{"id":496,"date":"2015-10-15T14:47:13","date_gmt":"2015-10-15T14:47:13","guid":{"rendered":"http:\/\/www.blog-thebrain.org\/?p=1081"},"modified":"2022-01-04T19:50:13","modified_gmt":"2022-01-04T19:50:13","slug":"inhibitory-neurons-more-than-just-a-brake","status":"publish","type":"post","link":"https:\/\/www.blog-thebrain.org\/advanced\/2015\/10\/15\/inhibitory-neurons-more-than-just-a-brake\/","title":{"rendered":"Inhibitory Neurons: More Than Just a Brake"},"content":{"rendered":"<p><img decoding=\"async\" loading=\"lazy\" class=\"alignleft size-full wp-image-3822\" title=\"interneurones\" src=\"https:\/\/www.blog-lecerveau.org\/wp-content\/uploads\/interneurones.jpg\" alt=\"\" width=\"120\" height=\"132\" \/><\/p>\n<p>Neuroscientists have known that the brain contains <a href=\"https:\/\/www.thebrain.mcgill.ca\/flash\/i\/i_01\/i_01_cl\/i_01_cl_ana\/i_01_cl_ana.html#2\">glial cells<\/a> just as long as they have known that it contains neurons, but only in the past two or three decades have scientists discovered the actual importance of glial cells for communication within the brain. Similarly, neuroscientists have long known that between the large excitatory neurons of the cerebral cortex, there are a multitude of small inhibitory neurons. Once thought to act as simple \u201cbrakes\u201d on brain activity, these inhibitory neurons have gradually been found to display far more complex variations in their nature, <span style=\"color: #008080;\"><a href=\"https:\/\/www.blog-thebrain.org\/blog\/2012\/09\/22\/the-1001-faces-of-the-neuron\/\"><span style=\"color: #008080;\">form<\/span><\/a><\/span>, connectivity and function than was originally believed.<!--more--><\/p>\n<p>The brake metaphor is certainly not inaccurate. A dysfunction in certain of these interneurons can gradually cause the nerve impulses between the excitatory neurons to race out of control, resulting in a veritable electrical storm inside the brain: an epileptic seizure.<\/p>\n<p>Conversely, augmenting this natural brake on brain activity is one way to dampen certain \u201chigher\u201d functions that tend to get out of control and create all sorts of anxiety-producing scenarios in human beings. That is why some people take certain prescription tranquilizers (such as <span style=\"color: #008080;\"><a href=\"https:\/\/www.thebrain.mcgill.ca\/flash\/i\/i_03\/i_03_m\/i_03_m_par\/i_03_m_par_benzodiazepines.html#drogues\"><span style=\"color: #008080;\">benzodiazepines<\/span><\/a><\/span>) or consume non-prescription tranquilizers (such as <span style=\"color: #008080;\"><a href=\"https:\/\/www.thebrain.mcgill.ca\/flash\/i\/i_03\/i_03_m\/i_03_m_par\/i_03_m_par_alcool.html#drogues\"><span style=\"color: #008080;\">alcohol<\/span><\/a><\/span>) to help <span style=\"color: #ff9900;\"><a href=\"https:\/\/www.thebrain.mcgill.ca\/flash\/d\/d_04\/d_04_m\/d_04_m_peu\/d_04_m_peu.html#1\"><span style=\"color: #ff9900;\">calm themselves a bit<\/span><\/a><\/span>, or, in the case of alcohol (which despite being legal is still toxic in high doses) simply to \u201cuntie their tongues\u201d in social situations, All this basically means is that our social inhibitions, which are generally highly cortical, are partly alleviated by potentiation of these inhibitory neurons that use <span style=\"color: #008080;\"><a href=\"https:\/\/www.thebrain.mcgill.ca\/flash\/i\/i_01\/i_01_m\/i_01_m_ana\/i_01_m_ana.html#2\"><span style=\"color: #008080;\">GABA as a neurotransmitter<\/span><\/a><\/span>. And in fact, it is known that both benzodiazepine molecules and alcohol molecules bind to the excitatory neurons&#8217; <span style=\"color: #ff9900;\"><a href=\"https:\/\/www.thebrain.mcgill.ca\/flash\/d\/d_04\/d_04_m\/d_04_m_peu\/d_04_m_peu.html#2\"><span style=\"color: #ff9900;\">GABA receptors<\/span><\/a><\/span>, thus helping them to open. Since these channel receptors are permeable to negatively charged chlorine ions, they hyperpolarize the membranes of the excitatory neurons and thus make them less excitable.