<html><body><div style="font-family: arial, helvetica, sans-serif; font-size: 12pt; color: #000000"><div data-marker="__QUOTED_TEXT__"><div style=""><div style=""><div style=""><br><div style=""><div style=""><div style=""><div style=""><div style=""><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="font-size:16pt;font-family:'calibri'">Séminaire</span></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="font-size:16pt;font-family:'calibri'"> <span style="font-size:24pt">Neuromathématiques</span></span><span style="font-family:'calibri';font-size:20pt;text-indent:0cm"> </span></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><br></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-style:normal;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important">Organisé par</span></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-style:normal;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important">Giovanna Citti </span><i style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 )">(University of Bologna)</i></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-style:normal;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important">JP Nadal (<i style="color:rgb( 0 , 0 , 0 );font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;background-color:rgb( 255 , 255 , 255 )">CAMS - EHESS)</i></span></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-style:normal;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important">Jean Petitot</span><i style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 )"> (CAMS - EHESS)</i></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-style:normal;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important">Jerome Ribot </span><em style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 )">(Collège de France)</em><em style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 )"></em></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-style:normal;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important">Alessandro Sarti </span><i style="color:rgb( 0 , 0 , 0 );font-family:'times new roman' , 'new york' , 'times' , serif;font-size:17.3333px;font-weight:400;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 )">(CAMS - EHESS/CNRS) (reférent) </i></p><p align="center" style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif; font-size: 12pt; text-indent: 0cm; margin: 0px; text-align: center;"><span style="color:rgb( 0 , 0 , 0 );font-family:'times';font-size:10pt"><br></span></p><p align="center" style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif; font-size: 12pt; text-indent: 0cm; margin: 0px; text-align: center;"><span style="color:rgb( 0 , 0 , 0 );font-family:'times';font-size:10pt"></span><span style="text-align:center;text-indent:0px;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important"><font face="calibri"><span style="font-size:18.6667px"> mardi 11 mars 16h00-18h00 <---------</span></font></span></p><p align="center" style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif; font-size: 12pt; text-indent: 0cm; margin: 0px; text-align: center;"><span style="text-align:center;text-indent:0px;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important"><font face="calibri"><span style="font-size:18.6667px"><br data-mce-bogus="1"></span></font></span></p><p align="center" style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif; font-size: 12pt; text-indent: 0cm; margin: 0px; text-align: center;"><span style="text-align:center;text-indent:0px;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important"><span style="color:rgb( 0 , 0 , 0 );font-family:'calibri';font-size:18.6667px">Le séminaire sera en visioconference mais on se retrouve quand même </span></span></p><p align="center" style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif; font-size: 12pt; text-indent: 0cm; margin: 0px; text-align: center;"><span style="text-align:center;text-indent:0px;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important"><span style="color:rgb( 0 , 0 , 0 );font-family:'calibri';font-size:18.6667px">Salle D2.2, </span></span><span style="color:rgb( 0 , 0 , 0 );font-family:'calibri';font-size:14pt"><strong>Collège de France</strong>, 11, Place Marcelin-Berthelot, 75005, Paris</span></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; text-indent: 0cm; margin: 0px; text-align: center;"><span style="font-size:14pt;font-family:'calibri'">On se retrouve à l'accueille à 15h45 et on y va à la salle tous ensemble</span></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; text-indent: 0cm; margin: 0px; text-align: center;"><span style="font-size:14pt;font-family:'calibri'"><br data-mce-bogus="1"></span></p><p align="center" style="text-indent: 0cm; margin: 0px; text-align: center;"><font face="calibri"><span style="font-size: 18.6667px;">Lien Zoom: https://cnrs.zoom.us/j/98805698217?pwd=htpWZ24hdCoiWQfPgAjyzhjWZi6ZeE.1</span></font></p><p align="center" style="text-indent: 0cm; margin: 0px; text-align: center;"><br data-mce-bogus="1"></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; text-indent: 0cm; margin: 0px; text-align: center;"><span style="font-size:12pt;font-family:'calibri'">______________ </span><span style="font-size:10pt;font-family:'times'"></span></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; text-indent: 0cm; margin: 0px; text-align: center;"><br></p><div style="text-align: center;"><div