Volume 78
Unconscious Memory Representations in Perception. Processes and mechanisms in the brain
Edited by István Czigler and István Winkler
Provides a forum for scholars from different scientific disciplines and fields of knowledge who study consciousness in its multifaceted aspects. Thus the Series includes (but is not limited to) the various areas of cognitive science, including cognitive psychology, brain science, philosophy and linguistics. The orientation of the series is toward developing new interdisciplinary and integrative approaches for the investigation, description and theory of consciousness, as well as the practical consequences of this research for the individual in society.
From 1999 the Series consists of two subseries that cover the most important types of contributions to consciousness studies:
Series A: Theory and Method. Contributions to the development of theory and method in the study of consciousness; Series B: Research in Progress. Experimental, descriptive and clinical research in consciousness.
This book is a contribution to Series B.
Editor
Maxim I. Stamenov Bulgarian Academy of Sciences
Editorial Board
David J. ChalmersAustralian National University Axel Cleeremans
Université Libre de Bruxelles Gordon G. Globus
University of California Irvine Christof Koch
California Institute of Technology Stephen M. Kosslyn
Harvard University
Steven Laureys
University of Liège, Belgium George Mandler
University of California at San Diego John R. Searle
University of California at Berkeley Petra Stoerig
Processes and mechanisms in the brain
Edited by
István Czigler
Institute for Psychology, Hungarian Academy of Sciences/ Debrecen University, Hungary
István Winkler
Institute for Psychology, Hungarian Academy of Sciences/ University of Szeged, Hungary
John Benjamins Publishing Company
Amsterdam / PhiladelphiaLibrary of Congress Cataloging-in-Publication Data
Unconscious memory representations in perception : processes and mechanisms in the brain / edited by István Czigler, István Winkler.
p. cm. (Advances in Consciousness Research, issn 1381-589X ; v. 78) Includes bibliographical references and index.
1. Implicit memory. I. Czigler, István. II. Winkler, István. BF378.I55U53 2010
153.1’3--dc22 2009053346
isbn 978 90 272 5214 2 (Hb ; alk. paper) isbn 978 90 272 8835 6 (Eb)
© 2010 – John Benjamins B.V.
No part of this book may be reproduced in any form, by print, photoprint, microfilm, or any other means, without written permission from the publisher.
John Benjamins Publishing Co. · P.O. Box 36224 · 1020 me Amsterdam · The Netherlands John Benjamins North America · P.O. Box 27519 · Philadelphia pa 19118-0519 · usa
Contributors vii
Preface ix
1. Conscious an�� unconscious as�ects of �or�in�� �e�or��Consciousan��unconsciousas�ectsof�or�in���e�or�� 1
Amanda L. Gilchrist and Nelson Cowan
2. Mar�ersofa�areness?EEG�otentialsevo�e��b��faint an���as�e��events,�iths�ecialreferencetothe“attentionalblin�” 37 Rolf Verleger 3. Insearchforau��itor��objectre�resentations 71 István Winkler 4. Re�resentationofre��ularitiesinvisualsti�ulation:Event-relate�� �otentialsrevealtheauto�aticacquisition 107 István Czigler 5. Au��itor��learnin��inthe��evelo�in��brain 133
Minna Huotilainen and Tuomas Teinonen
6. Neuroco��utational�o��elsof�erce�tualor��anization 147
Susan L. Denham, Salvador Dura-Bernal, Martin Coath and Emili Balaguer-Ballester
7. Are��oulistenin��?Lan��ua��eoutsi��ethefocusofattention 179
Yury Shtyrov and Friedemann Pulvermüller
8. Unconscious�e�or��re�resentationsun��erl��in���usic-s��ntactic
�rocessin��an���rocessin��ofau��itor��o����balls 209
9. Onthe�s��cho�h��siolo����ofaesthetics:Auto�atican��controlle�� �rocessesofaesthetica��reciation 245 Thomas Jacobsen A��en��ix:Usin��electro�h��siolo����tostu����unconscious�e�or�� re�resentations 259 Alexandra Bendixen In��ex 273
