Lateral Connectivity: Propagation of Network Belief and Hallucinatory-Like States in the Primary Visual Cortex

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Lateral Connectivity: Propagation of Network Belief and Hallucinatory-Like States in the Primary Visual Cortex Lateral connectivity : propagation of network belief and hallucinatory-like states in the primary visual cortex Benoît Le Bec To cite this version: Benoît Le Bec. Lateral connectivity : propagation of network belief and hallucinatory-like states in the primary visual cortex. Neuroscience. Sorbonne Université, 2018. English. NNT : 2018SORUS509. tel-03125268 HAL Id: tel-03125268 https://tel.archives-ouvertes.fr/tel-03125268 Submitted on 29 Jan 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Sorbonne Université Ecole doctorale Cerveau, Cognition et Comportement Thèse de Doctorat de Neuroscience Cognitive Benoît Le Bec Lateral connectivity: propagation of network belief and hallucinatory-like states in the primary visual cortex Thèse Dirigée par Yves Frégnac et Marc Pananceau Présentée et soutenue publiquement le : lundi 03 décembre 2018 Devant le Jury composé de : Dr. Laurent Perrinet Rapporteur Dr. Rufin VanRullen Rapporteur Dr. Jean-Marc Edeline Examinateur Pr. Stéphane Charpier Examinateur Dr. Yves Frégnac Directeur de thèse Dr. Marc Pananceau Co-directeur de thèse 2 “When you open your mind to the impossible, sometimes you find the truth...Based on our findings we developed a window of sorts, a way of looking into this neighboring world. This window works by capturing errant photons from the universe beside ours. The window essentially stretches the membrane between our worlds and allows us to see their image from our side...Geometry and harmonic vibrations, that’s how we did it, Belly and I. Send Belly’s Monte Carlo from this universe to the other side. As I’ve said before, the two universes vibrate at different frequencies so we set up three harmonic rods arranged as an equilateral triangle and then we activated the rods. When the car began to vibrate at just the right frequency—that’s how we sent Belly’s car to the other side...I designed a device intended to cross the time-space continuum and retrieve my dying son...This is the boy I showed you, the other Peter. It was the only way I could save him...Elizabeth, don't. He's not ours. I have to take him back...I realized at that moment that despite what I'd promised, what I fully intended to do, that I could never take Peter back. The way she looked at him. I saw in her what I feared most in myself when I saw him: I couldn't lose him again. It was the first hole, Olivia. The first breach. The first crack in the pattern of cracks. Spaces between the worlds. And it's my fault. You can't imagine what it's like to lose a child...You and I both know there are certain things we take for granted. The laws of nature, for example that are not necessarily binding. There are places on this Earth where two plus two most definitely does not equal four. You figured out how to bend time. But you're only interested in traveling to the past. Your goal, your next jump, is the 18th of May....Then allow me to serve as a precautionary tale. There will be repercussions if you pull Arlette from that car. You don't know how things will be changed by your actions, but they will. It's not our place to adjust the universe. And you will never be able to look at her again without knowing that, just like every time I look at my son. I have traveled through madness to figure this out. And you will too.” Walter Bishop, Fringe 3 4 Remerciements - Acknowledgements Il n’est jamais aisé de trouver des mots pour retranscrire souvenirs et émotions d’une portion de vie. Le langage semble bien souvent insuffisant pour en refléter l’étendue. Si j’ai bien appris quelque chose lors de ces années de thèse, c’est qu’il n’existe pas de voie toute tracée ; contrairement aux idéaux naïfs du néophyte, je crois que nous ne pouvons que tenter de faire de notre mieux, continuellement, et que c’est déjà beaucoup. Il est donc venu le temps pour moi de refermer un chapitre, de tourner une page. Le vingt-trois décembre deux mille treize qui marque le début de cette histoire, mon frère et moi partîmes en voiture de notre Bretagne natale pour que j’aille visiter l’Unic. Après plus de trois heures de discussion avec Yves Frégnac, nous nous serrâmes la pogne et je rentrai chez moi pour Noël sous vent de tempête avec une idée en tête : faire une thèse en neuroscience. Je remercie tout d’abord les membres de mon jury : Laurent Perrinet et Rufin VanRullen pour leur accessibilité et l’intérêt qu’ils ont porté à ce travail en acceptant d’être rapporteurs de ma thèse, Stéphane Charpier pour sa disponibilité et sa gentillesse ainsi que Jean-Marc Edeline dont la bienveillance, le calme et la curiosité scientifique m’ont toujours inspiré. Je remercie également Jean Lorenceau pour ses précieux conseils et son accompagnement lors de ma thèse. Je remercie Yves Frégnac pour m’avoir accueilli au sein de son laboratoire, pour m’avoir donné ma chance et pour m’avoir fait confiance. Yves, tu m’as laissé les coudées franches en t’assurant que j’étais entouré d’un noyau solide pour avancer. Je crois que ce qui me marquera le plus sont tes arrivées au labo, suivies du fameux « réunion en salle de vie dans cinq minutes ». C’est seulement couche par couche, pas à pas, que j’ai progressivement découvert ton univers de recherche. Richesse qui vient de l’intérieur, que l’on parle de l’Unic intra-muros ou d’une cellule. C’est ton recul scientifique, nourri par ton goût de la rigueur étymologique qui m’inspire le plus grand respect, et sans lequel ma thèse ne serait pas ce qu’elle est aujourd’hui. Tu as su m’aider, m’encourager et me soutenir pendant l’écriture du manuscrit. En tout cela trouve mon amitié et un grand merci ! Marc, il y’a tellement de choses à dire… Que ce soit ta gentillesse ou les fous rires…C’est bien simple, sans toi, je ne connaitrais rien de l’intra. Je garde précieusement en mémoire les moments de délire ou, à quatre heures du mat, on empale une cellule sur du David Gilmour. Des choses qui m’impressionnent le plus chez toi, je retiens ton humilité et ta pédagogie. Combien de fois nous ne nous sommes pas retrouvés en manip à attendre ton retour providentiel, après lequel ni une ni deux, on retrouve espoir. Pour toutes les discussions également, passionnées, endiablées, you are the star ! Merci pour tes conseils, ta compréhension et ta présence dans les moments difficiles. De tes blagues répétées sur le chouchen, je garde le rythme et j’enchaîne. De toi, je garde l’image que tu m’as donnée : celle d’une goutte d’eau qui coule, déroule, toujours vers l’aval ! La première fois aperçue, dit-on, dans une rivière de Durtal. J’en viens maintenant à toi Chris, mon collègue de bureau, mon binôme. Qu’est-ce qu’on a pu en voir tous les deux ! Toujours sur le pont du lundi au dimanche, toujours avec ta joie de vivre, ton envie de voir le verre à moitié plein. C’est en grande partie grâce à toi que j’ai tenu toutes ces années, 5 sans aucun doute. Non seulement tu m’as épaulé, mais tu m’as également porté par moments. Ta souplesse d’esprit, ton empathie et la finesse de tes analyses ont réellement fait de toi le cœur de notre esprit d’équipe, contre vents et marées. Un baroudeur kayakiste qui bricole de ses mains, chercheur, véto, anesthésiste qui d’un seul geste esquisse le travail de demain. Ce qui frappe le plus dans ta manière d’enseigner n’est pas la certitude de ce que tu assènes, mais la façon dont tu distribues les clés qui permettront de te convaincre. Prendre l’air, discuter avec toi de tout et de rien, je n’aurais pu rêver d’un meilleur voisin ! Merci à toi Xoana pour les moments passés ensemble. Comme tu l’as dit, travailler de nuit, ça crée des liens ! Tantôt à la rame, tantôt à la proue, on a souqué ferme pour aller jusqu’au bout. De toi je garde l’extrême rigueur scientifique, l’analyse, l’argumentation. Je crois que j’ai appris auprès de toi plus que je ne m’en rends compte. De la Galice à paris tu as fait beaucoup de chemin. Maintenant que ta voile tend vers de nouveaux horizons, le meilleur pour toi et les tiens ! Gérard, sans toi cette section aurait peu de sens puisqu’elle n’existerait probablement pas. J’ai découvert en toi tout un monde qui s’exprime davantage par les actes que par la parole. Et puis j’ai commencé à envahir ton bureau, venant te voir de plus en plus, apprenant. Tu es la personne qui a donné un sens à ma thèse, me fournissant chaque jour de nouveaux buts, des objectifs à atteindre quand ma boussole n’indiquait plus le nord. En un tour de main, l’air de rien, toujours avec tact et sans jamais un mot plus haut que l’autre, j’ai bien vite compris la nécessité d’écouter et d’observer pour plonger de plus en plus profondément dans ta logique de la programmation.
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