?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Mixing+Memory+and+Desire%3A+Want+and+Will+in+Neural+Modeling&rft.creator=MacLennan%2C+Bruce+J.&rft.subject=Behavioral+Neuroscience&rft.subject=Animal+Cognition&rft.subject=Theoretical+Biology&rft.subject=Cognitive+Psychology&rft.subject=Computational+Neuroscience&rft.subject=Artificial+Intelligence&rft.subject=Neural+Nets&rft.subject=Robotics&rft.subject=Neural+Modelling&rft.subject=Epistemology&rft.description=Values+are+critical+for+intelligent+behavior%2C+since+values+determine+interests%2C+and+interests+determine+relevance.+Therefore+we+address+relevance+and+its+role+in+intelligent+behavior+in+animals+and+machines.+Animals+avoid+exhaustive+enumeration+of+possibilities+by+focusing+on+relevant+aspects+of+the+environment%2C+which+emerge+into+the+(cognitive)+foreground%2C+while+suppressing+irrelevant+aspects%2C+which+submerge+into+the+background.+Nevertheless%2C+the+background+is+not+invisible%2C+and+aspects+of+it+can+pop+into+the+foreground+if+background+processing+deems+them+potentially+relevant.+Essential+to+these+ideas+are+questions+of+how+contexts+are+switched%2C+which+defines+cognitive%2Fbehavioral+episodes%2C+and+how+new+contexts+are+created%2C+which+allows+the+efficiency+of+foreground%2Fbackground+processing+to+be+extended+to+new+behaviors+and+cognitive+domains.+Next+we+consider+mathematical+characterizations+of+the+foreground%2Fbackground+distinction%2C+which+we+treat+as+a+dynamic+separation+of+the+concrete+space+into+(approximately)+orthogonal+subspaces%2C+which+are+processed+differently.+Background+processing+is+characterized+by+large+receptive+fields+which+project+into+a+space+of+relatively+low+dimension+to+accomplish+rough+categorization+of+a+novel+stimulus+and+its+approximate+location.+Such+background+processing+is+partly+innate+and+partly+learned%2C+and+we+discuss+possible+correlational+(Hebbian)+learning+mechanisms.+Foreground+processing+is+characterized+by+small+receptive+fields+which+project+into+a+space+of+comparatively+high+dimension+to+accomplish+precise+categorization+and+localization+of+the+stimuli+relevant+to+the+context.+We+also+consider+mathematical+models+of+valences+and+affordances%2C+which+are+an+aspect+of+the+foreground.+Cells+processing+foregound+information+have+no+fixed+meaning+(i.e.%2C+their+meaning+is+contextual)%2C+so+it+is+necessary+to+explain+how+the+processing+accomplished+by+foreground+neurons+can+be+made+relative+to+the+context.+Thus+we+consider+the+properties+of+several+simple+mathematical+models+of+how+the+contextual+representation+controls+foreground+processing.+We+show+how+simple+correlational+processes+accomplish+the+contextual+separation+of+foreground+from+background+on+the+basis+of+differential+reinforcement.+That+is%2C+these+processes+account+for+the+contextual+separation+of+the+concrete+space+into+disjoint+subspaces+corresponding+to+the+foreground+and+background.+Since+an+episode+may+comprise+the+activation+of+several+contexts+(at+varying+levels+of+activity)+we+consider+models%2C+suggested+by+quantum+mechanics%2C+of+foreground+processing+in+superposition.+That+is%2C+the+contextual+state+may+be+a+weighted+superposition+of+several+pure+contexts%2C+with+a+corresponding+superposition+of+the+foreground+representations+and+the+processes+operating+on+them.+This+leads+us+to+a+consideration+of+the+nature+and+origin+of+contexts.+Although+some+contexts+are+innate%2C+many+are+learned.+We+discuss+a+mathematical+model+of+contexts+which+allows+a+context+to+split+into+several+contexts%2C+agglutinate+from+several+contexts%2C+or+to+constellate+out+of+relatively+acontextual+processing.+Finally%2C+we+consider+the+acontextual+processing+which+occurs+when+the+current+context+is+no+longer+relevant%2C+and+may+trigger+the+switch+to+another+context+or+the+formation+of+a+new+context.+We+relate+this+to+the+situation+known+as+%22breakdown%22+in+phenomenology.&rft.publisher=Lawrence+Erlbaum%2C+Mahwah&rft.contributor=Pribram%2C+Karl+H.&rft.date=1998&rft.type=Conference+Paper&rft.type=NonPeerReviewed&rft.format=application%2Fpostscript&rft.identifier=http%3A%2F%2Fcogprints.org%2F84%2F2%2FMMD.ps&rft.identifier=++MacLennan%2C+Bruce+J.++(1998)+Mixing+Memory+and+Desire%3A+Want+and+Will+in+Neural+Modeling.++%5BConference+Paper%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F84%2F