<\/p>\n<p>But as the website <em>Knowing Neurons<\/em> reported in November 2014 (see links below), in coverage that included an interview with Dr. Gordon J. Fishell, who studies inhibitory neurons, these neurons may play several other roles as well, especially in explaining affective disorders, some of them, once again, anxiety-related. For example, the connections between physical exercise, the neurogenesis of GABA neurons in the hippocampus, and the reduction of anxiety <span style=\"color: #008080;\"><a href=\"https:\/\/www.blog-lecerveau.org\/blog\/2013\/07\/15\/lexercice-regulier-un-remede-contre-lanxiete\/\"><span style=\"color: #008080;\">have been clarified by the work of Dr. Elizabeth Gould and her research team.<\/span><\/a><\/span><\/p>\n<p>Inhibitory neurons (also known as inhibitory interneurons, an allusion to their evolutionary origin, in which they appeared between the sensory and motor neurons) also appear to play an important role in helping to organize the entire network of cortical neurons during the development of the human embryo. How? Here&#8217;s where nature has yet another surprise in store for us: by depolarizing other neurons by sending them GABA which, later on, will have exactly the opposite effect on the mature neurons, hyperpolarizing them and thus distancing them from the threshold for triggering nerve impulses! One possible explanation for this seeming paradox is that the immature neurons may not have the same receptors as the mature ones.<\/p>\n<p><a href=\"http:\/\/knowingneurons.com\/2014\/11\/05\/inhibitory-neurons-keeping-the-brains-traffic-in-check\/\" target=\"_blank\" rel=\"noopener\"><span style=\"color: #008080;\"><img decoding=\"async\" loading=\"lazy\" style=\"border: 0pt;\" src=\"https:\/\/www.blog-lecerveau.org\/wp-content\/uploads\/i_lien.gif\" alt=\"i_lien\" width=\"15\" height=\"15\" \/> Inhibitory Neurons: Keeping the Brain&#8217;s Traffic in Check<\/span><\/a><br \/>\n<a href=\"http:\/\/knowingneurons.com\/2014\/11\/03\/science-fiction-serendipity-and-interneuron-specification-a-conversation-with-dr-gordon-j-fishell\/\" target=\"_blank\" rel=\"noopener\"><span style=\"color: #008080;\"><img decoding=\"async\" loading=\"lazy\" style=\"border: 0pt;\" src=\"https:\/\/www.blog-lecerveau.org\/wp-content\/uploads\/i_lien.gif\" alt=\"i_lien\" width=\"15\" height=\"15\" \/> Science Fiction, Serendipity and Interneuron Specification: A Conversation with Dr. Gordon J. Fishell<\/span><\/a><br \/>\n<a href=\"https:\/\/knowingneurons.files.wordpress.com\/2014\/11\/a-conversation-with-gordon-fishell1.pdf\" target=\"_blank\" rel=\"noopener\"><span style=\"color: #008080;\"><img decoding=\"async\" loading=\"lazy\" style=\"border: 0pt;\" src=\"https:\/\/www.blog-lecerveau.org\/wp-content\/uploads\/i_lien.gif\" alt=\"i_lien\" width=\"15\" height=\"15\" \/> A Conversation with Gordon Fishell<\/span><\/a><br \/>\n<a href=\"http:\/\/www.sfn.org\/annual-meeting\/neuroscience-2014\/sessions-and-events\/scientific-program\/featured-lectures#Presidential-Special-Lecture\" target=\"_blank\" rel=\"noopener\"><span style=\"color: #008080;\"><img decoding=\"async\" loading=\"lazy\" style=\"border: 0pt;\" src=\"https:\/\/www.blog-lecerveau.org\/wp-content\/uploads\/a_lien.gif\" alt=\"a_lien\" width=\"15\" height=\"15\" \/><span style=\"color: #ff0000;\"> The Integration of Interneurons Into Cortical Circuits: Both Nurture and Nature &#8211; Gordon J. Fishell<\/span><\/span><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Neuroscientists have known that the brain contains glial cells just as long as they have known that it contains neurons, but only in the past two or three decades have scientists discovered the actual importance of glial cells for communication within the brain. Similarly, neuroscientists have long known that between the large excitatory neurons of [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[10],"tags":[249,250],"_links":{"self":[{"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/posts\/496"}],"collection":[{"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/comments?post=496"}],"version-history":[{"count":2,"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/posts\/496\/revisions"}],"predecessor-version":[{"id":944,"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/posts\/496\/revisions\/944"}],"wp:attachment":[{"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/media?parent=496"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/categories?post=496"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.blog-thebrain.org\/advanced\/wp-json\/wp\/v2\/tags?post=496"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}