dir="ltr" style=""><div dir="ltr" style="color: rgb(0, 0, 0); font-family: times; font-size: 14px;"><span style="font-size:24pt"><strong>Dario Ringach</strong></span><br></div><div dir="ltr" style="color: rgb(0, 0, 0); font-family: times; font-size: 14px;"><br></div><div dir="ltr" style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif; font-size: 12pt;"><strong style="color:rgb( 0 , 0 , 0 );font-family:'arial' , 'helvetica' , sans-serif;font-size:12pt"><span style="font-family:'times'"><span style="font-size:16pt"> University of California Berkeley </span></span></strong></div><div dir="ltr" style="color: rgb(0, 0, 0); font-family: times; font-size: 14px;"><span style="font-size:14pt"><strong> </strong></span></div><div dir="ltr" style="color: rgb(0, 0, 0); font-family: times; font-size: 14px;"><span style="font-size:14pt"><strong><br></strong></span></div><div dir="ltr" style=""><div class="" style=""><p style="margin: 0px;"><font face="times"><span style="font-size: 24px;"><b><i>Efficient Coding in Visual Cortex</i></b></span></font></p><p style="color: rgb(0, 0, 0); font-family: times; font-size: 14px; margin: 0px;"><br></p><div class="page" title="Page 1" style=""><div style="text-align: center;"><div class="column" style=""><div class="page" title="Page 1" style=""><div class="layoutArea" style=""><div class="" style="text-align: left;"><div class="" style="">I will describe experiments in the primary visual cortex that test fundamental principles of sensory representation, focusing on how populations of neurons efficiently encode the retinal image. First, we examine the dynamics of a sparsification network, inspired by Olshausen & Field’s work on sparse coding. We show that stimulus onset initially triggers widespread cortical activation, reducing sparseness and increasing mutual information. As activity declines due to competitive interactions, sparseness increases while mutual information remains sustained. Notably, coding efficiency—quantified as the ratio of mutual information to metabolic cost—progressively increases, demonstrating an adaptive optimization of sensory representations over time.</div><div class="" style="">Second, we describe a power law of adaptation, where the population response magnitude follows a power-law relationship with stimulus probability. We show how this power law emerges naturally from an efficient coding framework in which the neural population adapts to enhance both stimulus detection and discrimination while minimizing overall neural activity.</div><div class="" style="">Together, these findings illustrate the explanatory power of efficient coding principles in understanding cortical function, revealing how neural populations dynamically optimize their responses to maximize information transmission while minimizing metabolic cost.</div><div style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif; font-size: 12pt;"><br></div></div><div class="" style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif; font-size: 12pt;"><br></div></div></div></div></div></div></div></div></div></div><div class="x11i5rnm xat24cr x1mh8g0r x1vvkbs xtlvy1s x126k92a" style="color: rgb(8, 8, 9); font-family: arial, helvetica, sans-serif; font-size: 15px; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; word-spacing: 0px; white-space: pre-wrap; margin: 0.5em 0px 0px; background-color: rgb(255, 255, 255);"><div dir="auto" style="font-family:inherit;text-align:center"><br></div></div><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="font-size:14pt"><span style="font-family:'times new roman' , 'new york' , 'times' , serif"><a href="https://enseignements.ehess.fr/2024-2025/ue/248?fbclid=IwZXh0bgNhZW0CMTAAAR0VCfF-dGa5d-qMex3Niqrdjt8E_JK9HXLWCQ3qxcuxT4PGyY0Dwpv63a8_aem_J065n_5VoHkTgXdejEhJsA" rel="nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer" style="background:rgb( 255 , 255 , 255 );font-style:normal;letter-spacing:normal;text-indent:0px;text-transform:none;word-spacing:0px;white-space:pre-wrap;text-decoration:none;list-style:none;margin:0px;border-style:none;padding:0px;border-width:0px;outline:none;font-weight:600;display:inline" target="_blank">https://enseignements.ehess.fr/2024-2025/ue/248</a></span><span style="font-family:'times new roman' , 'new york' , 'times' , serif"><span style="color:rgb( 0 , 0 , 0 );font-style:normal;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important"> </span></span><span style="font-family:'calibri'"><span style="color:rgb( 0 , 0 , 0 );font-family:'calibri';font-style:normal;letter-spacing:normal;text-align:center;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb( 255 , 255 , 255 );float:none;display:inline !important"></span></span></span></p><p align="center" style="color: rgb(0, 0, 0); font-family: "times new roman", "new york", times, serif; font-size: 12pt; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0cm; text-transform: none; word-spacing: 0px; white-space: normal; background-color: rgb(255, 255, 255); margin: 0px; text-align: center;"><span style="font-size:14pt;font-family:'calibri'"><span style="font-family:'times new roman' , 'new york' , 'times' , serif">Inscription au lien </span><a href="https://participations.ehess.fr/" rel="nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer" target="_blank">https://participations.ehess.fr/<br></a></span></p></div></div></div></div></div></div></div></div><br></div></div></body></html>