Alexan��raBen��ixen InstituteforPs��cholo����I Universit��ofLei�zi�� Seebur��str.14-20 D-04103Lei�zi��,Ger�an�� alexan��ra.ben��ixen@uni-lei�zi��.��e A�an��aL.Gilchristan��NelsonCo�an De�art�entofPs��cholo��icalSciences 18McAlesterHall Universit��ofMissouri Colu�bia,MO65211USA Co�anN@�issouri.e��u IstvánCzi��ler InstituteforPs��cholo���� Hun��arianAca��e���ofSciences 1394Bu��a�est,P.O.Box398,Hun��ar�� czi��ler@co���s���h��.hu SusanL.Denha� CentreforTheoreticalan��Co��utational Neuroscience Universit��ofPl���outh Dra�eCircusPl���outhPL48AA,UK s��enha�@�l���outh.ac.u� MinnaHuotilainenan��Tuo�asTeinonen Universit��ofHelsin�i P.O.Box9(Siltavuoren�en��er20D) FIN-00014Universit��ofHelsin�i �inna.huotilainen@helsin�i.fi Tho�asJacobsen Ex�eri�entalPs��cholo����Unit Facult��ofHu�anitiesan��SocialSciences Hel�utSch�i��tUniversit�� Universit��oftheFe��eralAr�e�� ForcesHa�bur�� Holstenhof�e��85 22043Ha�bur��,Ger�an Jacobsen@hsu-hh.��e StefanKoelsch De�art�entofPs��cholo���� Pevense��Buil��in�� Universit��ofSussex Bri��hton,BN19QH,UK �oelsch@cbs.����.��e Yur��Sht��rovan��Frie��e�annPulver�üller Me��icalResearchCouncil,Co��nitionan�� BrainSciencesUnit 15ChaucerRoa�� Ca�bri����e,CB27EF,UK ��ur��.sht��rov@�rc-cbu.ca�.ac.u� RolfVerle��er De�art�entofNeurolo���� Universit��ofLübec� 23538Lübec�,Ger�an�� rolf.verle��er@neuro.uni-luebec�.��e IstvánWin�ler InstituteforPs��cholo���� Hun��arianAca��e���ofSciences H-1394Bu��a�est,P.O.Box398,Hun��ar�� i�in�ler@co���s���h��.hu
Thestu����of�rocessesun��erl��in��consciousex�erienceisatra��itionalto�icof �hiloso�h��,�s��cholo����,an��neuroscience.Incontrast,untilrecentl��,theroleof i��licit(non-conscious)�e�or��s��ste�snee��e��toestablishveri��ical�erce�-tionreceive���uchless��iscussion.With�an��ne�resultsan��noveltheoretical �o��else�er��in��inrecent��ears,itisti�etota�ealoo�atthestateofartin�s��-cholo����an��neuroscienceabouttherolenon-conscious�rocessesan���e�or�� re�resentations�la��in�erce�tion. Althou��hbehavioralstu��ies(e.��.�ri�in��)inco��nitive�s��cholo������iel��e�� in��irectevi��enceabout�an��ofthecharacteristicsofi��licit�e�or��re�resen-tations,co��nitiveneurosciencean��co��utational�o��elin��can�rovi��e�ore ��irectinsi��htsintothestructurean��contentsofthesere�resentationsan��the intovarious�rocessesrelate��tothe�.Thisboo��resentsseveral��ifferenta�- �roachesofthestu����ofi��licit�e�or��re�resentations,usin��both�s��cholo��i- cal,neurosciencean��co��utational�o��elin���etho��s,assessin��thesere�re-sentationsinrelativel��si��lesituations,suchas�erceivin����iscreteau��itor��an�� visualsti�ulusevents,as�ellasinhi��h-levelco��nitivefunctions,suchass�eech an���usic�erce�tionan��aestheticex�erience. Eachcha�terrevie�sa��ifferentto�ic,itstheoreticalan���ajore��irical issues.Alar��e�artoftheresultsrevie�e��inthisboo��ereobtaine��throu��h recor��in��event-relate��brain�otentials(ERP).ThisisbecauseERPsofferhi��h te��oralresolution,an��asaconsequence,the��aresensitivein��icatorsofthe ����na�ics of hu�an infor�ation �rocessin��. Non-ex�ert rea��ers are offere�� �ithana��en��ixtohel�toun��erstan��an��assesstheERP��atarevie�e��in thevariouscha�ters.Ho�ever,ERPs�rovi��eless�reciseinfor�ationre��ar��in�� thesourcesoftheobserve��neuralactivit��inthebrain.Therefore,anincreas-in�� a�ount of research utilizes �ore recent braini�a��thesourcesoftheobserve��neuralactivit��inthebrain.Therefore,anincreas-in�� �etho��s, such as functional�a��neticresonancei�a��in��(fMRI),�hoses�atialresolutionexcee�� thatoftheERPs.Althou��htheex�eri�ental�ara��i���suse��inbraini�a��-in��areoftennot��etashi��hl��s�ecificasthose�or�e��outthrou��hthe��earsin behavioralorERPresearch,so�eofthesestu��iesalrea����brou��htsi��nificant ne�insi��htsintothe�or�in��ofi��licit�e�ories.Co��ontoallcha�tersis
thea��roachthate��iricalevi��enceisevaluate��inter�sofitsi��ortanceto �o��elsofthe�rocessesun��erl��in��conscious�erce�tion.
