From Basic Network Principles to Neural Architecture: Emergence of Orientation-Selective CellsRalph Linsker doi:10.1073/pnas.83.21.8390 1986;83;8390-8394 PNAS This information is current as of December 2006. www.pnas.org#otherarticlesThis article has been cited by other articles: E-mail Alerts. click hereright corner of the article orReceive free email alerts when new articles cite this article - sign up in the box at the top Rights & Permissions www.pnas.org/misc/rightperm.shtmlTo reproduce this article in part (figures, tables) or in entirety, see: Reprints www.pnas.org/misc/reprints.shtmlTo order reprints, see: Notes:Proc.Nati.Acad.Sci.USAVol.83,pp.8390-8394,November1986NeurobiologyFrombasicnetworkprinciplestoneuralarchitecture:Emergenceoforientation-selectivecells*(modularself-adaptivenetworks/visualsystem/feature-analyzingcells)RALPHLINSKERIBMThomasJ.WatsonResearchCenter,YorktownHeights,NY10598CommunicatedbyRichardL.Garwin,July7,1986ABSTRACTThisisthesecondpaperinaseriesofthreethatexplorestheemergenceofseveralprominentfeaturesofthefunctionalarchitectureofvisualcortex,ina"modularself-adaptivenetwork"containingseverallayersofcellswithparallelfeedforwardconnectionswhosestrengthsdevelopaccordingtoaHebb-typecorrelation-rewardingrule.InthepresentpaperIshowthatorientation-selectivecells,similartothe"simple"corticalcellsofHubelandWiesel[Hubel,D.H.&Wiesel,T.N.(1962)J.Physiol.160,106-154],emergeinsuchanetwork.Noorientationpreferenceisspecifiedtothesystematanystage,theorientation-selectivecelllayeremergesevenintheabsenceofenvironmentalinputtothesystem,andnoneofthebasicdevelopmentalrulesisspecifictovisualprocessing.Inthisseriesofpapers,Ishowthatmanyobservedfeaturesofthefunctionalarchitectureofmammalianvisualcortexemergeinasimplesystemconsistingofseverallayersofcellsdevelopingundertheinfluenceofaconnection-modificationrule(e.g.,ofHebbtype).Paper1(1)showedtheemergenceofspatial-opponentcellsinathree-layersystemwithparallelfeedforwardconnectionsonlyandwithrandomspontaneousactivity(noenvironmentalinputneeded)inthefirstlayer.In thepresentpaper,Iextendthenetworkofpaper1byaddingmorelayerstothesystemandretainingthesamedevelopmentruleusedinpaper1.Ishowthatwhenasetofuncorrelatedactivitiesisrandomlygeneratedinthefirstlayer(layerA)ofthesystemandprocessedbythematureA-to-Band(opponent-type)B-to-Cconnectionswhoseemergentpropertieswerederivedinpaper1,thelayer-Cactivitydisplaysspatialstructure.Thatis,theactivitiesofapairofcellsinlayerCarecorrelatedoverdistancesoftheorderofthearborizationbreadthoftheB-to-Cconnections.Further,theparticular("Mexican-hat")formofthistwo-pointautocorrelationfunctionleadstotheemergenceoforienta-tion-selectivecellsinlaterlayersofthesystem.Thesecells'receptivefieldpropertiesaresimilartothoseofthe"simple"cellsofHubelandWiesel(2).Orientation-SelectiveCells.Orientation-selectivecellsor-ganizedinto"columns"-bandlikeregionsofcellsofthesameorsimilarorientation-arefoundinalllayersexceptIVaandIVcofarea17inmacaquemonkey(3,4),andhavealsobeendescribedincatandothermammaliansystems.Inmacaque,thesecellsandorganizationarisepriortoanyvisualexperience(4).Severalsuggestionshavebeenmadeconcerningtheoriginandorganizationoforientation-selectivecells.(i)Anisotro-piesinretinalanatomy(e.g.,in cat)mightsomehowinducehorizontalandverticalorientationpreferencesinspecificgroupsoffibers(5),orgroupsoforientation-specificfiberscanbepostulatedabinitio(6),andalateral-inhibitionmechanismcanbeinvokedto"fillin"theintermediateorientations.(ii)Inputfromothersystems(e.g.,vestibular)couldsomehowplayaroleintheformationoforientation-selectivecells.(iii)Foramodelenvironmentconsistingofbarpatternsatallorientations,centeredoneatatimeoveracellwhoseinputsarearrangedtoformaring,andwithanassumedmechanismthatforcesthecelltodiscriminateamongpatterns,ithasbeenfoundthattheresponseofthecellbecomestunedtoaparticularorientationpreference(7). (iv)Certaincellsmayserveasorganizingcentersthatinducetheformationoforientation-selectivecellswithaparticulardispositionofpreferredorientations,accountingfortheobservedcolumnararrangement(8).Thesepreviousstudieshavecontributedtoaframeworkforthinkingabouttheconditionsunderwhichorientation-selectivecellsmightform.Theyhavenot,however,pro-ducedanexplicittheoryofhow(orwhether)orientation-selectivecellscanform-eitherinarealisticvisualenviron-mentorintheabsenceofvisualinput-withoutsomehowspecifyingatleastsomeorientationpreferencestothesystemattheoutset.Thepresentpaperisconcernedwiththefollowingques-tions.Canalayeroforientation-selectivecellsemergeintheabsenceofvisualexperience,withnobuilt-inanisotropiesororientationpreferencesandwithnoinputfromothersystemsthatmaybeinteractingwiththeexternalenvironment?Inparticular,doessuchacelllayeremergeinamodular(layered)self-adaptivenetwork(1)governedbysomesimple,biologicallyplausiblerulesforsynapticmodificationandforthebasicstructureofanetwork,andgiven onlyspontaneouselectricalactivity(noenvironmentalinteraction)?Ifitdoes,doesitsformationdependuponpreciselychosenconditions,oruponqualitativefeaturesthatarerathergeneral?METHODSGrossArchitectureandDevelopmentRule.Thegrossar-chitectureofoursystemisthatofpaper1,extendedtoadditionallayersD,E,.
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