{"id":808669,"date":"2026-08-10T06:04:11","date_gmt":"2026-08-10T06:04:11","guid":{"rendered":"https:\/\/www.newsbeep.com\/us\/808669\/"},"modified":"2026-08-10T06:04:11","modified_gmt":"2026-08-10T06:04:11","slug":"long-covid-patients-have-18-fewer-dopamine-nerve-endings-brain-scans-reveal-sciencealert","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us\/808669\/","title":{"rendered":"Long COVID Patients Have 18% Fewer Dopamine Nerve Endings, Brain Scans Reveal : ScienceAlert"},"content":{"rendered":"<p> <a href=\"https:\/\/www.sciencealert.com\/coronavirus\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73041\" data-postid=\"212523\" rel=\"nofollow noopener\" target=\"_self\">COVID-19<\/a> can cause brain injuries that are still visible on scans years later in people with neurological symptoms related to long COVID.<\/p>\n<p>Existing research shows that cognitive dysfunction in long COVID is associated with <a href=\"https:\/\/www.nature.com\/articles\/s41593-024-01576-9\" rel=\"nofollow noopener\" target=\"_blank\">blood-brain barrier disruption<\/a>, an <a href=\"https:\/\/journals.plos.org\/plosone\/article?id=10.1371\/journal.pone.0316625\" rel=\"nofollow noopener\" target=\"_blank\">enlarged hippocampus<\/a>, <a href=\"https:\/\/www.nature.com\/articles\/s41591-024-03309-8\" rel=\"nofollow noopener\" target=\"_blank\">elevated brain injury markers<\/a>, and <a href=\"https:\/\/www.nature.com\/articles\/s41586-022-04569-5\" rel=\"nofollow noopener\" target=\"_blank\">reduced brain volume<\/a> on  <a href=\"https:\/\/www.sciencealert.com\/magnetic-resonance-imaging\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73063\" data-postid=\"212523\" rel=\"nofollow noopener\" target=\"_self\">MRI<\/a> scans.\u00a0<\/p>\n<p>Now, researchers in Canada have shown that people who experienced persistent apathy and  <a href=\"https:\/\/www.sciencealert.com\/depression\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73097\" data-postid=\"212523\" rel=\"nofollow noopener\" target=\"_self\">depression<\/a> for the first time in their lives a few months after a COVID-19 infection <a href=\"https:\/\/doi.org\/10.1016\/j.ebiom.2026.106369\" rel=\"nofollow noopener\" target=\"_blank\">have around 18 percent fewer dopamine nerve endings<\/a> in their brain than healthy people.\u00a0<\/p>\n<p><a href=\"https:\/\/my.clevelandclinic.org\/health\/articles\/22581-dopamine\" rel=\"nofollow noopener\" target=\"_blank\">Dopamine<\/a> is a neurotransmitter that helps control movement and motivation, and the loss of nerve endings that signal with dopamine affects cognitive function and can drive the <a href=\"https:\/\/www.sciencealert.com\/a-hidden-brain-process-may-help-explain-why-alzheimers-risk-rises-with-age\" rel=\"nofollow noopener\" target=\"_blank\">development of neurodegenerative diseases<\/a>.<\/p>\n<p>For their study published in <a href=\"https:\/\/doi.org\/10.1016\/j.ebiom.2026.106339\" rel=\"nofollow noopener\" target=\"_blank\">eBioMedicine<\/a>, the team analyzed positron emission tomography (PET) scans of the brains of 24 adults with long COVID and 24 healthy adults of a similar age.<\/p>\n<p>They measured the loss of dopamine nerve endings in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Striatum\" rel=\"nofollow noopener\" target=\"_blank\">striatum<\/a>, a region in the center of the brain that controls movement and motivation.<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/08\/1786341849_630_0.jpg\" alt=\"YouTube Thumbnail\" tabindex=\"0\" role=\"button\" class=\"youtube-thumbnail-preview\" loading=\"lazy\"\/> frameborder=&#8221;0\u2033 allow=&#8221;accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share&#8221; referrerpolicy=&#8221;strict-origin-when-cross-origin&#8221; allowfullscreen&gt;<\/p>\n<p>Participants were injected with a radiotracer that binds to a protein expressed by dopamine-signaling nerves, called <a href=\"https:\/\/en.wikipedia.org\/wiki\/Vesicular_monoamine_transporter_2\" rel=\"nofollow noopener\" target=\"_blank\">vesicular monoamine transporter 2<\/a> (VMAT2).\u00a0<\/p>\n<p>VMAT2 is a well-established biomarker used in neurodegenerative conditions such as  <a href=\"https:\/\/www.sciencealert.com\/go\/IYl\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73029\" data-postid=\"212523\" rel=\"nofollow noopener\" target=\"_self\">Parkinson&#8217;s<\/a> disease.