Anatomy of the Cerebellum Computational Models of Neural
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Functional Imaging of the Deep Cerebellar Nuclei: a Review
Cerebellum (2010) 9:22–28 DOI 10.1007/s12311-009-0119-3 Functional Imaging of the Deep Cerebellar Nuclei: A Review Christophe Habas Published online: 10 June 2009 # Springer Science + Business Media, LLC 2009 Abstract The present mini-review focused on functional and climbing fibers derived from the bulbar olivary nuclei. imaging of human deep cerebellar nuclei, mainly the The mossy-fiber influence on DCN firing appears to be dentate nucleus. Although these nuclei represent the unique weaker than the climbing-fiber influence. Despite the output channel of the cerebellum, few data are available pivotal role of these nuclei, only very few results are concerning their functional role. However, the dentate available for functional imaging of the DCN, including nucleus has been shown to participate in a widespread PET scan and MRI techniques, and most of these data functional network including sensorimotor and associative concern the DN. This lack of data is due to a number of cortices, striatum, hypothalamus, and thalamus, and plays a reasons. minor role in motor execution and a major role in First, the human DCN mainly comprise the large, sensorimotor coordination and learning, and cognition. widespread, and easily identifiable DN which has a marked The dentate nucleus appears to be predominantly involved low-intensity signal on MRI T2*-weighted sequences and in conjunction with the neocerebellum in executive and is clearly distinguished from the adjacent cortical structures. affective networks devoted, at least, to attention, working In contrast, FN and GEN are very thin and are both located memory, procedural reasoning, and salience detection. very close to the gray matter of lobules VIII and IX, while these nuclei are situated on the medial aspect of the DN. -
The Cerebellum in Sagittal Plane-Anatomic-MR Correlation: 2
667 The Cerebellum in Sagittal Plane-Anatomic-MR Correlation: 2. The Cerebellar Hemispheres Gary A. Press 1 Thin (5-mm) sagittal high-field (1 .5-T) MR images of the cerebellar hemispheres James Murakami2 display (1) the superior, middle, and inferior cerebellar peduncles; (2) the primary white Eric Courchesne2 matter branches to the hemispheric lobules including the central, anterior, and posterior Dean P. Berthoty1 quadrangular, superior and inferior semilunar, gracile, biventer, tonsil, and flocculus; Marjorie Grafe3 and (3) several finer secondary white-matter branches to individual folia within the lobules. Surface features of the hemispheres including the deeper fissures (e.g., hori Clayton A. Wiley3 1 zontal, posterolateral, inferior posterior, and inferior anterior) and shallower sulci are John R. Hesselink best delineated on T1-weighted (short TRfshort TE) and T2-weighted (long TR/Iong TE) sequences, which provide greatest contrast between CSF and parenchyma. Correlation of MR studies of three brain specimens and 11 normal volunteers with microtome sections of the anatomic specimens provides criteria for identifying confidently these structures on routine clinical MR. MR should be useful in identifying, localizing, and quantifying cerebellar disease in patients with clinical deficits. The major anatomic structures of the cerebellar vermis are described in a companion article [1). This communication discusses the topographic relationships of the cerebellar hemispheres as seen in the sagittal plane and correlates microtome sections with MR images. Materials, Subjects, and Methods The preparation of the anatomic specimens, MR equipment, specimen and normal volunteer scanning protocols, methods of identifying specific anatomic structures, and system of This article appears in the JulyI August 1989 issue of AJNR and the October 1989 issue of anatomic nomenclature are described in our companion article [1]. -
Basal Ganglia & Cerebellum