Inthefirstcha�ter,Gilchrist and Cowanrevie�theroleof�or�in���e�or�� inconsciousas�ellasinnon-consciousco��nitive�rocessin��.Verleger’scha�ter ��iscussesERPco��onentsrelate��tosubjectiveex�eriencean��non-conscious �rocesses.Winkler su����eststhat�re��ictivere�resentationsofacousticre��ulari-tiesfor�thecoreofau��itor���erce�tualobjects,�hileDenham, Dura-Berna,
Coathand Balaguer-Ballester��escribeaneuroco��uationala��roachto�o��el the�rocessesun��erl��in���erce�tualobjects.Theroleofsensor���e�or��inau-to�aticvisualchan��e��etectionan���erce�tionis��iscusse��inCzigler’scha�ter.
Huotilainen and Teinonenfocusontheroleoflearnin��an��i��licit�e�or��in
�erce�tual ��evelo��ent. Shtyrov and Pulvermüller’s cha�ter ��escribes a novel �ara��i���forstu����in��the�e�or��re�resentationsinvolve��ins�eech�erce�-tion.The��evaluatetherelevanttheoriesinli��htoftheirresultsan���rovi��ene� insi��htsintothenon-conscious�rocessesun��erl��in��s�eech�erce�tion.Koelsch �resentsana��vance��theor��ofthe�erce�tionof�usicalstructure,e��hasizin�� theroleofnon-conscious�rocessesan��i��licit�e�or��re�resentations.Finall��, theroleofnon-consciousan��conscious�rocessesinaesthetica��reciationis ex�lore��inJacobsen’s cha�ter.IntheA��en��ix,Bendixen�rovi��esaconcise��e-scri�tionoftheERP�etho��. Insu��ar��,thisboo��rovi��esatheoreticalan��e��iricalovervie�ofthe variousto�icsofan��a��roachestothequestion:Whatistheroleofnon-con-scious�e�or��re�resentationsin�erce�tion? Wethan�Maxi�Sta�enovforhisinitiativean��sti�ulatin��a��vice.Zsuzsa ��’Albini’stechnicalhel�is��reatfull��ac�no�le����e��.Our�or��assu��orte��b�� theHun��arianResearchFun��(OTKA71600)an��theEuro�eanCo��unit��’s SeventhFra�e�or�Pro��ra��e(��rantn°231168–SCANDLE). IstvánCzi��leran��IstvánWin�ler Bu��a�est,Nove�ber2009
of working memory
A�an��aL.Gilchristan��NelsonCo�an
Universit��ofMissouri,Colu�bia,USA1.1 Working-memory models and consciousness
Asi��le(an��,alas,oversi��lifie��)histor��of�or�in���e�or���o��elshel�sto len���ers�ectivetothe�resenten��eavor.Geor��eMiller(1956)is��enerall��cre��-ite���ith�ic�in��offarenaissanceinthestu����ofte��orar���e�or��relate��to theconscious�in��,inhis�ublishe��s�eechontheli�itofte��orar���e�or��to “the�a��icalnu�berseven�lusor�inust�o”(thou��h�an��researchersfaile�� toun��erstan��hishu�orousintentin��escribin��a�a��icalnu�bersurroun��e�� b��confi��enceintervals).Shortl��after�ar��,Milleretal.(1960)coine��theter� working memoryto��escribethe�e�or��forcurrent��oalsan��as�alla�ountof infor�ationthatallo�sone’si��e��iate�lanstobecarrie��out.Several�o��els usin��so�ethin��li�ethis�or�in���e�or��conce�t�illno�be��escribe��. 1.1.1 Infor�ation-flo��o��els Broa��bent(1958)�ro�ose��aver��si��le�o��elof�e�or��thattoo�intoac-countthelatestevi��ence;inthat�o��el,alar��ea�ountofsensor��infor�ation �asenco��e��inate��orar��buffer(li�e�hatisno�calle���or�in���e�or��). Ho�ever,onl��as�all�ro�ortionofitever�a��eits�a��intotheli�ite��-ca�acit�� �artof�e�or��,�hereit�asanal��ze��an��cate��orize���iththebenefitofthevast a�ountofinfor�ationsave��inlon��-ter��e�or��,an��eventuall��a����e��tothat lon��-ter�ban�of�no�le����e.At�insonan��Shiffrin(1968)then��evelo�e��that sortof�e�or��fra�e�or�intoa�oreex�licit�o��elin�hich�athe�atical si�ulations�ere�a��eofthetransferofinfor�ationfro�onestoretoanother throu��henco��in��,retrieval,an��rehearsal�rocesses.
