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Chapter 12 Central Nervous System

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CHAPTER 12 CENTRAL NERVOUS SYSTEM Copyright © 2010 Pearson Education, Inc. CENTRAL NERVOUS SYSTEM Embryonic Development Copyright © 2010 Pearson Education, Inc. Figure 12.1 Development of the neural tube from embryonic ectoderm (1 of 4). Surface Head ectoderm Neural plate Tail 1 The neural plate forms from surface ectoderm. Copyright © 2010 Pearson Education, Inc. Figure 12.1 Development of the neural tube from embryonic ectoderm (2 of 4). Neural folds Neural groove 2 The neural plate invaginates, forming the neural groove, flanked by neural folds. Copyright © 2010 Pearson Education, Inc. Figure 12.1 Development of the neural tube from embryonic ectoderm (3 of 4). Neural crest 3 Neural fold cells migrate to form the neural crest, which will form much of the PNS and many other structures. Copyright © 2010 Pearson Education, Inc. Figure 12.1 Development of the neural tube from embryonic ectoderm (4 of 4). Head Surface ectoderm Neural tube Tail 4 The neural groove becomes the neural tube, which will form CNS structures. Copyright © 2010 Pearson Education, Inc. Neural tube formation involves all of these stages except… 1) Neural plate 2) Neural ring 3) Neural groove 4) Surface ectoderm 5) Neural tube Copyright © 2010 Pearson Education, Inc. Figure 12.2 Embryonic development of the human brain. (a) (b) Primary brain (c) Secondary brain (d) Adult brain (e) Adult Neural vesicles vesicles structures neural tube canal regions Cerebrum: cerebral Lateral hemispheres (cortex, Telencephalon ventricles white matter, basal nuclei) Anterior Prosencephalon Diencephalon (rostral) (forebrain) Diencephalon (thalamus, hypothalamus, Third ventricle epithalamus), retina Mesencephalon Cerebral Mesencephalon Brain stem: midbrain (midbrain) aqueduct Rhombencephalon Metencephalon Brain stem: pons (hindbrain) Cerebellum Fourth ventricle Myelencephalon Brain stem: medulla Posterior oblongata (caudal) Spinal cord Central canal Copyright © 2010 Pearson Education, Inc. Which of these adult brain structures is derived from the prosencephalon? 1) Brain stem 2) Cerebellum 3) Cerebrum 4) All of the above Copyright © 2010 Pearson Education, Inc. CENTRAL NERVOUS SYSTEM Regions and Organization Copyright © 2010 Pearson Education, Inc. Figure 12.3d Effect of space restriction on brain development. Cerebral hemisphere Diencephalon Cerebellum Brain stem • Midbrain • Pons • Medulla (d) Birth oblongata Copyright © 2010 Pearson Education, Inc. Figure 12.4 Pattern of gray and white matter in the CNS (highly simplified). Central cavity Cortex of gray matter Migratory Inner gray pattern of matter neurons Cerebrum Outer white Cerebellum matter Gray matter Region of cerebellum Central cavity Inner gray matter Outer white matter Gray matter Brain stem Central cavity Outer white matter Inner gray matter Spinal cord Copyright © 2010 Pearson Education, Inc. CENTRAL NERVOUS SYSTEM Ventricles Copyright © 2010 Pearson Education, Inc. Figure 12.5 Ventricles of the brain. Lateral ventricle Septum pellucidum Anterior horn Posterior horn Inferior horn Interventricular Lateral foramen aperture Third ventricle Median aperture Inferior horn Lateral Cerebral aqueduct aperture Fourth ventricle Central canal (a) Anterior view (b) Left lateral view Copyright © 2010 Pearson Education, Inc. White matter represents… 1) High density areas of neuron cell bodies 2) Muscle 3) Blood vessels 4) High density areas of unmyelinated axons 5) High density areas of myelinated axons Copyright © 2010 Pearson Education, Inc. True or false: The central canal of the spinal Cord is continuous with the ventricles of the Brain. 1) True 2) False Copyright © 2010 Pearson Education, Inc. CENTRAL NERVOUS SYSTEM Cerebral Hemispheres: Cerebral Cortex Copyright © 2010 Pearson Education, Inc. Figure 12.6a Lobes and fissures of the cerebral hemispheres. Precentral Central gyrus sulcus Postcentral Frontal gyrus lobe Parietal lobe Parieto-occipital sulcus (on medial surface of hemisphere) Lateral sulcus Occipital lobe Temporal lobe Transverse cerebral fissure Cerebellum Pons Fissure Medulla oblongata (a deep Spinal cord sulcus) Gyrus Cortex (gray matter) Sulcus White matter (a) Copyright © 2010 Pearson Education, Inc. Figure 12.6b Lobes and fissures of the cerebral hemispheres. Central Frontal lobe sulcus Gyri of insula Temporal lobe (pulled down) (b) Copyright © 2010 Pearson Education, Inc. Figure 12.6c Lobes and fissures of the cerebral hemispheres. Anterior Longitudinal Frontal lobe fissure Cerebral veins and arteries Parietal covered by lobe arachnoid mater Left cerebral Right cerebral hemisphere hemisphere Occipital lobe (c) Posterior Copyright © 2010 Pearson Education, Inc. Figure 12.7 Functional neuroimaging (fMRI) of the cerebral cortex. Central sulcus Longitudinal