Localisation of Function in the Brain

9 Key excerpts on "Localisation of Function in the Brain"

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  The Cambridge Handbook of Cultural-Historical Psychology

  • Anton Yasnitsky, René van der Veer, Michel Ferrari(Authors)
  • 2014(Publication Date)
  • Cambridge University Press

    (Publisher)

  In the case of language, for instance, one localization is responsible for articulating speech and another localization for understanding speech. The lan- guage function depends on functioning of such localizations and brain structures that connect them. Third, there is also another principle that is less acknowledged: namely, localization of functions is not fixed. Persons with early brain damage to the left hemisphere, for instance, may rely on right hemispheric localizations in 326 aaro toomela language functions; the same right hemispheric localizations are not involved, and will not be involved even after the recovery period, if the damage occurs in an adult. Vygotsky, who formulated the principles that underlie cultural-historical neuro- psychology, also proposed that “every specific function is never connected to the activity of any one center, but always is a product of integrative activity of strictly differentiated and hierarchically connected one to another centers” (Vygotsky, 1982b, p. 170). Vygotsky went further with the principles underlying localiza- tion of the functions. He suggested, next, that mind should be understood as a whole. Therefore the relationship between localized brain damage and cognitive dysfunction is complex: (1) In case of any localized brain damage (aphasia, agnosia, apraxia), all other functions, which are not directly related to the damaged region, will suffer in a specific way and there is never uniform decrease of the functioning . . . (2) One and the same function, not related to the damaged region, will also suffer in an absolutely peculiar, absolutely specific way in case of different localizations of the damage and does not reveal the same focus in case of different localizations.

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  Language Communication and the Brain

  A Neuropsychological Study

  • Mariusz Maruszewski, Grace W. Shugar(Authors)
  • 2017(Publication Date)
  • De Gruyter Mouton

    (Publisher)

  Although with some simplification, the localization issue can be reduced to two opposing theories, one postulating localization and the other denying this idea. The former conception posits a brain that is functionally differentiated, or composed of structures that serve different roles in controlling the activities of the organism. In the original narrow version (the psychomorphological conception), it was contended that, for every function of the organism, there is a corresponding distinctive centre, or organ, in the brain. Present-day proponents of the localization theory reject the existence of such centres; their more moderate views stress only that particular brain structures perform separate and distinct physiological functions necessary for the normal course of the organism's many different activities. Functionally differen-tiated, these structures interact dynamically to ensure each such activity. In its contem-porary version this conception is labelled the dynamic theory of functional localiza-tion. 1. EARLY OBSERVATIONS OF SPEECH DISORDERS FOLLOWING CEREBRAL DAMAGE 19 The opposing theory of anti-localization, in its most extreme version, denies any localization whatsoever as to the higher functions of the organism. The cerebrum is viewed as an undifferentiated and equipotential structure in respect to function. Higher functioning is the outcome of the activity of the entire brain tissue. It then follows that the search for centres, or structures with more or less fixed functions, is foredoomed to failure. It is clear that acceptance of one or the other of these positions has crucial signifi-cance for the problem we are tackling; each entails radically different consequences in any undertaking to elucidate the cerebral mechanisms of speech. Let us repeat that this controversy has had a determining effect upon both the historical growth of knowledge and the present state of thinking in this domain.

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  Psychobiology Behavior From a Biological Perspective

  • James McGaugh(Author)
  • 2012(Publication Date)
  • Academic Press

    (Publisher)

  The ideas of this worker combine the principles of narrow localization with those of equipotentiality.* VI. THE LOCALIZATION O F MEMORY The controversy between the localizationists and the antilocalization-ists dealt with the attempt to identify complex mental processes or psy-chological concepts with the material structure of the brain. The problem of localization of memory was a particular aspect of the more general question of functional localization. Much of the evidence on which the-ories of memory localization were based came from studies of conditioned responses in which a sensory stimulus came to elicit a new motor move-ment after a conditioning procedure. It was assumed that the sensory stimulus affected a particular sensory region of the brain, that the condi-tioned movement was controlled by the motoric regions of the brain, and that conditioning established a new pathway between the sensory region and the motor region so that the sensory stimulus could influence the activity of the motor region. Generations of physiological psycholo-gists have attempted to localize this pathway mediating the new influence of the sensory stimulus on the motor system by destroying various re-gions of the brain. The failure of such ablation studies has been thor-oughly catalogued by Lashley in his paper entitled In Search of the Engram (1950a). Strict correlation of structure with function is difficult even with re-spect to such relatively species-constant characteristics as sensory input and motor output regions. The variability of the responses elicited by stimulation of the motor system has already been mentioned. Evidence * I wish to acknowledge my indebtedness to A. R. Luria for his excellent review in Higher Cortical Functions in Man (1966) from which I have borrowed heavily in summarizing the historical development of the localizationist and antilocaliza-tionist positions.

