{"id":3057,"date":"2020-12-13T21:24:13","date_gmt":"2020-12-13T19:24:13","guid":{"rendered":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/neurohistology\/spinal-cord\/internal-organization-of-the-spinal-cord\/"},"modified":"2020-12-13T22:14:15","modified_gmt":"2020-12-13T20:14:15","slug":"internal-organization-of-the-spinal-cord","status":"publish","type":"page","link":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/","title":{"rendered":"Internal Organization of the Spinal Cord"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">We can divide both the gray and white matter of the spinal cord into regions, and more specifically nuclei and laminae (gray mater laminae or Laminae of Rexed).<\/p>\n\n\n<span class=\"block-heading\" id=\"header_1\">\n<h3 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title1\">The internal organization of the gray matter<\/h3>\n<\/span><span class=\"block-content\" id=\"contents_1\">\n\n\n<p class=\"wp-block-paragraph\">These laminae are defined on the basis of neuronal size, shape, cytological features and density, and are numbered in a dorsoventral sequence.<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><a href=\"http:\/\/meddists.com\/wp-content\/uploads\/2019\/01\/1280px-Medulla_spinalis_-_Substantia_grisea_-_English.svg1_.png\" target=\"_blank\" title=\"Internal Organization of the Spinal Cord\" target=\"_blank\" rel=\"noreferrer noopener\"><img decoding=\"async\" src=\"http:\/\/meddists.com\/wp-content\/uploads\/2019\/01\/1280px-Medulla_spinalis_-_Substantia_grisea_-_English.svg1_-600x441.png\" alt=\"\" class=\"wp-image-8754\"\/><\/a><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Gray matter laminae of the spinal cord&nbsp;<\/strong>&#8212; Polarlys &#8212; CC BY-SA 4.0<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><strong>Lamina I (posteromarginal nucleus)<\/strong> \u2013 Contains small neuronal cells (<strong>Waldeyer\u2019s neurons<\/strong>), the region of pain (<strong>nociceptive<\/strong>)<\/li><li><strong>Lamina II (substantia gelatinosa)<\/strong> \u2013 Contains small neurons, primary afferent fibers, also for pain (nociceptive)<\/li><li><strong>Lamina III (nucleus proprius)<\/strong> \u2013 Medium-sized antenna cells with dendrites that penetrate lamina II<\/li><li><strong>Lamina IV (nucleus proprius)<\/strong> \u2013 Big sized antenna cells that receive information from lamina II. Gives rise to the ascending Spinothalamic pathway<\/li><li><strong>Lamina V<\/strong> <strong>and VI <\/strong>\u2013 Deep, small and medium-sized cells, mainly interneurons<\/li><li><strong>Lamina VII (zona intermedia) <\/strong>\u2013 Quite different, can be subdivided into different segments of the spinal cord:<ul><li>Nucleus intermediomedialis \u2013 Integrative<\/li><li>Nucleus intermediolateralis \u2013 Visceromotor, located at thoracolumbar and sacral parts<\/li><li>Nucleus cervicalis centralis (C1-C4) \u2013 Special sensory<\/li><li>Dorsal thoracic nucleus (Clarke\u2019s column, T8-L2) &#8212; Primary afferent, the origin of the spinocerebellar tract<\/li><\/ul><\/li><li><strong>Lamina VIII <\/strong>\u2013 Located at the ventral (anterior) horn. Contains mostly interneurons, forms commissural nucleus at the lumbar segment<\/li><li><strong>Lamina IX<\/strong> \u2013 Occupies the biggest part of the ventral horn. Big motor neurons are found with a strict pattern<\/li><li><strong>Lamina X <\/strong>\u2013 Around the central canal, the reticular formation of the spinal cord<\/li><\/ul>\n\n\n<\/span><span class=\"block-heading\" id=\"header_2\">\n<h3 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title1\">The internal organization of the white matter<\/h3>\n<\/span><span class=\"block-content\" id=\"contents_2\">\n\n\n<p class=\"wp-block-paragraph\">In a similar way that we classify the gray matter, we can classify the white matter. However, here we refer to the regions by their common pathways throughout the spinal cord \u2013 <strong>tracts<\/strong>. Each pathway or tract has an origin and a destination.<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><a href=\"http:\/\/meddists.com\/wp-content\/uploads\/2018\/02\/Screenshot_52.png\" target=\"_blank\" title=\"Internal Organization of the Spinal Cord\" target=\"_blank\" rel=\"noreferrer noopener\"><img decoding=\"async\" src=\"http:\/\/meddists.com\/wp-content\/uploads\/2018\/02\/Screenshot_52-1024x438.png\" alt=\"\" class=\"wp-image-2074\"\/><\/a><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Spinal cord tracts<\/strong>&nbsp;&#8212; By&nbsp;Polarlys and Mikael H\u00e4ggstr\u00f6m &#8212; CC BY-SA 4.0<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Even though these tracts belong to neuroanatomy, and are not part of the neurohistology course, you might want to study the most frequently asked ones.