1/2/2019 This power point is made available as an educational resource or study aid for your use only. This presentation may not be duplicated for others and should not be redistributed or posted anywhere on the internet or on any personal websites. Your use of this resource is with the acknowledgment and acceptance of those restrictions. Basal Ganglia & Cerebellum – a quick overview MHD-Neuroanatomy – Neuroscience Block Gregory Gruener, MD, MBA, MHPE Vice Dean for Education, SSOM Professor, Department of Neurology LUHS a member of Trinity Health Outcomes you want to accomplish Basal ganglia review Define and identify the major divisions of the basal ganglia List the major basal ganglia functional loops and roles List the components of the basal ganglia functional “circuitry” and associated neurotransmitters Describe the direct and indirect motor pathways and relevance/role of the substantia nigra compacta 1 1/2/2019 Basal Ganglia Terminology Striatum Caudate nucleus Nucleus accumbens Putamen Globus pallidus (pallidum) internal segment (GPi) external segment (GPe) Subthalamic nucleus Substantia nigra compact part (SNc) reticular part (SNr) Basal ganglia “circuitry” • BG have no major outputs to LMNs – Influence LMNs via the cerebral cortex • Input to striatum from cortex is excitatory – Glutamate is the neurotransmitter • Principal output from BG is via GPi + SNr – Output to thalamus, GABA is the neurotransmitter • Thalamocortical projections are excitatory – Concerned with motor “intention” • Balance of excitatory & inhibitory inputs to striatum, determine whether thalamus is suppressed BG circuits are parallel loops • Motor loop – Concerned with learned movements • Cognitive loop – Concerned with motor “intention” • Limbic loop – Emotional aspects of movements • Oculomotor loop – Concerned with voluntary saccades (fast eye-movements) 2 1/2/2019 Basal ganglia “circuitry” Cortex Striatum Thalamus GPi + SNr Nolte. -
Introduction
Cambridge University Press 978-1-316-64693-9 — The Brain and Behavior 4th Edition Excerpt More Information Chapter1 Introduction Introduction Theneuraxisinthehumanrunsasanimaginary straight line through the center of the spinal cord Human behavior is a direct reflection of the anatomy and brainstem (Figure 1.1). At the level of the junc- and physiology of the central nervous system. The goal tion of the midbrain and diencephalon, however, the of the behavioral neuroscientist is to uncover the neu- neuraxis changes orientation and extends from the roanatomical substrates of behavior. Complex mental occipital pole to the frontal pole (Figure 1.1). processes are represented in the brain by their elemen- The neuraxis located above the midbrain is the neur- tary components. Elaborate mental functions consist of axis of the cerebrum and is sometimes called the subfunctions and are constructed from both serial and horizontal neuraxis. A cross-section taken perpendi- parallel interconnections of several brain regions. cular to the horizontal neuraxis is called a coronal An introduction to the nervous system covers general (frontal) section. terminology and the ventricular system. With regard to the neuraxis of the spinal cord and brainstem: Major Subdivisions • Dorsal (posterior) means toward the back. The nervous system is divided anatomically into the • Ventral (anterior) means toward the abdomen. central nervous system (CNS) and the peripheral ner- • Rostral means toward the nose. vous system (PNS). • Caudal means toward the tail. • The CNS is made up of the brain and spinal cord. • The sagittal (midsagittal) plane is the vertical • The PNS consists of the cranial nerves and spinal plane that passes through the neuraxis. -
Intrinsic Neurons of Fastigial Nucleus Mediate Neurogenic Neuroprotection Against Excitotoxic and Ischemic Neuronal Injury in Rat
The Journal of Neuroscience, May 15, 1999, 19(10):4142–4154 Intrinsic Neurons of Fastigial Nucleus Mediate Neurogenic Neuroprotection against Excitotoxic and Ischemic Neuronal Injury in Rat Sara B. Glickstein, Eugene V. Golanov, and Donald J. Reis Department of Neurology and Neuroscience, Cornell University Medical College, New York, New York 10021 Electrical stimulation of the cerebellar fastigial nucleus (FN) of FN, but not DN, abolished neuroprotection but not the elevates regional cerebral blood flow (rCBF) and arterial pres- elevations of rCBF and AP elicited from FN stimulation. Exci- sure (AP) and provides long-lasting protection against focal and totoxic lesions of FN, but not DN, also abolished the 37% global ischemic infarctions. We investigated which neuronal reduction in focal ischemic infarctions produced by middle element in FN, perikarya or axons, mediates this central neu- cerebral artery occlusion. Excitation of intrinsic FN neurons rogenic neuroprotection and whether it also protects against provides long-lasting, substantial, and reversible protection of excitotoxicity. In anesthetized rats, the FN was stimulated for 1 central neurons from excitotoxicity, as well as focal ischemia, hr, and ibotenic acid (IBO) was microinjected unilaterally into whereas axons in the nucleus, probably collaterals of ramified the striatum. In unstimulated controls, the excitotoxic lesions brainstem neurons, mediate the elevations in rCBF, which do averaged ;40 mm 3. Stimulation of FN, but not dentate nucleus not contribute to neuroprotection. Long-lived protection (DN), significantly reduced lesion volumes up to 80% when IBO against a range of injuries is an unrecognized function of FN was injected 15 min, 72 hr, or 10 d, but not 30 d, thereafter. -