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  Selected Writings of A.R. Luria

  • Michael Cole(Author)
  • 2017(Publication Date)
  • Routledge

    (Publisher)

  Vygotsky's ideas radically altered our view of the nature and structure of mental processes. Fixed and immutable "mental functions" were transformed into complex and mobile functional systems that change during development; psychology emerged from its constricting naturalistic boundaries and became the science of the social formation of natural phenomena.

  One question, however – perhaps the most essential one –remained open: How is the material substratum to be understood? What conceptions of the working of the brain should underlie our view of the material bases of mental activity?

  The problem of localizing mental functions in the cerebral hemispheres (and the question of the cerebral bases of mental activity was formulated in precisely this way) underwent a period of acute crisis in the 1920s, reflecting to a large extent the general crisis in psychology. On the one hand, neurology continued to assert its naive ideas of the localization of complex mental functions in limited areas of the cerebral cortex – ideas originally crystallized in the great discoveries of the 1870s. On the basis of the simplified views of mental functions then current in psychology, neurologists assumed that in addition to the cortical sensory and motor "centers," analogous centers could be found for more complex mental processes. As a result of the writings of Lissauer, Henschen, and Kleist, the idea of "perceptual centers," "calculational centers," and "conceptual centers" in the cerebral cortex did not seem the least bit extraordinary.

  Naturally enough, however, these views of restricted localization gave rise to serious doubt. Aware of the complexity of human higher mental processes and taking into account the well-known clinical fact that they could be disrupted by injuries in widely varied locations, many neurologists assumed that complex forms of mental processes were the result of the activity of the brain as a whole. Some of these authors, adhering to the holistic viewpoint (Monakov, Grunbaum), under the noticeable influence of the Würzburg school of psychology, were indifferent to all attempts to examine more closely the cerebral apparatuses connected with higher forms of mental activity. Others, supporting Gestalt psychology (K. Goldstein), tried to construct a hypothesis of an excitation structure evenly distributed throughout the cortex and to see the basis of complex forms of human mental activity in these featureless "structural" processes. While accepting a restricted localization of elementary physiological processes in limited areas of the cortex, they rejected in practice all concrete analysis of the critical zones that take part in the execution of complex forms of human mental activity. "Revolving in a vicious circle of structural psychology," wrote Vygotsky, "examination of the localization of specifically human functions vacillates between the poles of extreme naturalism and extreme spiritualism" (loc. cit. P. 386).

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  Foundations of Cognitive Processes

  • Robert W. Thatcher, E. Roy John(Authors)
  • 2021(Publication Date)
  • Routledge

    (Publisher)

  Fig. 9.3 . Note the localization of “subjective experience.”

  FIG. 9.3 A typical chart of cerebral localization of functions, from a text published in 1934 (Kleist, 1934).

