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Neuropsychology: 7330. Prof. R. D. Whitman. Introduction. For millennia, probably since the emergence of consciousness and symbolic thought humans have been concerned with a set of problems some of which are reducible to the mind-brain problem
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Neuropsychology: 7330 Prof. R. D. Whitman
Introduction • For millennia, probably since the emergence of consciousness and symbolic thought humans have been concerned with a set of problems some of which are reducible to the mind-brain problem • The key original issues in philosophy and psychology are still the focus of attention in neuropsychology. • The mind body problem (Descartes at least) • Consciousness • Perception • Thought (including language, memory, problem solving) • Meta-Issues • Reductionism - neuropsychologists assume psychoneural equivalence at some level. • Localization versus equipotentiality Neuropsychology Introduction
First Use of the term “Neuropsychology” • Neuropsychology: Derives from various Greek words to amount to: doctrine of the "nerves" (neurologie) and the soul (psychologie). Now: mind and brain: • The first use of the term “neuropsychology,” is usually attributed to a talk given by Karl Lashley at a 1936 presentation at the Boston Society of Psychiatry and and Neurology, reprinted a year later. Stanley Finger(1994) notes that William Osler used it first in passing, and that Goldstein used it in his 1934 classic. He notes that Lashley cited the Goldstein reference in the same sentence in his talk. As Finger notes, Osler was speaking of brain diseases and mental disorders, whereas Lashley and Goldstein were referring to the study of higher cortical function following brain injury or disease [but were they referring only to higher cortical function following insult? or was Lashley concerned with understanding the relationship between higher cortical function and brain] Finger states that it is largely a clinical field, though there is a “growing” hard core experimental neuropsychology) • Kurt Goldstein later worked with Marianne Simmel, a psychologist who later worked with the neurologists in Chicago who gave Ward Halstead his patients. Neuropsychology Introduction
Other Historical Derivations • Neuropsychology is the body of knowledge and research relating mind and brain. It differs from physiological psychology only in its focus of its attention and, in recent years, it's clinical application. It has historically been interested in higher cortical processes. Thus it is an integration of two of the three basic foci of psychology -- mental processes and a reductionist understanding of these. The third major area of psychological study, the social interactions of persons, is a less touched upon issue for neuropsychology. • Had Sigmund Freud not been distracted by the development of his personality theory he might have made a significant contribution to neuropsychology. He was trained as a neurologist, and had written an excellent monograph (On Aphasia). Project Towards a Scientific Psychology was published posthumously. I believe that it is his most provocative work, and that you cannot understand his personality theory without understanding this. (Several more modern works have reviewed this paper, including an excellent one by Karl Pribram). Donald Hebb (1949) wrote a book discussing a hypothetical way of thinking about cell assemblies which was very similar to Freud’s theories and which clearly predates, at least in concept, modern connectionist theory. Neuropsychology Introduction
Other Historical Derivations • Often used to refer to "higher cortical function" {Luria, A. (1966). Higher Cortical Functions in Man. New York, Basic Books.}. But the distinction between higher cortical functions is not clear: basic sensory processes are mediated cortically and subcortical damage can influence complex intellectual functions. • Only twenty years ago, in the early 1970's there were only two journals, Cortex and Neuropsychologia, specifically dedicated to the study of brain and higher cortical functions. Today it has become a major focus of study with multiple books, specialized books, multiple journals, and multiple professional groups that identify themselves as members of the neuropsychological community. • Historically it has been closely tied with neurology but the special nature of psychology as a science - a science constructed of theories of mental processing and the awareness of the importance of measurement issues and experimental design, and the concept of representation separates neuropsychology from neurology. Whereas neurology contributed to the knowledge of brain and mind in the last century and into the beginning of the present, experimental psychology has been a dominant source for increased knowledge since that time. That is because of the limitations of the casual observations of correlations between brain damage and its effects. Neuropsychology Introduction
Two trends modified neuropsychology: • The first trend is the extraordinary growth of Clinical Neuropsychology. It's advantages are many.. • Its costs are a medicalization of the field, a preoccupation with tests, clinical correlations, and so on - to the exclusion of knowledge of previous research, model building, hypothesis testing, and so on. • BUT, the clinical neuropsychologist today, despite the clinical demands of the specialty are likely to be knowledgeable of changes in the field, to do research and publish, to maintain an active presence in professional associations, to involve themselves with standards in the field, and so on. • Requirements: neuropathology, neuroanatomy, basic understanding of neurochemistry, psychometrics, psychopathology, neuropsychology, and tests as applied to brain damaged populations. The standards set by Division 40 of the American Psychological Association are very appropriate. (Provided) Neuropsychology Introduction