Anatomy of Cerebellum Rajasekhar Sajja Srinivasa Siva Naga
Chapter Anatomy of Cerebellum Rajasekhar Sajja Srinivasa Siva Naga Abstract The cerebellum receives inputs from spinal cord, cerebrum, brainstem, and sensory systems of the body and controls the motor system of the body. The Cerebellum harmonizes the voluntary motor activities such as maintenance of posture and equilibrium, and coordination of voluntary muscular activity including learning of the motor behaviours. Cerebellum occupies posterior cranial fossa, and it is relatively a small part of the brain. It weighs about one tenth of the total brain. Cerebellar lesions do not cause motor or cognitive impairment. However, they cause slowing of movements, tremors, lack of equilibrium/balance. Complex motor action becomes shaky and faltering. Keywords: Cerebellum, Spinocerebellar ataxia, Cortex, Medulla, Peduncles, Nuclei 1. Introduction The Cerebellum is the largest part of the hindbrain and develops from the alar plates (rhombic lips) of the metencephalon. It lies between the temporal and occipital lobes of cerebrum and the brainstem in the posterior cranial fossa. It is attached to the posterior surface of the brainstem by three large white fibre bundles. It is attached to the midbrain by superior cerebel- lar peduncle, pons by middle cerebellar peduncle, and medulla by inferior cerebellar peduncle. Cerebellum is concerned with three primary functions: a) coordination of voluntary motor functions of the body initiated by the cerebral cortex at an uncon- scious level, b) maintenance of balance, and posture, c) Maintenance of muscle tone. It receives and integrates the sensory inputs from the cerebrum and the spinal cord necessary for a planning and smooth coordination of the movements [1]. Cerebellar lesions result in irregular and uncoordinated, awkward intentional muscle movements. -
Muscimol Microinjection Into Cerebellar Fastigial Nucleus Exacerbates Stress-Induced Gastric Mucosal Damage in Rats
Acta Pharmacologica Sinica (2013) 34: 205–213 npg © 2013 CPS and SIMM All rights reserved 1671-4083/13 $32.00 www.nature.com/aps Original Article Muscimol microinjection into cerebellar fastigial nucleus exacerbates stress-induced gastric mucosal damage in rats Jin-zhou ZHU1, 2, #, Su-juan FEI1, #, Jian-fu ZHANG1, 2, *, Sheng-ping ZHU1, 2, Zhang-bo LIU1, 2, Ting-ting LI1, 2, Xiao QIAO1, 2 1Department of Gastroenterology, Affiliated Hospital of Xuzhou Medical College, Xuzhou 221002, China; 2Department of Physiology, Xuzhou Medical College, Xuzhou 221002, China Aim: To investigate the effects of microinjection of the GABAA receptor agonist muscimol into cerebellar fastigial nucleus (FN) on stress- induced gastric mucosal damage and the underlying mechanism in rats. Methods: Stress-induced gastric mucosal damage was induced in adult male SD rats by restraining and immersing them in cold water for 3 h. GABAA receptor agonist or antagonist was microinjected into the lateral FN. The decussation of superior cerebellar peduncle (DSCP) was electrically destroyed and the lateral hypothalamic area (LHA) was chemically ablated by microinjection of kainic acid. The pathological changes in the gastric mucosa were evaluated using TUNEL staining, immunohistochemistry staining and Western blotting. Results: Microinjection of muscimol (1.25, 2.5, and 5.0 µg) into FN significantly exacerbated the stress-induced gastric mucosal damage in a dose-dependent manner, whereas microinjection of GABAA receptor antagonist bicuculline attenuated the damage. The intensifying effect of muscimol on gastric mucosal damage was abolished by electrical lesion of DSCP or chemical ablation of LHA performed 3 d before microinjection of muscimol. Microinjection of muscimol markedly increased the discharge frequency of the greater splanchnic nerve, significantly increased the gastric acid volume and acidity, and further reduced the gastric mucosal blood flow. -
Nucleus Dorsalis Superficialis (Lateralis Dorsalis) of the Thalamus and the Limbic System in Man