1.1.2 Multi-co��onent�o��els
Ba����ele�� an�� Hitch (1974) soon foun�� that this si��le treat�ent of �or�in�� �e�or���oul��not��o.Ina����itiontoinfor�ationte��oraril��hel��inafor�li�e- l��toberelate��toconsciousness(Ja�es1890),the��ar��ue��infavorofotherstor-a��efacultiesthato�erate��auto�aticall��,outsi��eofvoluntar��control.Broa��bent (1958)alrea����ha��conceive��ofsensor���e�or��that�a��,butsensor���e�or�� �asnotenou��h.There�assai��tobea�honolo��icall��-base��te��orar���e�or�� storethat�asvulnerabletointerferencefro�a����itionalverbalite�s,no�atter �hethertheirsource�asvisualorau��itor��.Si�ilarl��,there�asavisuo-s�atial te��orar���e�or��storeres�onsivetothes�atialla��outan��visualqualitiesof ite�s;intheor��,thisstore�oul��bevulnerabletointerferencefro�s�atialinfor-�ationevenifitssource�ereau��itor��.Ba����ele��(1986)laterthou��hthecoul����o �ithoutthecentralstoreor�ri�ar���e�or��entirel��;�hereasBa����ele��(2000) essentiall��restore��itinthefor�ofane�iso��icbuffer. 1.1.3 Activation-base���o��els Afor�of�o��elthat�illbeco�ethecenter�ieceofthischa�teristheacti-vation-base���o��el.Inthatsortof�o��el(An��erson1983;Co�an1988;Hebb 1949;Nor�an1968;Treis�an1964)ate��orar��for�ofstora��esuchas�or�in�� �e�or��isvie�e��notasase�aratelocationinthe�in��orbrain,butratherasa stateofactivationofso�eoftheinfor�ationinthelon��-ter��e�or��s��ste�. Hebb(1949)envisione��thisactivate���e�or��asacellasse�bl��thatconsiste�� ofaneuralfirin���atternoccurrin��re�eate��l��solon��asthei��eaitre�resente�� �asactive.Treis�an(1964)an��Nor�an(1968)��istin��uishe��bet�eensubli�i-nala�ountsofactivation,�hich�i��htinfluencebehaviorbutnotconsciousl��, an��su�rali�inala�ounts,�hichattracte��attentiontotheactivate��ite�,es-�eciall��ifit�as�ertinenttothe�erson’scurrent��oalsan��concerns.An��erson (1983)use��the�rocessofactivationasa�a��tobrin��lon��-ter��no�le����einto �or�in���e�or��. Theinstanceoftheactivation-base���o��elsthat�e�ill��iscussin�ost��e-tailistheonethatCo�an(1988,1999)��esi��ne��asa�a��toex�ress�hathe believe��tobe�no�nattheti�e.There�erea���ar��as�ectsofthebox-base�� �o��elsoftheti�e,suchasthe�ell-�no�nonesofAt�insonan��Shiffrin(1968) an��Ba����ele��(1986).These�o��els��i��notrea��il��ex�resstheassu��tionthat infor�ationco-existsinseveralfor�satonce.Sensor��infor�ationcanbeac- co��anie��b���orecate��oricalinfor�ationthatis��ra�nfro�lon��-ter��e�-or��into�or�in���e�or��.Forexa��le,theacoustic�ro�ertiesofas�eechsoun�� elicitthea��ro�riatesoun��cate��or��thatisstore��inlon��-ter��e�or��.Other
Co�an(1988,1999)re�resente��thisstateofaffairs�ithe�be����e���rocesses. Te��oraril��-activate��featuresof�e�or��caninclu��ebothsensor��an��abstract features.So�eofthesefeaturesbeco�eactiveenou��h,oractiveintheri��ht�a��, tobeco�e�artofthein��ivi��ual’scurrentfocusofattention,�hichisofli�ite�� ca�acit��.Thefocusofattentioniscontrolle��in�artvoluntaril��,an��in�artinvol- untaril��throu��hthebrain’sreactionstoabru�t�h��sicalchan��esintheenviron-�ent(suchasasu����enchan��einli��htin��oralou��noise). Intheori��inal�o��elofBroa��bent(1958),unatten��e��sensor��infor�ation �asfiltere��outsothatitfa��e��a�a���ithouteverreachin��theca�acit��-li�ite�� store.This�o��elbeca�euntenable�henit�asfoun��thatas�ectsofunatten��e�� soun��scanattractattention(as�henone’so�nna�eis�resente��;seeMora�� 1959)soTreis�an(1964)�ro�ose��thatthefilteronl��attenuate��,ratherthan co��letel��bloc�in��out,sensor��in�utthat�asunatten��e��.Potentiall���ertinent in�utcoul��stillresultinattentionbein��attracte��tothatin�ut.Co�an(1988) solve��this�roble�inanother�a��,b��in��icatin��thatallsensor��in�ut�a��e contact�ithlon��-ter��e�or��,but�ithextraactivationforthe��eliberatel��-at-ten��e��in�utortheabru�tl��-chan��in��in�utthatattractsattentioninvoluntaril��. Thisistheconverseofthefilterin��conce�t. Co�an(2001)su����este��thatthefocusofattentioninthee�be����e���ro- cess�o��elofCo�an(1988,1999)isli�ite��toabout4se�arateite�sinnor-�ala��ults.Thisleaveso�enthebasisofin��ivi��ual��ifferencesinca�acit��li�its. Co�anan��collea��eshavesu����este��thatthereisabasic��ifferencebet�eenin-��ivi��ualsan��a��e��rou�sinthesizeofthefocusofattention(Chenan��Co�an 2009a;Co�an2001;Co�anetal.2005,2009;Gilchristetal.2008,2009).Anal-ternativebasisofin��ivi��ual��ifferencesan��a��e��ifferences,stillin�ee�in���ith the�o��el,isthatin��ivi��ualsa��earto��ifferintheabilit��tocontrolorallocate attentionorexecutivefunction(En��leetal.1999;Mi��a�eetal.2001)or,�ore s�ecificall��,toinhibitirrelevantite�san���reventthe�fro�clutterin��u�the li�ite��-ca�acit��store(Lusti��etal.2007).These�ossibilitiesarenot�utuall�� exclusivean��bothofthe�areco��atible�iththebasice�be����e���rocesses �o��el.(In��ee��,forastructuralequation�o��elsi�ilartoEn��leetal.orMi��a�e etal.,seeCo�anetal.2005.) Co�an’se�be����e���rocess�o��elassu�esthatstora��ean���rocessin��both useattention,an��thatcertain�rocessin��challen��es�ustbe�e�tinchec�us- in��attentionalca�acit��thatother�isecoul��be��evote��tothete��orar��stor-a��eofinfor�ation.Thesechallen��esinclu��esti�ulithatelicitstron��habitual res�onses,an��irrelevant��istracters.In��ee��,recentresearchhassu����este��that �rocessin��,suchastonei��entification,caninterfere�ithver����ifferentstora��e, suchasthatofvisualarra��sofobjects(Stevanovs�ian��Jolicoeur2007);an��that,
conversel��,stora��e,suchasthatofverballistite�s,caninterfere�ithver����if-ferent�rocessin��,suchasthatinas�ee��e��,nonverbal,choicereactionti�etas� (Chenan��Co�an2009b).Itre�ainstobeseen�hetherattentionhol��s�ulti�le ite�satonce��irectl��or,alternativel��,isuse��torefreshite�soneatati�ebefore theiractivationislost(Barrouilletetal.2007). 1.1.4 Consciousan��unconscious�rocessin��in��ifferent�o��els Althou��hthese�o��els�ereconstructe���iththeai�ofex�lainin��behavior, the��alsosee�relevanttotheissueofconsciousness.Fi��ure1sho�sthreeofthe �o��els�ithourinter�retationof�hat,�ithineach�o��el,isli�el��tocorres�on�� toconsciousan��unconscious�rocesses.Fi��ure1A��e�ictstheori��inal�o��elof Broa��bent(1958).Inthat�o��el,inco�in��sti�ulationfro�theenviron�ent �assai��tobehel��inate��orar��store,orbuffer,an��to��ono�hereexce�tfor thes�alla�ountthatisenco��e��intotheli�ite��-ca�acit��buffer.Giventhatsen-sor���e�or��is�uchricherthan�hatin��ivi��ualscanre�ort(�hich�assho�n