Left frontal Left temporal Areas active fissure lobe lobe in speech and hearing (fMRI) Copyright © 2010 Pearson Education, Inc. Figure 12.8a Functional and structural areas of the cerebral cortex. Motor areas Central sulcus Sensory areas and related Primary motor cortex association areas Premotor cortex Primary somatosensory cortex Frontal eye field Somatic Somatosensory sensation association cortex Broca’s area Gustatory cortex (outlined by dashes) Taste (in insula) Prefrontal cortex Working memory Wernicke’s area for spatial tasks (outlined by dashes) Executive area for task management Working memory for Primary visual object-recall tasks cortex Vision Solving complex, Visual multitask problems association area Auditory association area Hearing Primary auditory cortex (a) Lateral view, left cerebral hemisphere Primary motor cortex Motor association cortex Primary sensory cortex Sensory association cortex Multimodal association cortex Copyright © 2010 Pearson Education, Inc. Figure 12.8b Functional and structural areas of the cerebral cortex. Cingulate Primary Premotor cortex gyrus motor cortex Central sulcus Corpus Primary somatosensory callosum cortex Frontal eye field Parietal lobe Prefrontal Somatosensory cortex association cortex Parieto-occipital sulcus Processes emotions Occipital related to personal lobe and social interactions Visual Orbitofrontal association area cortex Olfactory bulb Olfactory tract Primary Fornix visual cortex Temporal lobe Uncus Calcarine sulcus Primary Parahippocampal olfactory cortex gyrus (b) Parasagittal view, right hemisphere Primary motor cortex Motor association cortex Primary sensory cortex Sensory association cortex Multimodal association cortex Copyright © 2010 Pearson Education, Inc. Figure 12.9 Body maps in the primary motor cortex and somatosensory cortex of the cerebrum. Posterior Motor Sensory Motor map in Anterior Sensory map in precentral gyrus postcentral gyrus Toes Genitals Jaw Tongue Primary motor Primary somato- cortex sensory cortex Intra- Swallowing (precentral gyrus) (postcentral gyrus) abdominal Copyright © 2010 Pearson Education, Inc. Quiz Q1: All of these are true of the primary motor cortex except it… 1) Is located anterior to the central sulcus 2) Is located on the precentral gyrus 3) Controls voluntary muscle movement 4) Coordinates repeated/learned complex muscle movements Copyright © 2010 Pearson Education, Inc. Quiz Q2: The sensory homunculus has the fingers mapped to a large area of the brain because… 1) The fingers have a very large surface area 2) The fingers have lots of muscles required to move them 3) The fingers contain many sensory receptors 4) All of the above Copyright © 2010 Pearson Education, Inc. Quiz Q3: True or false: The neural crest develops into the central nervous system. 1) True 2) False Copyright © 2010 Pearson Education, Inc. Quiz Q4: Information from the premotor cortex mostly gets sent to… 1) muscles directly. 2) the primary somatosensory cortex 3) the somatosensory association cortex 4) the primary motor cortex Copyright © 2010 Pearson Education, Inc. Quiz Q5: Gray matter includes… 1) myelinated axons 2) neuron cell bodies 3) Schwann cells 4) ganglia Copyright © 2010 Pearson Education, Inc. Figure 12.10 Types of fiber tracts in white matter. Longitudinal fissure Association fibers Superior Lateral Commissural fibers (corpus callosum) ventricle Corona Basal nuclei radiata • Caudate • Putamen • Globus Fornix pallidus Internal Thalamus capsule Gray matter Third White matter ventricle Projection Pons fibers Decussation Medulla oblongata of pyramids (a) (b) Copyright © 2010 Pearson Education, Inc. Figure 12.11a Basal nuclei. Fibers of corona radiata Caudate nucleus Thalamus Lentiform Tail of Corpus nucleus caudate striatum • Putamen • Globus pallidus nucleus (deep to putamen) Projection fibers run deep to (a) lentiform nucleus Copyright © 2010 Pearson Education, Inc. Figure 12.11b Basal nuclei (1 of 2). Anterior Cerebral cortex Cerebral white matter Corpus callosum Anterior horn of lateral ventricle Caudate nucleus Putamen Globus Lentiform pallidus nucleus Thalamus Tail of caudate nucleus Third ventricle Inferior horn of lateral ventricle (b) Posterior Copyright © 2010 Pearson Education, Inc. Figure 12.11b Basal nuclei (2 of 2). Cerebral cortex Cerebral white matter Corpus callosum Anterior horn of lateral ventricle Caudate nucleus Lentiform nucleus Thalamus Third ventricle Inferior horn of lateral ventricle (b) Copyright © 2010 Pearson Education, Inc. Basal nuclei are… 1) Part of the cerebral cortex 2) Part of the cerebral hemispheres 3) Gray matter 4) 2 and 3 only 5) All of the above Copyright © 2010 Pearson Education, Inc. CENTRAL NERVOUS SYSTEM Cerebral Hemispheres: Lateralization and Contralateralization Copyright © 2010 Pearson Education, Inc. CENTRAL NERVOUS
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