J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.37.7.765 on 1 July 1974. Downloaded from Joutrnal of Neur)ology, Neurosurgery, and Psychiatry, 1974, 37, 765-789 Nucleus dorsalis superficialis (lateralis dorsalis) of the thalamus and the limbic system in man J. M. VAN BUREN AND R. C. BORKE Fr-om the Surgical Neurology Branch, National Institute of Neurological Diseases and Str-oke, National Institutes of Health, Bethesda, Maryland, U.S.A. SYNOPSIS Although the earlier supposition was that the n. dorsalis superficialis (n. lateralis dorsalis) of the thalamus projected to the parietal region, more recent evidence has linked it to the posterior cingulate gyrus and possibly adjacent regions near the splenium of the corpus callosum. An afferent supply from lower levels was in more doubt, although some report had been made of cell and fibre degeneration in the n. dorsalis superficialis after extensive temporal resections and section of the fornix in lower primates. The five human hemispheres of the present study all had lesions of long duration below the level of the splenium of the corpus callosum in the posteromedial temporal region. All showed marked degeneration in the fornix and n. dorsalis superficialis. In favourably Protected by copyright. stained cases, gliotic fascicles could be followed from the descending column of the fornix to the n. dorsalis superficialis via the region lateral to the stria medullaris thalami. The cell loss in the nucleus thus appeared to be an instance of anterograde transynaptic degeneration. These cases provided an interesting instance in which human infarctions provided natural lesions that would have been hard to duplicate in experimental animals. -
Anatomy of Cerebellum and Relevant Connections
Anatomy of Cerebellum and Relevant Connections Lecture (14) . Important . Doctors Notes Please check our Editing File . Notes/Extra explanation هذا العمل مبني بشكل أساسي على عمل دفعة 436 مع المراجعة {ومنْْيتو َ ّكْْع َلْْا ِّْللْفَهُوْْحس بهْ} َ َ َ َ َ َ َ َ َ ُ ُ والتدقيق وإضافة المﻻحظات وﻻ يغني عن المصدر اﻷساسي للمذاكرة . Objectives At the end of the lecture, students should be able to: Describe the External features of the cerebellum (lobes, fissures). Describe briefly the Internal structure of the cerebellum. List the name of Cerebellar Nuclei. Relate the Anatomical to the Functional Subdivisions of the cerebellum. Describe the Important connections of each subdivision. Describe briefly the Main Effects in case of lesion of the cerebellum. Cerebellum o Origin: from Hindbrain. Playlist o Position: lies behind Pons & Medulla Separated from them by Fourth ventricle. o Connection: to the brainstem by Inferior, Middle & Superior Cerebellar Peduncles. (medulla) (pons) (midbrain) Extra Cerebellum has 3 fissures: - 2 main (primary) fissures (related to lobes): primary and secondary Cerebellum (posterolateral) - Horizontal fissure (largest/deepest) External Features and not related to lobes o Superior It consists of two Cerebellar Hemispheres joined vermis in midline by the Vermis. and paravermis (intermediate zone) is between vermis and hemisphere inferior o Its surface is highly convoluted forming Folia vermis (like gyri), separated by Fissures (like sulci). Anatomical Subdivision 1. Anterior lobe: in front of primary fissure, on the superior surface. 2. Posterior (middle) lobe: behind primary fissure (Between Primary & Secondary/posterolateral fissures). 3. Flocculonodular lobe: in front of secondary (Posterolateral) fissure, on the inferior surface . -
Neuroimaging Evidence Implicating Cerebellum in the Experience of Hypercapnia and Hunger for Air
Neuroimaging evidence implicating cerebellum in the experience of hypercapnia and hunger for air Lawrence M. Parsons*†, Gary Egan‡, Mario Liotti*, Stephen Brannan*, Derek Denton‡, Robert Shade§, Rachael Robillard¶, Lisa Madden§, Bart Abplanalp¶, and Peter T. Fox* *Research Imaging Center, University of Texas Health Science Center, San Antonio, TX 78284; ‡Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Victoria 3052, Australia; §Southwest Foundation for Biomedical Research, P. O. Box 760549, San Antonio, TX 78245-0549; and ¶Departments of Psychology and Educational Psychology, University of Texas, Austin, TX 78712 Contributed by Derek Denton, December 20, 2000 Recent neuroimaging and neurological data implicate cerebellum areas (20–23). Anatomical tracer labeling data in rat (24) in nonmotor sensory, cognitive, vegetative, and affective func- indicate that a number of cerebellar areas send and͞or receive tions. The present study assessed cerebellar responses when the projections from the VRG, which contains the structures nec- urge to breathe is stimulated by inhaled CO2. Ventilation changes essary for respiratory rhythm generation (25–30). The cerebellar follow arterial