Cerebral hemisphere - wikipedia Cerebral hemisphere Cerebral hemisphere Human brain seen from front. The sheep brain seen from the back. Opening longitudinal fissure, the fissure which separates left and right cerebral hemispheres. Details Identifiers Latin Hemisphaerium cerebri NeuroLex ID Hemisphere of cerebral cortex TA A14. 1.09. 002 FMA 61817 Anatomical terms of neuroanatomy ( edit on Wikidata ) The vertebrate cerebrum ( brain ) is formed by two cerebral hemispheres that are separated by a groove, the longitudinal fissure. The brain can thus be described as being divided into left and right cerebral hemispheres. Each of these hemispheres has an outer layer of grey matter, the cerebral cortex, that is supported by an inner layer of white matter. In eutherian ( placental ) mammals, the hemispheres are linked by the corpus callosum, a very large bundle of nerve fibers. Smaller commissures, including the anterior commissure, the posterior commissure and the fornix, also join the hemispheres and these are also present in other vertebrates. These commissures transfer information between the two hemispheres to coordinate localized functions. There are three known poles of the cerebral hemispheres named : the occipital pole, the frontal pole, and the temporal lobe. The central sulcus is a prominent fissure which separates the parietal lobe from the frontal lobe and the primary motor cortex from the primary somatosensory cortex. Macroscopically the hemispheres are roughly mirror images of each other, with only subtle differences, such as the Yakovlevian torque seen in the human brain, which is a slight warping of the right side, bringing it just forward of the left side. On a microscopic level, the cytoarchitecture of the cerebral cortex, shows the functions of cells, quantities of neurotransmitter levels and receptor subtypes to be markedly asymmetrical between the hemispheres. However, while some of these hemispheric distribution differences are consistent across human beings, or even across some species, many observable distribution differences vary from individual to individual within a given species. Contents 1 Structure 2 Composition 2.1 Development 3 Function 3.1 Hemisphere lateralization 4 Clinical significance 5 Additional images 6 References Structure Each cerebral hemisphere has an outer layer of cerebral cortex which is of grey matter and in the interior of the cerebral hemispheres is an inner layer or core of white matter known as the centrum semiovale. The interior portion of the hemispheres of the cerebrum includes the lateral ventricles, the basal nuclei, and the white matter. Composition If the upper part of either hemisphere be removed, at a level about 1.25 cm. above the corpus callosum, the central white matter will be exposed as an oval - shaped area, the centrum ovale minus, surrounded by a narrow convoluted margin of gray substance, and studded with numerous minute red dots ( puncta vasculosa ), produced by the escape of blood from divided bloodvessels. If the remaining portions of the hemispheres be slightly drawn apart a broad band of white substance, the corpus callosum, will be observed, connecting them at the bottom of the longitudinal fissure ; the margins of the hemispheres which overlap the corpus callosum are called the labia cerebri. Each labium is part of the cingulate gyrus already described ; and the slit - like interval between it and the upper surface of the corpus callosum is termed the callosal sulcus. If the hemispheres be sliced off to a level with the upper surface of the corpus callosum, the white substance of that structure will be seen connecting the two hemispheres. The large expanse of medullary matter now exposed, surrounded by the convoluted margin of gray substance, is called the centrum ovale majus. The blood supply to the centrum ovale is from the superficial middle cerebral artery. The cortical branches of this artery descend to provide blood to the centrum ovale. Development The cerebral hemispheres are derived from the telencephalon. They arise five weeks after conception as bilateral invaginations of the walls. The hemispheres grow round in a C - shape and then back again, pulling all structures