Clinical Neuropsychology has both a theoretical research and an applied tradition • The theoretical research position came first. Clinical Neuropsychology – neuropsychology – Ann Triesman, Teuber, Milner, these were experimental psychologists who took experimental psychology to the clinical population. • Later the applied, largely testing tradition emerged, stimulated by clinical needs following WWI, WWII, and the Korean War. Neuropsychology Introduction
Two trends modified neuropsychology: Trend 1 continued • Current Trends – largely market driven • Emphasis on description of skills/deficits rather than localizing hypotheses • Emphasis on rehabilitation • Behavioral approaches to rehabilitation: money driven • More sensitive behavioral tests • More emphasis on prevention Neuropsychology Introduction
Whitman Bias: • Unfortunately the professionalization of the field may result in a loss of understanding of what made neuropsychology special. Current credentialling approaches are more concerned with neuropsychologists as testers than as theoreticians. Much of the current clinical neuropsychology literature is distracted by clinical cases and issues and models which, rather than providing "nature's experiments" are becoming the focus of attention: -- BUT this trend is counterbalanced by the explosive growth of cognitive neuroscience • What are some of the important questions? • Coding • Consciousness • Perception • Memory • Laterality • Localization of function versus equipotentiality: OR, How does the nervous tissue do various emergent functions. • Plasticity Neuropsychology Introduction
Two trends modified neuropsychology: • Second Trend • Cognitive psychology is, traditionally, more concerned with models than with brain, only recognized the importance of taking brain into account in its models in the past 15 years. Though many of the roots of modern cognitive psychology (pattern perception, I/O psychology (e.g. Donald Broadbent), Neisser's Cognitive Psychology) are broad a good deal of the field has been preoccupied with models of language. Often these researchers have been concerned with dissociating themselves from learning theory (often simplifying it by reference to Skinner, or radical behaviorism). Michael Posner probably deserves credit, more recently, for making the brain a respectable consideration in cognitive psychology. However, most of the credit is probably due to the advances in neuropsychology only recently "discovered" by cognitive psychologists. Only recently one leader in the current "connectionist modeling" movement, Mark Seidenberg, admitted that connectionist models had a vague similarity to learning models but refused parenthood and said that learning only represented a small part of the cognitive domain. He is wrong. And it's too bad he marred an otherwise excellent article with his need to say that. It is a sign of immaturity in a science to dissociate oneself from historical roots. Actually connectionist models are quite like a number of previous approaches - Hebb's cell assemblies (1949), associationistic learning theory, and mathematical learning theory,Gestalt Psychology even, and so on. Neuropsychology Introduction
Interesting phenomenon here: the cognitive psychologists who recently "discovered" neuropsychology for themselves, and even act as though they invented it, often seek special clinical cases to prove their models of how the brain might work. But traditionally it is the other way around = the clinical observation leads to the model which leads to critical experimental tests. Neuropsychology Introduction
Historical Notes Earliest Writings • Craniotomy: 3000 B. C. in pre-Columbian Peru extending to the end of the Inca civilization in the sixteenth century • 2500 B.C. Ebers Papyrus • An archeologist by the name of Smith discovered an Egyptian surgical text written in the "Old Kingdom" about 3000-2500 B. C.. The Papyrus includes about 50 cases. Case No. 22, entitled "Instructions concerning a smash in the temple," reads, in part: • "If thou examinist a man having a smash in his temple, thou shouldest place thy thumb upon his chin and thy finger upon the end of his ramus, so that the blood will flow from his two nostrils...If thou callest to him (and) he is speechless (and) cannot speak, then shouldest say concerning him...he is speechless; (and) he suffers with stiffness in his neck. An ailment not to be treated." Neuropsychology Introduction
