work in the development and ... More

This chapter uses a self-organizing map approach to simulate learning of the human vocal system through babbling, and deals with the constraints and mechanisms at work in the development and evolution of phonetic repertoires to establish a stable system of discrete speech sounds that can form the basis of a flexile communicative system. It shows that the principle of mutually constraining topographic maps provides possible explanations of phenomena in areas as diverse as speech processing, word learning, categorization, and language evolution. The chapter suggests that the mirror neurons are one piece of evidence of the correlation-based integration of neural populations across domains.Less

Purging Pejoratives

in From Squaw Tit to Whorehouse Meadow: How Maps Name, Claim, and Inflame

This chapter explores the conflicts and conundrums that arise in removing objectionable names from maps. To address the extent of the problem of objectionable names, the author compiled a list of ... More

This chapter explores the conflicts and conundrums that arise in removing objectionable names from maps. To address the extent of the problem of objectionable names, the author compiled a list of derogatory terms and queried the Geographic Names Information System (GNIS) to find which ones might be found on topographic maps. Among groups vulnerable to cartographic insult, Italian Americans get off lightly. GNIS turned up 51 official names and 10 variants based on guinea—an anti-Italian pejorative that also denigrates people of mixed American-Indian and African-American ancestry. German and Polish Americans have even less cause for complaint. A query to GNIS found only eleven cases of kraut and six of Polack. Non-ethnic white Americans are not spared, at least not in the Southwest, where gringo has derogatory connotations. Derived from the Spanish word for Greek, gringo once referred to anyone speaking a strange language.Less

Neuroscience Overview

Patricia S. Churchland and Terrence J. Sejnowski

in The Computational Brain

This chapter provides an overview of the “neuroscience” component of the “computational neuroscience” synergy. It begins with a discussion of three ideas about levels in nervous systems: levels of ... More

This chapter provides an overview of the “neuroscience” component of the “computational neuroscience” synergy. It begins with a discussion of three ideas about levels in nervous systems: levels of analysis, levels of organization, and levels of processing. Levels of organization are essentially anatomical, and refer to a hierarchy of components and to structures that comprise these components. Levels of processing are physiological, and refer to the location of a process relative to the transducers and muscles. Levels of analysis are conceptual, and refer to different kinds of questions asked about how the brain performs a task. The chapter proceeds by considering seven categories of structural organization in nervous systems: systems, topographic maps, layers and columns, local networks, neurons, synapses, and molecules. It concludes by presenting a short list of brain facts.Less

The pathways for action

Ray Guillery

in The Brain as a Tool: A Neuroscientist's Account

Early nineteenth-century studies demonstrated, on the basis of clinical, experimental, and anatomical evidence, that a motor pathway, the corticospinal or pyramidal tract, passes from a specific area ... More

Early nineteenth-century studies demonstrated, on the basis of clinical, experimental, and anatomical evidence, that a motor pathway, the corticospinal or pyramidal tract, passes from a specific area of the cortex, the precentral motor cortex, to the brainstem and spinal cord. The motor cortex can be seen as a topographic map of the movable body parts, and damage to the cortex or pathways produces correspondingly localized paralysis. However, there are a great many other pathways that link other areas of the cortex to parts of the brain active in the control of movements. These still play a puzzling role in the standard model where the control of movements focuses on cortical contributions to voluntary movements by the corticospinal pathways.Less

Cerebral Cortex: Basics

James A. Anderson

in After Digital: Computation as Done by Brains and Machines

Hardware matters. The neural organ largely responsible for cognition is the cerebral cortex of mammals. Cortex is a thin two-dimensional layered structure arranged with on the order of a few hundred ... More

Hardware matters. The neural organ largely responsible for cognition is the cerebral cortex of mammals. Cortex is a thin two-dimensional layered structure arranged with on the order of a few hundred interconnected regions that seem to be specialized for particular operations. Regions often show topographic organization. Early vision displays an interestingly distorted topographic map of the retinal input, audition has a topographic map of frequency, and there is a distorted map of the body surface on the somatosensory areas. Information in cortex is not “processed” with an orderly flow from raw input data to a final conclusion but seems instead to send information both backward and forward so sensory input and learned information work together for a consensus analysis. Relative to body size, a bigger brain is a better brain. The most common cell types are variants of pyramidal cells with pronounced lateral interconnections.Less