internal to the hemispheres ( such as the ventricles ) with them. The intraventricular foramina ( also called the foramina of Monro ) allows communication with the lateral ventricles. The choroid plexus is formed from ependymal cells and vascular mesenchyme. Function Hemisphere lateralization Main article : Lateralization of brain function Broad generalizations are often made in popular psychology about certain functions ( e.g. logic, creativity ) being lateralized, that is, located in the right or left side of the brain. These claims are often inaccurate, as most brain functions are actually distributed across both hemispheres. Most scientific evidence for asymmetry relates to low - level perceptual functions rather than the higher - level functions popularly discussed ( e.g. subconscious processing of grammar, not `` logical thinking '' in general ). The best example of an established lateralization is that of Broca 's and Wernicke 's Areas ( language ) where both are often found exclusively on the left hemisphere. These areas frequently correspond to handedness however, meaning the localization of these areas is regularly found on the hemisphere opposite to the dominant hand. Function lateralization such as semantics, prosodic, intonation, accentuation, prosody, etc. has since been called into question and largely been found to have a neuronal basis in both hemispheres. Cerebral hemispheres of a human embryo at 8 weeks. Perceptual information is processed in both hemispheres, but is laterally partitioned : information from each side of the body is sent to the opposite hemisphere ( visual information is partitioned somewhat differently, but still lateralized ). Similarly, motor control signals sent out to the body also come from the hemisphere on the opposite side. Thus, hand preference ( which hand someone prefers to use ) is also related to hemisphere lateralization. In some aspects, the hemispheres are asymmetrical ; one side is slightly bigger. There are higher levels of the neurotransmitter norepinephrine on the right and higher levels of dopamine on the left. There is more white matter ( longer axons ) on right and more grey matter ( cell bodies ) on the left. Linear reasoning functions of language such as grammar and word production are often lateralized to the left hemisphere of the brain. In contrast, holistic reasoning functions of language such as intonation and emphasis are often lateralized to the right hemisphere of the brain. Other integrative functions such as intuitive or heuristic arithmetic, binaural sound localization, etc. seem to be more bilaterally controlled. Clinical significance Infarcts of the centrum ovale can occur. As a treatment for epilepsy the corpus callosum may be severed to cut the major connection between the hemispheres in a procedure known as a corpus callosotomy. A hemispherectomy is the removal or disabling of one of the hemispheres of the brain. This is a rare procedure used in some extreme cases of seizures which are unresponsive to other treatments. Additional images Lateral surface. ( Frontal pole is approximately at 10, occipital pole is approximately at 17, and temporal pole is approximately at 38. ) Poles of cerebral hemispheres References Jump up ^ Anderson, B. ; Rutledge, V. ( 1996 ). `` Age and hemisphere effects on dendritic structure ''. Brain. 119 : 1983 -- 1990. doi : 10.1093 / brain / 119.6. 1983. Jump up ^ Hutsler, J. ; Galuske, R.A.W. ( 2003 ). `` Hemispheric asymmetries in cerebral cortical networks ''. Trends in Neurosciences. 26 ( 8 ) : 429 -- 435. doi : 10.1016 / S0166 - 2236 ( 03 ) 00198 - X. ^ Jump up to : Bogousslavsky, J ; Regli, F ( October 1992 ). `` Centrum ovale infarcts : subcortical infarction in the superficial territory of the middle cerebral artery. ''. Neurology. 42 ( 10 ) : 1992 -- 8. PMID 1340771. doi : 10.1212 / wnl. 42.10. 1992. Jump up ^ Snell, Richard S. ( 2009 ). Clinical Neuroanatomy ( Clinical Neuroanatomy for Medical Students ( Snell ) ). Hagerstwon, MD : Lippincott Williams & Wilkins. p. 262. ISBN 0 - 7817 - 9427 - 7. Jump up ^ Lee, PH ( 1 December 2005 ). `` Pathogenesis of deep white matter medullary infarcts : a diffusion weighted magnetic resonance imaging study ''. Journal of Neurology, Neurosurgery & Psychiatry. 