  II. The Anti Localization 1st Viewpoint

  Throughout the period in which the localizationists were developing their beliefs and the evidence on which those beliefs were based, a diametrically opposed school of thought was marshalling its own arguments. An early representative of this was A. Haller who, writing in 1769, acknowledged that different parts of the brain might well be involved in different functions, but postulated that the brain acted as a single organ composed of parts of equal importance. Damage to a single region can cause disturbance of various functions, and many of these disabilities can be compensated for by the remaining tissue. In what is probably the earliest piece of experimental work supporting the antilocalizationist position, Flourens (1824) showed about the same degree of recovery of function in birds regardless of which part of the brain was damaged. He concluded that the cortex acted as a homogeneous entity. Some years later (1842), he showed that reversing flexor and extensor innervation of the wing in a cock could be compensated, and argued that this was evidence for equipotentiality of function of different regions of the brain. Further experimental studies of a similar sort were done by Goltz between 1876 and 1881. After extirpation of various parts of the cerebral hemispheres, Goltz (1884) reported that dogs showed a variety of marked disturbances of behavior, using general responses as a measure. These disturbances gradually disappeared. The functions were restored, leaving only slight awkwardness. These observations led to the idea that any part of the brain could be associated with ideas and thought, and the defect observed after brain damage was solely related to the size of the lesion.

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  Perception, Realism, and the Problem of Reference

  • Athanassios Raftopoulos, Peter Machamer(Authors)
  • 2012(Publication Date)
  • Cambridge University Press

    (Publisher)

  On Lashley’s view, it was a mistake to refer to specific cognitive functions performed in these brain areas. Although lesion studies contributed to answering Lashley, further successes in localizing information processing in the brain relied heavily on the development of techniques for recording action potentials from individual neurons and correlating the increased generation of action potentials in particular neurons with the presentation of specific stimuli. After Hubel and Wiesel (1962, 1968) showed that the cells in the occipital cortex that Munk had viewed as the locus of visual processing seemed only to differentiate edges, they and other researchers looked more anteriorly and identified areas in temporal and parietal cor- tex responsive to other features of visual stimuli, including motion, color, shape, and object identity. I have analyzed the history of localizing different steps in processing visual inputs in different cortical regions elsewhere (Bechtel 2008). What is important for present purposes is the conception of brain process- ing assumed in this research. The assumption is that the brain contains Cognitive operations in dynamically active brains 265 a mechanism for processing visual inputs and that the goal was to dis- cover this mechanism. A mechanism for these purposes is a system that consists of distinguishable parts that perform specific operations which are organized to generate the phenomenon of interest (Bechtel and Richardson [1993] 2010; Bechtel and Abrahamsen 2005; Machamer et al. 2000). Differentiating parts and operations required the development of appropriate research techniques to decompose the brain structurally and functionally. Using staining techniques to differentiate the distribution of neurons in the cortex, for example, Brodmann ([1909] 1994) and his con- temporaries developed maps of different brain regions early in the twen- tieth century.

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  Central Nervous System Tumours of Childhood

  • Eddy Estlin, Stephen Lowis(Authors)
  • 2005(Publication Date)
  • Mac Keith Press

    (Publisher)

  21 AN OVERVIEW OF CEREBRAL FUNCTIONING AND ITS APPLICATION IN THE DEVELOPING BRAIN Andrew Curran This chapter aims to provide a readily understandable overview of the mechanisms of how basic functions, such as memory and the emotional content of thoughts, are now believed to work. The aim is to build a picture of brain functioning that allows the reader to place a tumour in any position in the brain and be able to have some idea of the impact that the tumour, surgical removal and radiotherapy will have on cognitive and emotional functions. The first part outlines normal functioning of the brain, with particular reference to the key anatomical structures central to this functionality. Part two describes how structures in the developing brain gradually mature to integrate emotional perception into our memories. The penultimate section focuses on the effects of stress on the developing brain and reinforces the need for sensitive handling of children undergoing stressful experiences. The final section looks at the hemispheric lateralization of functionality. In all fields of medicine, but especially in the care of children, the understanding of how the brain works, and especially the importance of emotional health in allowing the individual to achieve their maximal potential must, I believe, always be paramount in our thoughts. The normal brain T HE R EPTILIAN B RAIN The control of sophisticated structures, such as the bodies of multicellular living organisms, requires coordination and control beyond that seen in simpler organisms. A unified ‘master control system’ to govern these activities in lesser systems is provided by the spinal cord, brainstem and corpus striatum (Fig. 21.1), the so-called reptilian brain, in higher organisms. MacLean (1990) has described this as the first step towards the “triune brain”, the ultimate expression of which is seen in modern man.

