{"id":38119,"date":"2026-08-02T12:44:00","date_gmt":"2026-08-02T10:44:00","guid":{"rendered":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/?p=38119"},"modified":"2026-08-03T13:07:16","modified_gmt":"2026-08-03T11:07:16","slug":"science-que-se-passe-t-il-dans-le-cerveau-face-a-lincertitude","status":"publish","type":"post","link":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/2026\/08\/02\/science-que-se-passe-t-il-dans-le-cerveau-face-a-lincertitude\/","title":{"rendered":"[Science] Que se passe-t-il dans le cerveau face \u00e0 l\u2019incertitude ?"},"content":{"rendered":"<div class=\"paragraph\">\n<p>On savait que cette mol\u00e9cule \u00e9tait impliqu\u00e9e dans l\u2019adaptation du comportement. \u00ab\u00a0<i>Lorsqu\u2019on emp\u00eache sa production, les animaux ont tendance \u00e0 reproduire toujours le m\u00eame comportement<\/i><i>\u00a0<\/i>\u00bb, souligne J\u00e9r\u00e9mie Naud\u00e9. Mais cela manquait de pr\u00e9cision. Et surtout d\u2019un mod\u00e8le\u00a0: des \u00e9quations math\u00e9matiques qui d\u00e9criraient le taux de noradr\u00e9naline en fonction des changements constat\u00e9s.<\/p>\n<p>Erreurs \u00e0 ignorer<\/p>\n<p>Les chercheurs montrent ici que la noradr\u00e9naline temp\u00e8re le r\u00f4le de la dopamine \u2013 un autre neurotransmetteur. \u00ab\u00a0<i>Elle permet de faire la diff\u00e9rence entre des erreurs \u00e0 consid\u00e9rer ou \u00e0 ignorer<\/i><i>\u00a0<\/i>\u00bb, r\u00e9sume J\u00e9r\u00e9mie Naud\u00e9. Car la dopamine est lib\u00e9r\u00e9e proportionnellement \u00e0 l\u2019erreur constat\u00e9e. Et le changement de comportement sera d\u2019autant plus grand que l\u2019erreur est grande et la quantit\u00e9 de dopamine importante. \u00ab\u00a0<i>C\u2019est connu et utilis\u00e9 dans le mod\u00e8le standard d\u2019adaptation du comportement face au changement<\/i><i>\u00a0<\/i>\u00bb, pr\u00e9cise-t-il. La noradr\u00e9naline agit \u00e0 plus long terme. \u00ab\u00a0<i>Son taux varie en fonction des erreurs cons\u00e9cutives<\/i><i>\u00a0<\/i>\u00bb, poursuit le chercheur. Si les \u00e9carts par rapport \u00e0 l\u2019attendu sont positifs ou n\u00e9gatifs, il faut les ignorer car l\u2019environnement est al\u00e9atoire\u00a0: le taux de noradr\u00e9naline reste faible. Mais si les erreurs vont toujours dans le m\u00eame sens, il faut adapter son comportement car l\u2019environnement a chang\u00e9\u00a0: le taux de noradr\u00e9naline augmente.<\/p>\n<p>Ces r\u00e9sultats ont \u00e9t\u00e9 constat\u00e9s chez des rats pouvant actionner deux leviers\u00a0: l\u2019un offrait beaucoup de nourriture, l\u2019autre non. Et cela changeait, parfois de mani\u00e8re durable, parfois al\u00e9atoirement. \u00ab\u00a0<i>Nos coll\u00e8gues de Bordeaux, sous la direction d\u2019\u00c9tienne Coutureau, ont observ\u00e9 la quantit\u00e9 de noradr\u00e9naline lib\u00e9r\u00e9e gr\u00e2ce \u00e0 une mol\u00e9cule fluorescente<\/i><i>\u00a0<\/i>\u00bb, pr\u00e9cise J\u00e9r\u00e9mie Naud\u00e9. Puis a \u00e9t\u00e9 \u00e9tudi\u00e9 le comportement de rats chez qui la lib\u00e9ration de noradr\u00e9naline dans le cortex \u00e9tait bloqu\u00e9e. \u00ab\u00a0<i>Ils mettent plus de temps \u00e0 s\u2019adapter apr\u00e8s un changement durable<\/i><i>\u00a0<\/i>\u00bb, constate le chercheur. De quoi peut-\u00eatre aider \u00e0 comprendre certains troubles neuropsychiatriques&#8230; pourvu que ces r\u00e9sultats soient confirm\u00e9s chez l\u2019humain.<\/p>\n<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"L&rsquo;endroit est fameux pour p&ecirc;cher. Les poissons mordent &agrave; tous les coups. Seulement, un beau matin, la p&ecirc;che est moins bonne qu&rsquo;esp&eacute;r&eacute;e. Est-ce de la malchance et cela vaut quand m&ecirc;me le coup de &#8230;","protected":false},"author":1,"featured_media":38120,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3926,3924,20],"tags":[2780,572,416,1058,988,2001],"news-destination":[3944],"news-source":[475],"is_homepage":[],"ta_other":[],"class_list":["post-38119","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-accueil-merge","category-accueil-second","category-societe","tag-cerveau","tag-france","tag-recherche-scientifique","tag-science","tag-week-end","tag-weekend","news-destination-homepage","news-source-website"],"_links":{"self":[{"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/posts\/38119","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/comments?post=38119"}],"version-history":[{"count":2,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/posts\/38119\/revisions"}],"predecessor-version":[{"id":38327,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/posts\/38119\/revisions\/38327"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/media\/38120"}],"wp:attachment":[{"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/media?parent=38119"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/categories?post=38119"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/tags?post=38119"},{"taxonomy":"news-destination","embeddable":true,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/news-destination?post=38119"},{"taxonomy":"news-source","embeddable":true,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/news-source?post=38119"},{"taxonomy":"is_homepage","embeddable":true,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/is_homepage?post=38119"},{"taxonomy":"ta_other","embeddable":true,"href":"https:\/\/euapp01.newsmemory.com\/lamarseillaise\/news\/wp-json\/wp\/v2\/ta_other?post=38119"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}