76 ( 12 ) : 1659 -- 1663. doi : 10.1136 / jnnp. 2005.066860. Jump up ^ Western et al. 2006 `` Psychology : Australian and New Zealand edition '' John Wiley p. 107 Jump up ^ `` Neuromyth 6 '' http://www.oecd.org/document/63/0,3746,en_2649_35845581_34555007_1_1_1_1,00.html Retrieved October 15, 2011. Jump up ^ Weiss, Peter H., and Simon D. Ubben. `` Where Language Meets Meaningful Action : A Combined Behavior and Lesion. '' Springer. 29 Oct. 2014. Web. 31 Mar. 2016. Jump up ^ Riès, Stephanie K., and Nina F. Dronkers. `` Choosing Words : Left Hemisphere, Right Hemisphere, or Both ? Perspective on the Lateralization of Word Retrieval. '' Wiley Online Library. 14 Jan. 2016. Web. 31 Mar. 2016. Jump up ^ R. Carter, Mapping the Mind, Phoenix, London, 2004, Originally Weidenfeld and Nicolson, 1998. Jump up ^ Dehaene S, Spelke E, Pinel P, Stanescu R, Tsivkin S ( 1999 ). `` Sources of mathematical thinking : behavioral and brain - imaging evidence ''. Science. 284 ( 5416 ) : 970 -- 4. PMID 10320379. doi : 10.1126 / science. 284.5416. 970. Wikimedia Commons has media related to Cerebral hemispheres. Anatomy of the cerebral cortex of the human brain Frontal lobe Superolateral Prefrontal Superior frontal gyrus 6 8 Middle frontal gyrus 9 10 46 Inferior frontal gyrus : 11 47 - Pars orbitalis Broca 's area 44 - Pars opercularis 45 - Pars triangularis Superior frontal sulcus Inferior frontal sulcus Precentral Precentral gyrus Precentral sulcus Medial / inferior Prefrontal Superior frontal gyrus 6 Medial frontal gyrus 8 9 Paraterminal gyrus / Paraolfactory area 12 Straight gyrus 11 Orbital gyri / Orbitofrontal cortex 10 11 12 Ventromedial prefrontal cortex 10 Subcallosal area 25 Olfactory sulcus Orbital sulcus Precentral Paracentral lobule Paracentral sulcus Both Primary motor cortex Premotor cortex 6 Supplementary motor area 6 Supplementary eye field 6 Frontal eye fields 8 Parietal lobe Superolateral Superior parietal lobule 5 7 Inferior parietal lobule 40 - Supramarginal gyrus 39 - Angular gyrus Parietal operculum 43 Intraparietal sulcus Medial / inferior Paracentral lobule 5 Precuneus 7 Marginal sulcus Both Postcentral gyrus / Primary somatosensory cortex Secondary somatosensory cortex 5 Posterior parietal cortex 7 Occipital lobe Superolateral Occipital pole of cerebrum Lateral occipital gyrus 18 19 Lunate sulcus Transverse occipital sulcus Medial / inferior Visual cortex 17 Cuneus Lingual gyrus Calcarine sulcus Temporal lobe Superolateral Transverse temporal gyrus / Auditory cortex 41 42 Superior temporal gyrus 38 22 / Wernicke 's area Middle temporal gyrus 21 Superior temporal sulcus Medial / inferior Fusiform gyrus 37 Medial temporal lobe 27 28 34 35 36 Inferior temporal gyrus 20 Inferior temporal sulcus Interlobar sulci / fissures Superolateral Central ( frontal + parietal ) Lateral ( frontal + parietal + temporal ) Parieto - occipital Preoccipital notch Medial / inferior Longitudinal fissure Cingulate ( frontal + cingulate ) Collateral ( temporal + occipital ) Callosal sulcus Limbic lobe Parahippocampal gyrus anterior Entorhinal cortex Perirhinal cortex Postrhinal cortex Posterior parahippocampal gyrus Prepyriform area Cingulate cortex / gyrus Subgenual area 25 Anterior cingulate 24 32 33 Posterior cingulate 23 31 Isthmus of cingulate gyrus : Retrosplenial cortex 26 29 30 Hippocampal formation Hippocampal sulcus Fimbria of hippocampus Dentate gyrus Rhinal sulcus Other Supracallosal gyrus Uncus Amygdala Insular cortex Insular cortex General Operculum Poles of cerebral hemispheres Some categorizations are approximations, and some Brodmann areas span gyri. Retrieved from `` https://en.wikipedia.org/w/index.php?title=Cerebral_hemisphere&oldid=801110901 '' Categories : Cerebrum Human physiology Talk Contents About Wikipedia Català Čeština Eesti Ελληνικά Español Esperanto فارسی Français Bahasa Indonesia Basa Jawa Magyar Nederlands Polski Português Română Suomi ไทย Türkçe Українська اردو Edit links This page was last edited on 17 September 2017, at 18 : 42. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: the large commissure that connects the cerebral hemisphere is
Answer: corpus callosum