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  Of Thoughts And Words: The Relation Between Language And Mind - Proceedings Of Nobel Symposium 92

  The Relation Between Language and Mind

  • Sture Allen(Author)
  • 1995(Publication Date)
  • ICP

    (Publisher)

  As Tor Norretranders has pointed out, professional excellence may be the extreme example of automated, non-conscious, feed-forward performance. Summing Up Beginning with the study of patients with brain injury we have gradu-ally acquired a preliminary understanding of the manner in which language might be implemented in the human brain. Uncertainties have surrounded this understanding because brain injuries in humans vary from one individual to another, and it is never certain whether the function lost through injury represents the function of the area damaged. The pace of our understanding has been greatly accelerated by the acquisition of new brain imaging tools permitting us to view the activity of the normal human brain as language tasks are being per-formed. These imaging techniques, coupled with careful task design is guided by the principles of cognitive science, now permit us to dissect the basic mental operations underlying our behavior and relate them to specific circuitry within the normal human brain. The brain imaging studies of language so far performed strongly support the hypothesis that elementary operations forming the basis of cognitive analysis of human tasks are strictly localized. A glance back at Figure 4 reveals that, as we undertake reading tasks, extensive areas of the brain are recruited to assist in the performance of these tasks. Although we can begin making statements about the roles of such groups of areas (i.e., brain circuits), it remains for further studies to determine the more basic mental operations to be assigned to the in-dividual brain areas within a given circuit. Our studies of words give some indication of the manner in which such an analysis might pro-ceed. This information, coupled with studies of patients with brain injury, guided anew by information from normals, and more basic studies in laboratory animals using a variety of sophisticated tech-niques, bode well for our future understanding of human brain function

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  Neuropsychology After Lashley

  Fifty Years Since the Publication of Brain Mechanisms and Intelligence

  • Jack Orbach(Author)
  • 2018(Publication Date)
  • Taylor & Francis

    (Publisher)

  13 Localization and Distribution of Function in the Brain Karl H. Pribram Departments of Psychiatry and Psychology Stanford University School of Medicine

  Introduction

  Throughout his research career, Karl Lashley remained puzzled by the relationship between brain, behavior, and experience. On one hand, his experiments showed the brain to be put together with exquisite anatomical precision, which was to some degree reflected in the separation by behavioral function of the several sensorimotor systems and even regional differences within the so-called association areas. On the other hand, results of other experiments and observations made it clear that engrams, memory traces, could not be localized and that perceptual images and motor patterns displayed constancies and equivalences for which it was difficult to conceive any permanent “wiring diagram.” Lashley is best known for his continuing attention to these nonlocalizable aspects of brain function that he formalized in the laws of mass action and equipotentiality. But it should be remembered that these aspects were puzzling to Lashley in large part because he was so keenly aware of the anatomical precision of the connectivity that gave rise to nonlocal characteristics in function. Had the brain been shown to be essentially a randomly connected network (as was so often assumed by those then working in the field of artificial intelligence), the problem might not have loomed so insurmountable.

  In this chapter I present data that fill out a theoretical frame that was proposed by Lashley as a possible resolution of the localization/nonlocalization puzzle. These data have accumulated during the quarter century that has intervened since his last paper. The data have been gathered without reference to the frame, and the frame itself was derived, not from brain-behavior studies, but from the problems posed by morphogenesis during embryological development: Structural theories based on the principle of chemical gradients and resonances that “tune” specific locations in cytoplasm as inductors for organelles have been influential in embryology since before the turn of the century (see, e.g., Jacques Loeb, 1907; and Paul Weiss, 1939). In 1906, Goldscheider suggested that the structures of perception and memory might be similarly constructed by resonances among wave fronts created by sensory inputs in brain, especially cortical, tissue. In 1942, Lashley adopted this view as an alternative both to Köhler’s field theory and to a localizationist view in which one percept or engram is matched to one neuron or neuron assembly. Lashley was never satisfied with this adoption because he could not envision the specific mechanisms that would give rise to resonant (and interfering) wave fronts in brain tissue and, equally important, how these, in turn, might be responsible for the structures that comprise perception and engram. He nonetheless held to the view that neither field nor localization (as, e.g., in the sophisticated development of Hebb, 1949) could account for the complex relationship between brain anatomy and phenomenal experience or could deal adequately with the encoding of memory.

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