Historical Notes • 384-322 B. C. In the time of Aristotle, the brain was viewed as a cooling system for the heart. Democritis and Plato, on the other hand, thought intelligence was located in the brain. • 5 B. C. From the Corpus of Hippocrates we obtain a collection of clinical cases dealing with speechlessness. He also notes that lesions produced contralateral spasms. The loss of speechlessness was attributed, however, to the loss of fluid of the blood vessels. And noted that probing of the tissue on one side could lead to paralysis on the other side. • A. D. 130 -- 200 The next significant physician to touch upon our topic was Galen. In the manner of the heart versus the brain as the center of sensation he employed the experimental method. He seized the heart of an animal with forceps and observed that the animals sensation was still intact and that the animal grew louder in its complaints. On the other hand, when the ventricles of the brain are pressed these abilities are lost...therefore the nervous principle is located in the head. He also made considerable anatomical studies of the cranial nerves and at least correctly identified them as pathways. Neuropsychology Introduction
Historical Notes • During the next 1500 years or so numerous writings in a variety of areas of the world attributed the workings of sensation and cognition to either the tissue of the brain or to the ventricles. (e.g. Vesalius) Then in the 1600's developments in philosophy and increased descriptive anatomy of the brain resulted in more theorizing about mind and brain. However, the search was still for the elusive single seat of mentation. This single seat of thought was located in numerous places. • Descarte located it in the pineal body (1686) • Vieussens and Willis located it in the corpus striatum (1664) • Lancisi in the corpus callosum (1739) • Sir Charles Bell & Fancois Magendie : spinal roots are split into dorsal sensory and ventral motor divisions. Neuropsychology Introduction
Historical Notes • Faculty Psychology • Then a new school of psychology, often referred to as "faculty psychology" emerged, heavily influenced by Scottish psychology (Reid and Stewart). This perspective subdivided the intellectual function into separate, specialized "faculties." [This perspective is emerging again in the work of the popularist, Gardiner and Sternberg (the Yale Sternberg, not the good psychologist)] • Early 1800's. It was Gall, and his student Spurzheim, however, who led the modern movement towards localization. Borrowing heavily from the Scottish and English psychologists (though making modifications where necessary for his purposes) he proposed that the brain consisted of many organs, each subserving a particular faculty. This solution solved, as Krech (1962) points out, a particular ego function for Gall. He was often beaten out in school by others who he felt could memorize better than he. He then made the observation ....kid with bug eyes and good memory, (Emanuel Swedenborg (1688-1772) actually had done a lot of this theorizing earlier than Gall but he turned to religion and his neurological theorizing was buried until the late 1800’s) Neuropsychology Introduction
Gall’s Four Assumptions: • Moral and intellectual faculties are innate • Their exercise and manifestation depend on cerebral structures • The brain is the seat of all faculties, tendencies, feelings • The brain is composed of as many particular organs as there are faculties, tendencies and feelings Neuropsychology Introduction
Historical Notes • And this created a debate (which often recurs) between localizationism and anti-localizationists. • Period of 1861 - 1875.. rapid growth in neurology, anatomy, physiology, Broca, Bouillard, Meynert, Wernicke, and so on. Language, hemispheric dominance • Fritsch and Hitzig, stimulation of motor cortex. • At that time the two opposing approaches can be exemplified by Wernicke's neural connectionism and Wundt's associationism. (Again interesting that modern cognitive "connectionists" wish to dissociate themselves from associationism) Neuropsychology Introduction
Historical Notes • A second major debate : • Equipotentialism (Flourens) versus localizationism (Gall) The debate again flourished as a result of Lashley's (1950) search for the engram. • Hughlings Jackson: Hierarchical Organization. • Much of this history is clinical cases with correlated deficits leading to localization of function versus thinking, Neuropsychology Introduction
A second major trend was the development of the Neuron Theory, and its subsequent proposals about neuronal connections, neuronal nets, and so on. • Golgi, Ramon y Cajal (1890's), • A conceptualization of this... Wernicke, long known by neuropsychologists and recently discovered by cognitive psychologists....the "centers" somehow retain representations of the information reaching them, over time these representations (or images) integrate the information via the paths connecting the centers. This led to the "diagram makers", again similar to tendencies of early cognitive approaches. Disconnection syndromes: later made Geshwind Neuropsychology Introduction
Then trend towards localization • Broca’s “tan tan” • Lateralization of functioning: does the right hemisphere have language...Broca, and more recently Gazzaniga. • Agnosias (visual agnosia: Freud, 1891) Neuropsychology Introduction
MODERN PERIOD: • Karl Lashley: Mass Action and Equipotentiality • World Wars • Vigotsky, Simmel, Goldstein • Von Monakow's "diathesis" • Teuber, double dissociation • Penfield and Jaspers neurosurgery • Psychometrics and statistical evaluation (Bessel, Galton, Binet) • Brenda Milner: Rasmussen, Wada, Penfield, lateralization after removal of temporal lobes: Doreen Kimura, • Classification • Discovery of fluent and non-fluent articulatory aphasia (rather than a normal distribution of fluency) • Goodglass (1946), Benson • New issue: aphasia and intellectual status, apparently aphasia interferes with other cognitive functioning. • In the 1960's LURIA, but also many other psychologists who had been working in the field (Hunt, Simmel, Benton, and so on.) Neuropsychology Introduction
