{"id":3282,"date":"2025-04-06T08:02:10","date_gmt":"2025-04-06T08:02:10","guid":{"rendered":"https:\/\/www.europesays.com\/uk\/3282\/"},"modified":"2025-04-06T08:02:10","modified_gmt":"2025-04-06T08:02:10","slug":"serotonin-signals-the-brains-best-guess-about-future-rewards","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/uk\/3282\/","title":{"rendered":"Serotonin Signals the Brain\u2019s Best Guess About Future Rewards"},"content":{"rendered":"<p><strong>Summary: <\/strong>A new study reveals that serotonin neurons in the brain may play a crucial role in helping us estimate the value of future rewards. Rather than simply responding to pleasure or pain, serotonin appears to encode a \u201cprospective value\u201d signal\u2014telling the brain how good the near future is likely to be.<\/p>\n<p>Using reinforcement learning models and neural recordings from serotonin-rich regions, researchers found these neurons respond most to unexpected rewards. This insight sheds new light on the complex role of serotonin in decision-making, learning, and emotion, potentially changing how we understand mood disorders and mental health treatments.<\/p>\n<p><strong>Key Facts:<\/strong><\/p>\n<ul class=\"wp-block-list\">\n<li><strong>Prospective Value Code:<\/strong> Serotonin neurons encode expected future rewards, not just pleasure or pain.<\/li>\n<li><strong>Surprise Matters:<\/strong> These neurons are especially activated by unexpected rewards.<\/li>\n<li><strong>Broad Implications:<\/strong> Findings could reshape understanding of decision-making and mental health treatments.<\/li>\n<\/ul>\n<p><strong>Source: <\/strong>University of Ottawa<\/p>\n<p><strong>In our day-to-day lives, we\u2019re constantly making a slew of decisions from immediate matters to prospects on the far horizon. <\/strong><\/p>\n<p>But the evolutionary nuts-and-bolts of how our brains weigh these numerous daily decisions and what role is played by the neurotransmitter serotonin has been shrouded in mystery.<\/p>\n<p>  <img fetchpriority=\"high\" decoding=\"async\" width=\"1200\" height=\"800\" src=\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/04\/serotonin-reward-prediction.jpg\" alt=\"This shows a brain.\"  \/> While the overall picture was extremely puzzling, he says it was then they realized they might be chasing something promising. Credit: Neuroscience News<\/p>\n<p>Now, a new study led by an interdisciplinary\u00a0uOttawa Faculty of Medicine\u00a0team delivers fascinating findings on this big topic and potentially unravels a hidden aspect of what our nervous system\u2019s extraordinarily complex serotonin system is really doing inside the enigmatic organ in our skulls.<\/p>\n<p>Published in the journal\u00a0Nature, this study from a highly impactful international collaboration was considered by one of the expert reviewers who evaluated the work to offer \u201cbroad implications across neuroscience, psychology, and psychiatry, enhancing our understanding of serotonin\u2019s role in mood regulation, learning, and motivated behavior.\u201d<\/p>\n<p>The team\u2019s innovative work merges ideas from reinforcement learning (RL) theory \u2013 used in neuroscience to better understand learning, behavior, and decision-making \u2013 with recent hard-won insights into the filtering properties of the brain\u2019s dorsal raphe nucleus. That\u2019s a region of the mammalian brainstem rich in serotonin-producing neurons.<\/p>\n<p>Serotonin is often painted as the brain\u2019s \u201cpleasure chemical.\u201d Antidepressant drugs such as selective serotonin reuptake inhibitors (SSRIs) famously target the serotonin system as part of a multi-billion-dollar industry.<\/p>\n<p>However, serotonin\u2019s precise role in the nervous system is ambiguous and perplexing: It\u2019s implicated in everything from mood and movement regulation to appetite and sleep-wake cycles. The fact that it\u2019s activated by pain, pleasure and surprise has long been a brain research puzzle.<\/p>\n<p>With this\u00a0study, the uOttawa-led researchers put forth a unifying perspective on serotonin they dub a \u201cprospective code for value\u201d \u2013 a biological code for how the brain places a value for future rewards.<\/p>\n<p>This code essentially explains why serotonin neurons are activated in the brain in response to both rewards and punishments, with a preference for surprising rewards.