<\/p>\n\n\n<\/span><span class=\"block-heading\" id=\"header_3\">\n<h4 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title2\">Ascending tracts<\/h4>\n<\/span><span class=\"block-content\" id=\"contents_3\">\n\n\n<p class=\"wp-block-paragraph\"><strong>Dorsal columns of the medial lemniscus<br><\/strong>The dorsal column consists of two large ascending tracts \u2013 the <strong>gracile fasciculus<\/strong> and the <strong>cuneate fasciculus<\/strong>.<br>These contain a high proportion of myelinated fibers carrying <strong>proprioceptive<\/strong> (position awareness), <strong>exteroceptive<\/strong> (touch-pressure) and vibratory sensation to higher levels.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Spinocerebellar tracts<br><\/strong>There are two spinocerebellar tracts \u2013 dorsal (posterior) and ventral (anterior). Both tracts convey proprioceptive and exteroceptive information, but they are functionally different<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Spinothalamic tracts<br><\/strong>The spinothalamic tracts consist of second-order neurons that convey pain, temperature, coarse touch and pressure information to the somatosensory region of the thalamus.<\/p>\n\n\n<\/span><span class=\"block-heading\" id=\"header_4\">\n<h4 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title2\">Descending tracts<\/h4>\n<\/span><span class=\"block-content\" id=\"contents_4\">\n\n\n<p class=\"wp-block-paragraph\">Concerned with the control of movement, muscle tone, and posture, the modulation of spinal reflex mechanisms and the transmission of afferent information to higher levels. They also mediate control over spinal autonomic neurons.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The tracts are named accordingly to the region of origin in the brain (olivospinal, vestibulospinal etcetera).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Comma tract of Schultze (not shown above)<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Located around the posterior median sulcus, it is a compact bundle composed of descending branches of posterior root fibers located near the border between the fasciculi gracilis and cuneatus of the cervical and thoracic spinal cord.<\/p>\n<\/span><div id=\"the_titles\" style=\"display:none;\"><h3 class=\"wp-block-heading\" class=\"wp-block-heading\">The internal organization of the gray matter<\/h3><h3 class=\"wp-block-heading\" class=\"wp-block-heading\">The internal organization of the white matter<\/h3><h4 class=\"wp-block-heading\" class=\"wp-block-heading\">Ascending tracts<\/h4><h4 class=\"wp-block-heading\" class=\"wp-block-heading\">Descending tracts<\/h4><\/div>","protected":false},"excerpt":{"rendered":"<p>We can divide both the gray and white matter of the spinal cord into regions, and more specifically nuclei and laminae (gray mater laminae or Laminae of Rexed). The internal organization of the gray matter These laminae are defined on the basis of neuronal size, shape, cytological features and density, and are numbered in a [&hellip;]<\/p>\n","protected":false},"author":23,"featured_media":0,"parent":3031,"menu_order":2,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-3057","page","type-page","status-publish","hentry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.8 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Internal Organization of the Spinal Cord &#8211; Meddists<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"3 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/spinal-cord\\\/internal-organization-of-the-spinal-cord\\\/\",\"url\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/spinal-cord\\\/internal-organization-of-the-spinal-cord\\\/\",\"name\":\"Internal Organization of the Spinal Cord &#8211; Meddists\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/spinal-cord\\\/internal-organization-of-the-spinal-cord\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/spinal-cord\\\/internal-organization-of-the-spinal-cord\\\/#primaryimage\"},\"thumbnailUrl\":\"http:\\\/\\\/meddists.com\\\/wp-content\\\/uploads\\\/2019\\\/01\\\/1280px-Medulla_spinalis_-_Substantia_grisea_-_English.svg1_-600x441.png\",\"datePublished\":\"2020-12-13T19:24:13+00:00\",\"dateModified\":\"2020-12-13T20:14:15+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/spinal-cord\\\/internal-organization-of-the-spinal-cord\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/spinal-cord\\\/internal-organization-of-the-spinal-cord\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/spinal-cord\\\/internal-organization-of-the-spinal-cord\\\/#primaryimage\",\"url\":\"http:\\\/\\\/meddists.com\\\/wp-content\\\/uploads\\\/2019\\\/01\\\/1280px-Medulla_spinalis_-_Substantia_grisea_-_English.svg1_-600x441.png\",\"contentUrl\":\"http:\\\/\\\/meddists.com\\\/wp-content\\\/uploads\\\/2019\\\/01\\\/1280px-Medulla_spinalis_-_Substantia_grisea_-_English.svg1_-600x441.png\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/spinal-cord\\\/internal-organization-of-the-spinal-cord\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"http:\\\/\\\/meddists.com\\\/learn\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Pre-clinical\",\"item\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Histology\",\"item\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/\"},{\"@type\":\"ListItem\",\"position\":4,\"name\":\"Nervous system\",\"item\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/\"},{\"@type\":\"ListItem\",\"position\":5,\"name\":\"Spinal Cord\",\"item\":\"https:\\\/\\\/meddists.com\\\/learn\\\/pre-clinical\\\/histology\\\/nervous-system\\\/spinal-cord\\\/\"},{\"@type\":\"ListItem\",\"position\":6,\"name\":\"Internal Organization of the Spinal Cord\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/#website\",\"url\":\"https:\\\/\\\/meddists.com\\\/learn\\\/\",\"name\":\"Meddists\",\"description\":\"Let&#039;s Get Studying\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/meddists.com\\\/learn\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Internal Organization of the Spinal Cord &#8211; Meddists","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/","twitter_misc":{"Est. reading time":"3 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/","url":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/","name":"Internal Organization of the Spinal Cord &#8211; Meddists","isPartOf":{"@id":"https:\/\/meddists.com\/learn\/#website"},"primaryImageOfPage":{"@id":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/#primaryimage"},"image":{"@id":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/#primaryimage"},"thumbnailUrl":"http:\/\/meddists.com\/wp-content\/uploads\/2019\/01\/1280px-Medulla_spinalis_-_Substantia_grisea_-_English.svg1_-600x441.png","datePublished":"2020-12-13T19:24:13+00:00","dateModified":"2020-12-13T20:14:15+00:00","breadcrumb":{"@id":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/#primaryimage","url":"http:\/\/meddists.com\/wp-content\/uploads\/2019\/01\/1280px-Medulla_spinalis_-_Substantia_grisea_-_English.svg1_-600x441.png","contentUrl":"http:\/\/meddists.com\/wp-content\/uploads\/2019\/01\/1280px-Medulla_spinalis_-_Substantia_grisea_-_English.svg1_-600x441.png"},{"@type":"BreadcrumbList","@id":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/internal-organization-of-the-spinal-cord\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"http:\/\/meddists.com\/learn\/"},{"@type":"ListItem","position":2,"name":"Pre-clinical","item":"https:\/\/meddists.com\/learn\/pre-clinical\/"},{"@type":"ListItem","position":3,"name":"Histology","item":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/"},{"@type":"ListItem","position":4,"name":"Nervous system","item":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/"},{"@type":"ListItem","position":5,"name":"Spinal Cord","item":"https:\/\/meddists.com\/learn\/pre-clinical\/histology\/nervous-system\/spinal-cord\/"},{"@type":"ListItem","position":6,"name":"Internal Organization of the Spinal Cord"}]},{"@type":"WebSite","@id":"https:\/\/meddists.com\/learn\/#website","url":"https:\/\/meddists.com\/learn\/","name":"Meddists","description":"Let&#039;s Get Studying","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/meddists.com\/learn\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"}]}},"_links":{"self":[{"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages\/3057","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/users\/23"}],"replies":[{"embeddable":true,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/comments?post=3057"}],"version-history":[{"count":1,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages\/3057\/revisions"}],"predecessor-version":[{"id":3096,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages\/3057\/revisions\/3096"}],"up":[{"embeddable":true,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages\/3031"}],"wp:attachment":[{"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/media?parent=3057"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}