forau��itor��sti�ulib��Broa��benthi�self,a�on��others,an��forvisualsti�ulib�� S�erlin��1960),the�o��el�ustconsi��erthecontentsofthesensor��buffertobe unconscious.Li�e�ise,thevastinfor�ationinlon��-ter��e�or��coul��notall beinconsciousnessatthesa�eti�e.Itistheli�ite��-ca�acit��bufferthat�oul�� hol��thecontentsofconsciousa�areness. Fi��ure1Bsho�sthe�o��elofBa����ele��(2000).Ba����ele��’s�o��els,eversince Ba����ele��an��Hitch(1974),i��licitl��haveassu�e���oreauto�atic�rocessin�� than�as�a��eclearb��Broa��bent(1958).In�articular,theentr��ofinfor�a-tionintothe�honolo��icalan��visuo-s�atialbuffersissai��tooccurauto�aticall��, resultin��inrea����-to-useco��es.These,ho�ever,nee��notbeinconsciousness. Forexa��le,Ba����ele��(1986)su��arize��researchin��icatin��thatunatten��e�� s�eechcoul��interfere�ith�or�in���e�or��for�rinte���or��s,��iventhat�ho- nolo��icalco��esarein�e�or��forbotht���esofsti�ulusatonce,lea��in��tocor-ru�tionofthe�aterialtobere�e�bere��.Incontrast,thee�iso��icbuffer,�hich �asa����e��tothe�o��elb��Ba����ele��(2000)inor��ertoaccountforte��orar�� �no�le����eofabstractfeatures,see�s�oreli�el��tobelin�e��toconsciousa�are- ness.Althou��htoour�no�le����eBa����ele��hasnotstate��as�uch,abstractinfor-�ationhasthea��vanta��ethatitcoul��refertoan��sti�ulus.Consciousnesssee�s tohavethequalit��ofunit��inthatoursubjectiveex�eriencesaresuchthatthere isonl��one�oolofconsciousness;forexa��le,if�eareloo�in��ata�or�ofart an��listenin��toatour��ui��e’s��escri�tionofit,�efeelconsciousofthe�or�of art,theverbal��escri�tion,an���erha�sthetour��ui��eallatonce.IntheBa����ele�� (2000)�o��el,theonl��bufferca�ableofre�resentin��an��inter-relatin��allofthis infor�ationisthee�iso��icbuffer.
A�ore��ifficult,thorn��issueis�hether�eareconsciousofcentralexecutive functions.Thesearefunctions��rivenb���otivationsan��intentions,asonecan tellb��testin��in��ivi��ualsun��er��ifferentsetsofinstructionsorre�ar��contin-��encies.Thecentralexecutiveis,b����efinition,thesetof�echanis�sres�onsible for�lannin��,sche��ulin��,an��executin��infor�ation�rocessin��thattransfor�s co��esinbuffersan���e�or��stores,affects�hatinfor�ationisatten��e��,an�� affects�hatactionsare�erfor�e��.Althou��h�eareatleastt���icall��a�areof theite�sto�hichattentionhasbeen��irecte��an��theite�sthatarebein��trans-for�e��fro�oneco��etoanotheror,inthe�arlanceofthe�o��el,shuttle��fro� Figure 1. A��e�ictionofthree�o��elsof�or�in���e�or��an��infor�ation�rocessin��, an��thestatus�e�resu�eforeachco��onentofeach�o��el�ithres�ecttoitsinclu-sioninconsciousa�areness(conscious)orexclusionfro�it(unconscious).Where�e ��i��nothavea�resu��tionone�a��ortheother,�ea����e��aquestion�ar�.Thearro�s co�in��fro�theleft-han��si��eofeachfi��urere�resenttheentr��ofsensor��infor�ation intoco��onentsofthes��ste�assho�n.A.Broa��bent’searl��-filter�o��el.B.Ba����ele��’s �ultico��onent�o��el.C.Co�an’se�be����e��-�rocesses�o��el. Sensory Buffer (Un-conscious) Filter (?) Capacity-limited Buffer (Conscious) Long-term Memory (Un-conscious) B. Baddeley (2000) Model Visuo-spatial Buffer (Un-conscious)
Central Executive Processes (?)