\u00a0<\/p>\n<p>The PET scans showed that loss of dopamine nerve endings in the <a href=\"https:\/\/www.sciencealert.com\/researchers-think-they-ve-found-the-brain-region-directly-responsible-for-happy-feelings\" rel=\"nofollow noopener\" target=\"_blank\">ventral striatum<\/a> was linked with lower motivation<\/p>\n<p>In the dorsal striatum, loss of dopamine nerve endings in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Putamen\" rel=\"nofollow noopener\" target=\"_blank\">putamen<\/a> was associated with moving slower and taking longer to complete tasks, and loss in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Caudate_nucleus\" rel=\"nofollow noopener\" target=\"_blank\">caudate nucleus<\/a> was tied to memory decline and a struggle to recall words.<\/p>\n<p>The damage to the dopamine nerve endings was present in people who had been living with long COVID for up to 4.6 years.\u00a0<\/p>\n<p>While the number of patients in this study may be small, it&#8217;s a particularly arresting finding in that these changes were detectable on brain scans. In other words, they are visible.<\/p>\n<p>&#8220;What cannot be seen is too often considered uncertain,&#8221; nuclear medicine researcher Eric Guedja and neuroscientist Danielle Beckman <a href=\"https:\/\/doi.org\/10.1016\/j.ebiom.2026.106369\" rel=\"nofollow noopener\" target=\"_blank\">write<\/a> in a commentary about the study.<\/p>\n<p>&#8220;Liu and colleagues report a PET study that translates a clinically elusive neuropsychiatric phenotype of long COVID into a measurable dopaminergic signal.&#8221;<\/p>\n<p><img decoding=\"async\" width=\"973\" height=\"675\" src=\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/08\/Screenshot-2026-08-06-at-2.52.22-pm-973x675.png\" alt=\"Some People With Long COVID Have Fewer Dopamine Signals in Their Brain\" class=\"wp-image-212528\"   loading=\"lazy\"\/>People with long COVID had lower levels of a tracer that binds to dopamine nerve endings than healthy people. Healthy people who had been infected with COVID-19 had fewer dopamine nerve endings than healthy people who had not been infected with the  <a href=\"https:\/\/www.sciencealert.com\/virus\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73053\" data-postid=\"212523\" rel=\"nofollow noopener\" target=\"_self\">virus<\/a>.\u00a0(Lui et al., eBioMedicine, 2026)<\/p>\n<p>The marker of nerve damage used in the study could potentially be used to diagnose long COVID, Jeffrey Meyer, a neurochemist at the University of Toronto, told ScienceAlert.\u00a0<\/p>\n<p>Some people with long COVID might respond to &#8220;treatments which either increase the density of dopamine nerve terminals or improve the release of dopamine by the remaining dopamine nerve terminals&#8221;, said Meyer.\u00a0<\/p>\n<p>In an upcoming  <a href=\"https:\/\/www.sciencealert.com\/clinical-trials\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73032\" data-postid=\"212523\" rel=\"nofollow noopener\" target=\"_self\">clinical trial<\/a>, Meyer and his team will repurpose a medication that influences dopamine to see if it helps with long COVID symptoms. This work is patented by the hospital conducting the research, the Centre for Addiction and Mental Health, and Meyer is the inventor of that patent.\u00a0<\/p>\n<p>There is a <a href=\"https:\/\/www.nature.com\/articles\/s41579-022-00846-2\" rel=\"nofollow noopener\" target=\"_blank\">dire need<\/a> for validated, evidence-based treatments and <a href=\"https:\/\/www.nejm.org\/doi\/full\/10.1056\/NEJMsb2408466\" rel=\"nofollow noopener\" target=\"_blank\">tests<\/a> for long COVID, as none currently exist. The disease is managed by <a href=\"https:\/\/www.sciencedirect.com\/science\/article\/pii\/S1836955326000160\" rel=\"nofollow noopener\" target=\"_blank\">treating symptoms<\/a> or through <a href=\"https:\/\/www.rthm.com\/pdfs\/long-covid-treatment-guide.pdf\" rel=\"nofollow noopener\" target=\"_blank\">trial and error<\/a> with repurposed medications.<\/p>\n<p>Many people <a href=\"https:\/\/doi.org\/10.1186\/s12913-023-10170-x\" rel=\"nofollow noopener\" target=\"_blank\">go without treatment<\/a> because they cannot access specialist care or are offered <a href=\"https:\/\/www.meresearch.org.uk\/research\/nice-criteria\/\" rel=\"nofollow noopener\" target=\"_blank\">ineffective, outdated, and sometimes harmful<\/a> options, such as graded exercise therapy or cognitive behavioral therapy, that do not treat the underlying pathologies.