blood partial pressure CO2 changes sensed by the areas connected to the VRG are quadrangular (VI), central medullary ventral respiratory group (VRG) and hypothalamus, (III), lingula (I, II), and inferior semilunar (Crus II) lobules, as entraining changes in midbrain, pons, thalamus, limbic, paralimbic, well as fastigial nucleus, interposed nucleus, and dentate nuclei, and insular regions. Nearly all these areas are known to connect the output nuclei for the vermal, intermediate, and lateral anatomically with the cerebellum. Using positron emission tomog- regions of cerebellum. Moreover, cerebellum has known con- raphy, we measured regional brain blood flow during acute CO2- nectivity to the hypothalamus, thalamus, pons, and midbrain induced breathlessness in humans. -
Cerebellar Histology & Circuitry
Cerebellar Histology & Circuitry Histology > Neurological System > Neurological System CEREBELLAR HISTOLOGY & CIRCUITRY SUMMARY OVERVIEW Gross Anatomy • The folding of the cerebellum into lobes, lobules, and folia allows it to assume a tightly packed, inconspicuous appearance in the posterior fossa. • The cerebellum has a vast surface area, however, and when stretched, it has a rostrocaudal expanse of roughly 120 centimeters, which allows it to hold an estimated one hundred billion granule cells — more cells than exist within the entire cerebral cortex. - It is presumed that the cerebellum's extraordinary cell count plays an important role in the remarkable rehabilitation commonly observed in cerebellar stroke. Histology Two main classes of cerebellar nuclei • Cerebellar cortical neurons • Deep cerebellar nuclei CEREBELLAR CORTICAL CELL LAYERS Internal to external: Subcortical white matter Granule layer (highly cellular) • Contains granule cells, Golgi cells, and unipolar brush cells. Purkinje layer 1 / 9 • Single layer of large Purkinje cell bodies. • Purkinje cells project a fine axon through the granule cell layer. - Purkinje cells possess a large dendritic system that arborizes (branches) extensively and a single fine axon. Molecular layer • Primarily comprises cell processes but also contains stellate and basket cells. DEEP CEREBELLAR NUCLEI From medial to lateral: Fastigial Globose Emboliform Dentate The globose and emboliform nuclei are also known as the interposed nuclei • A classic acronym for the lateral to medial organization of the deep nuclei is "Don't Eat Greasy Food," for dentate, emboliform, globose, and fastigial. NEURONS/FUNCTIONAL MODULES • Fastigial nucleus plays a role in the vestibulo- and spinocerebellum. • Interposed nuclei are part of the spinocerebellum. • Dentate nucleus is part of the pontocerebellum. -
The Cerebellum: 3
41 The Cerebellum: 3. Anatomic-MR Correlation in the Coronal Plane Gary A. Press 1 Thin (5-mm) coronal high-field (1.5-T) MR images of four human brain specimens and James W. Murakami2 14 normal volunteers were correlated with myelin-stained microtomic sections of the Eric Courchesne2 specimen cerebella. The primary white-matter tracts innervating several hemispheric Marjorie Grafe3 (posterior quadrangular, superior, and inferior semilunar, gracile, biventer, tonsil) and John R. Hesselink1 vermian (declive, folium, tuber) lobules are oriented perpendicularly to the coronal plane of section and are shown well on proton-density-weighted (long TR/short TE) and T2- weighted (long TR/Iong TE) spin-echo images, which provide excellent contrast between gray and white matter. Several of the surface sulci and fissures of the cerebellar hemispheres (including the superior posterior, horizontal, secondary, and posterolateral fissures) also course perpendicular to the coronal plane and are depicted well on T1- weighted (short TR/short TE) and T2-weighted images, which maximize contrast be tween CSF and parenchyma. The opportunity for side-to-side comparison of the hemi spheres is a distinct advantage of the coronal view. Nevertheless, more obliquely oriented surfaces (preculminate, primary, inferior posterior, inferior anterior, and intra biventral fissures) and deep hemispheric structures (primary white-matter tracts to central, anterior quadrangular, and floccular lobules) may be obscured by volume averaging in the coronal plane; moreover, much of the finer anatomy of the vermis is depicted poorly. The constant surface and deep anatomy of the cerebellum revealed on coronal images in normal volunteers encourages detailed mapping. MR imaging in the coronal plane should be especially useful in identifying, localizing, and quantifying normal and abnormal morphologic differences between the cerebellar hemispheres.