Karl Lashley cut the cortex every which way to disrupt memory connections: and failed Neuropsychology Introduction
Lashley, K. S. (1963). Brain Mechanism and Intelligence: A quantitative study of injuries to the brain. New York: Dover. • “The whole implication of the data is that the “higher level” integrations are not dependent upon localized structural differentiations but are a function of some more general, dynamic organization of the entire nervous system.” P. 157. • “These phenomena all point to a functional organization independent of differentiated structure and to some more-general energy relations within the central nervous system.” P. 167. • Localization for purposes of targeting areas of damage does not provide an explanation of function. Otherwise this would lead, ultimately, to the localization of single ideas in single neurons. • “The facts which give the chief difficulty to the existing theories may be grouped into four categories: • the determination of reactions by patterns or ratios of excitation imposed upon varying anatomical elements(with this must be included the equipotentiality of cerebral areas and association tracts); • the apparent disturbance of equilibrium among the parts of the central nervous system without specific losses of function, as in the occurrence of more-pronounced symptoms from unilateral lesions to the cerebellum, corpus striatum, etc., than from bilateral lesions; • the dependence of efficiency in learning and retention and, less certainly, of ease of performance upon the quantity of functional tissue; and • the seeming limitation of the possible complexity of organization by the total quantity of nervous tissue. • These phenomena all point to a functional organization independent of differentiated structure and to some more-general energy relations within the central nervous system.” Pp. 166-167 Neuropsychology Introduction
MODERN PERIOD: • Karl Lashley: Mass Action and Equipotentiality • World Wars • Vigotsky, Simmel, Goldstein • Von Monakow's "diathesis" • Teuber, double dissociation • Penfield and Jaspers neurosurgery • Psychometrics and statistical evaluation (Bessel, Galton, Binet) • Brenda Milner: Rasmussen, Wada, Penfield, lateralization after removal of temporal lobes: Doreen Kimura, • Discovery of fluent and non-fluent articulatory aphasia (rather than a normal distribution of fluency) • Goodglass (1946), Benson • New issue: aphasia and intellectual status, apparently aphasia interferes with other cognitive functioning. • In the 1960's LURIA, but also many other psychologists who had been working in the field (Hunt, Simmel, Benton, and so on.) Neuropsychology Introduction
Teuber’s “Double Dissociation” • Teuber, H. L. (1955) Physiological Psychology. Annual Review of Psychology, 6, 267-296. • In this review he introduces the concept of "double dissociation" in which one lesion produces a deficit (skill 1 deficit) with no detriment to a second skill (skill 2 deficit), and a second lesion produces a deficit in the second skill without detriment to the first skill. Neuropsychology Introduction
MODERN PERIOD: • Karl Lashley: Mass Action and Equipotentiality • World Wars • Vigotsky, Simmel, Goldstein • Von Monakow's "diathesis" • Teuber, double dissociation • Penfield and Jaspers neurosurgery • Psychometrics and statistical evaluation (Bessel, Galton, Binet) • Brenda Milner: Rasmussen, Wada, Penfield, lateralization after removal of temporal lobes: Doreen Kimura, • Discovery of fluent and non-fluent articulatory aphasia (rather than a normal distribution of fluency) • Goodglass (1946), Benson • New issue: aphasia and intellectual status, apparently aphasia interferes with other cognitive functioning. • In the 1960's LURIA, but also many other psychologists who had been working in the field (Hunt, Simmel, Benton, and so on.) • Then Halsted (later Reitan), Edit Kaplan (Boston Process Approach) Neuropsychology Introduction
Whitman’s Incomplete List of Reasons Why It Is Difficult to “LOCALIZE FUNCTION” • What is being localized? • What is the role of interactions? • Is the function localized at a macroscopic or microscopic level? • Homologous structures may not have analogous functions. • Higher order properties may emerge from lower level processes. • Recovery of function always contaminates results. • Functions may be redundantly represented in the CNS. • Single nuclei may serve multiple functions. • Only deficits are revealed by lesion studies. • Human data is variable. • Single deficits are rarely seen. • Psychological functions may not be isomorphic with brain function • The nervous system is “plastic.” • Methods of assessment of psychological function may not tap homogenous functions. • Methods of brain assessment (e.g. brain imaging) differ in the type of information obtained. • Methods of brain assessment are time-limited. Neuropsychology Introduction
Techniques • Experimental Design • Correlation • Psychometric comparisons • Double-Dissociation • Neuroimaging: • Evoked • PET • NMR • CITE THE MARTINEZ AND OTHER STUDIES FOR NSF GRANT _- EVOKED POTENTIALS AND THE LATERALIZED PRIMING COURSE OF EVENTS • Martinez, A., et al., Involvement of striate and extrastriate visual cortical areas in spatial attention. Nature Neuroscience, 1999. 4: p. 364-369. • Brefcznski, D.E. and E.A. DeYoe, Nature Neuroscience. 2, A physiological correlate of the 'spotlight' of visual attention(370-374). Neuropsychology Introduction