<\/p>\n<p>\u201cOur work asks the question: What does serotonin tell the brain? In a nutshell, we find that its message closely matches the expectation of future rewards,\u201d says\u00a0senior author Dr. Richard Naud, associate professor at the Faculty of Medicine\u2019s\u00a0Department of Cellular and Molecular Medicineand the uOttawa\u00a0Department of Physics.<\/p>\n<p>Co-author Dr. Jean-Claude B\u00e9\u00efque<strong>,<\/strong>\u00a0professor in the Department of Cellular and Molecular Medicine, puts the main findings like this: \u201cYour brain needs to compute the expected value of the actions you contemplate and undertake as you interact with a changing world, asking \u2018What\u2019s the value of this decision versus that decision in that particular environment?\u2019 That\u2019s a hard problem.<\/p>\n<p>\u201cSo what we think serotonin actually does in the brain is encode the expected value of a particular environment or course of actions in order to ultimately guide everyday decisions.\u201d<\/p>\n<p>Drs. B\u00e9\u00efque and Naud are both members of the\u00a0uOttawa Brain and Mind Research Institute\u2019s Centre for Neural Dynamics and Artificial Intelligence.<\/p>\n<p>About this neuroscience research news<\/p>\n<p class=\"has-background\" style=\"background-color:#ffffe8\"><strong>Author: <\/strong><a href=\"https:\/\/www.uottawa.ca\/en\/gazette-news\" target=\"_blank\" rel=\"noreferrer noopener\">Richard Naud<\/a><br \/><strong>Source: <\/strong><a href=\"https:\/\/www.uottawa.ca\/en\/gazette-news\" target=\"_blank\" rel=\"noreferrer noopener\">University of Ottawa<\/a><br \/><strong>Contact: <\/strong>Richard Naud \u2013 University of Ottawa<br \/><strong>Image: <\/strong>The image is credited to Neuroscience News<\/p>\n<p class=\"has-background\" style=\"background-color:#ffffe8\"><strong>Original Research: <\/strong>Closed access.<br \/>\u201c<a href=\"https:\/\/doi.org\/10.1038\/s41586-025-08731-7\" target=\"_blank\" rel=\"noreferrer noopener\">A prospective code for value in the serotonin system<\/a>\u201d by Richard Naud et al. Nature<\/p>\n<p><strong>Abstract<\/strong><\/p>\n<p><strong>A prospective code for value in the serotonin system<\/strong><\/p>\n<p>The in vivo responses of dorsal raphe nucleus serotonin neurons to emotionally salient stimuli are a puzzle. Existing theories centring on reward, surprise, salience\u00a0and uncertainty\u00a0individually account for some aspects of serotonergic activity but not others.<\/p>\n<p>Merging ideas from reinforcement learning theory\u00a0with recent insights into the filtering properties of the dorsal raphe nucleus, here we find a unifying perspective in a prospective code for value.<\/p>\n<p>This biological code for near-future reward explains why serotonin neurons are activated by both rewards and punishments, and why these neurons are more strongly activated by surprising rewards but have no such surprise preference for punishments\u2014observations that previous theories have failed to reconcile.<\/p>\n<p>Finally, our model quantitatively predicts in vivo population activity better than previous theories.<\/p>\n<p>By reconciling previous theories and establishing a precise connection with reinforcement learning, our work represents an important step towards understanding the role of serotonin in learning and behaviour.<\/p>\n","protected":false},"excerpt":{"rendered":"Summary: A new study reveals that serotonin neurons in the brain may play a crucial role in helping&hellip;\n","protected":false},"author":2,"featured_media":3283,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[215,105,219,220,1915,376,16,15,1916],"class_list":{"0":"post-3282","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-health","8":"tag-brain-research","9":"tag-health","10":"tag-neurobiology","11":"tag-neuroscience","12":"tag-reward","13":"tag-serotonin","14":"tag-uk","15":"tag-united-kingdom","16":"tag-university-of-ottawa"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@uk\/114289976548386622","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/3282","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/comments?post=3282"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/3282\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media\/3283"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media?parent=3282"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/categories?post=3282"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/tags?post=3282"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}