<\/p>\n<p><a href=\"https:\/\/www.sciencealert.com\/newsletter?int_promo=stargazing\" rel=\"nofollow noopener\" target=\"_blank\"><img decoding=\"async\" width=\"642\" height=\"336\" src=\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/05\/FOMO-1200x628-_Dont-miss-the-next-breakthrough_-cosmic-colourful-642x336.jpg\" alt=\"Subscribe to ScienceAlert's free fact-checked newsletter\" class=\"wp-image-201722\"   loading=\"lazy\"\/><\/a><\/p>\n<p>It&#8217;s not known exactly how many people develop long COVID after an acute COVID-19 infection because estimates vary, but it ranges between <a href=\"https:\/\/doi.org\/10.1016\/j.ebiom.2026.106339\" rel=\"nofollow noopener\" target=\"_blank\">2 percent<\/a> and <a href=\"https:\/\/www.nature.com\/articles\/s41579-022-00846-2\" rel=\"nofollow noopener\" target=\"_blank\">10 percent<\/a> of the infected population.<\/p>\n<p>At least <a href=\"https:\/\/www.nature.com\/articles\/s41579-022-00846-2\" rel=\"nofollow noopener\" target=\"_blank\">65 million<\/a> people worldwide have long COVID, including <a href=\"https:\/\/jamanetwork.com\/journals\/jamapediatrics\/fullarticle\/2834486\" rel=\"nofollow noopener\" target=\"_blank\">10\u201320 percent<\/a> of children with a history of COVID-19.<\/p>\n<p>Related: <a href=\"https:\/\/www.sciencealert.com\/strange-structures-found-lurking-in-the-blood-of-people-with-long-covid\" rel=\"nofollow noopener\" target=\"_blank\">Strange Structures Found Lurking in The Blood of People With Long COVID<\/a><\/p>\n<p>The debilitating illness <a href=\"https:\/\/www.nature.com\/articles\/s41579-022-00846-2\" rel=\"nofollow noopener\" target=\"_blank\">affects<\/a> multiple organ systems and is associated with more than 200 symptoms, <a href=\"https:\/\/www.nature.com\/articles\/s41582-026-01205-y\" rel=\"nofollow noopener\" target=\"_blank\">including<\/a> fatigue, memory issues, sleep disorders, concentration impairment, dizziness, orthostatic intolerance, sensory overload, post-exertional malaise, headaches, anxiety, depression, and gastrointestinal issues.\u00a0<\/p>\n<p>It often leads to potentially lifelong conditions such as dysautonomia, cardiovascular disease,  <a href=\"https:\/\/www.sciencealert.com\/chronic-fatigue-syndrome\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73056\" data-postid=\"212523\" rel=\"nofollow noopener\" target=\"_self\">myalgic encephalomyelitis<\/a>\/ <a href=\"https:\/\/www.sciencealert.com\/chronic-fatigue-syndrome\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73056\" data-postid=\"212523\" rel=\"nofollow noopener\" target=\"_self\">chronic fatigue syndrome<\/a> (ME\/CFS), postural orthostatic tachycardia syndrome (POTS),  <a href=\"https:\/\/www.sciencealert.com\/diabetes\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73018\" data-postid=\"212523\" rel=\"nofollow noopener\" target=\"_self\">diabetes<\/a>, and mast cell activation syndrome (MCAS).<\/p>\n<p>&#8220;We need to find biological changes in long COVID that plausibly account for symptoms, and then develop treatments to address the biological changes in people with long COVID who have these symptoms,&#8221; said Meyer.\u00a0<\/p>\n<p>This paper was published in <a href=\"https:\/\/doi.org\/10.1016\/j.ebiom.2026.106339\" rel=\"nofollow noopener\" target=\"_blank\">eBioMedicine<\/a>.<\/p>\n<p>This article was fact-checked by <a href=\"https:\/\/www.sciencealert.com\/clare-watson\" rel=\"nofollow noopener\" target=\"_blank\">Clare Watson<\/a> and edited by <a href=\"https:\/\/www.sciencealert.com\/rebecca-dyer\" rel=\"nofollow noopener\" target=\"_blank\">Rebecca Dyer<\/a>. While we pride ourselves on our process, we are only human. If you spot a mistake, <a href=\"https:\/\/www.sciencealert.com\/contact-us\" rel=\"nofollow noopener\" target=\"_blank\">please let us know<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"COVID-19 can cause brain injuries that are still visible on scans years later in people with neurological symptoms&hellip;\n","protected":false},"author":2,"featured_media":808670,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[34],"tags":[97,1352],"class_list":["post-808669","post","type-post","status-publish","format-standard","has-post-thumbnail","category-health","tag-health","tag-msft-content"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/808669","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/comments?post=808669"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/808669\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media\/808670"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media?parent=808669"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/categories?post=808669"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/tags?post=808669"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}