Long-Term Store (Unconscious) Phonological Buffer (Un-conscious) Episodic Buffer (Conscious)
Central Executive Processes (?)
C. Cowan (1988, 1999) Model Long-term memory (Un-conscious) Activated memory (Un-conscious) Focus of attention (Conscious) * * *
onebuffertoanother,�e�a��notbea�areofthe�rocessb���hichthetransfor-�ationsareacco��lishe��.Becauseofthetheoretical��ifficult��ofthisquestion, �eleaveaquestion�ar�inthecentralexecutive.Basicall��,itisnotcleartous �hetheritisfeasibletoconsi��er�rocessestobeinconsciousness,or�hetherit isonl��infor�ationinstoresthatishel��o�entoconsciousreflection.Onereso-lutionofthisquestionisthat�rocesses�a����iverisetostore��re�resentations thatarehel��inconsciousness,�hereasother�rocesseso�erate�ithoutatten-tionan��consciousness��irecte��tothe�.In��ee��,�henonebeco�estooa�are ofthecentralexecutive�rocesses��overnin��aco��lexbehavior,itcanlea��to �oor�erfor�anceor“cho�in��”(Beiloc�an��Carr2005);asF��o��orDostoevs���’s characterco��laine��intheshortnovel,Notes From Underground,insuchcases consciousnessisa��isease. Finall��,Fi��ure1Csho�stheactivation-base��,e�be����e���rocesses�o��el ofCo�an(1988,1999).Forour�ur�oses,this�o��elhasthea��vanta��ethatthe accesstoconsciousnessisa�e��as�ectofthe�o��el.Thisaccesstoconscious-nessiss��non���ous�iththefocusofattention.Ele�entsof�e�or��outsi��eof thefocusofattention,�hetheractiveornot,areoutsi��eofconsciousa�areness. Ifthelinebet�eenthefocusofattentionan��therestofactivate���e�or��is seenasablurr��or��ra��ualone,thenthefocusofattention�i��htbevie�e��as bein��thesa�eas�ri�ar���e�or��as��escribe��b��Ja�es(1890).Onereason to��e�arcateconsciousversusunconscious�rocessin��inthe�o��elisthatthe infor�ationinconsciousa�arenessisassu�e��to��ainaccessto�uch��ee�er an��extensive�erce�tualan��conce�tualanal��sisusin��lon��-ter��e�or��in-for�ationthaninfor�ationthatisoutsi��eofconsciousa�areness.Therefore, ��irectin��consciousa�arenessisani��ortants�illforharnessin��infor�ation �rocessin��tosuccee��atatas�. Oneofthestron��suitsofBa����ele��’s�o��elsisthatthe��havebeen�ell-��roun��e�� in research on �atients �ith brain injur��. One can fin�� instances in�hich�atientsa��eartobe��eficientinte��orar���honolo��icalstora��eor rehearsal (e.��., Ba����ele�� et al. 1988), attention-relate�� �or�in�� �e�or�� (e.��., Jefferiesetal.2004),orlon��-ter�e�iso��icstora��e(e.��.,Ba����ele��an��Warrin��ton 1970).Noneofthesecasesarees�eciall���roble�aticfortheCo�an�o��el,ei-ther.Itisac�no�le����e��inthe�o��elthat�honolo��icalactivationisonet���eof activate���e�or��an��thatrehearsalofitcanta�e�lace�ithout�uchattention. Attention-relate���or�in���e�or��an��auto�aticactivationarebothintrinsic totheCo�an�o��el,asislon��-ter�stora��e.Thereisnoreason�h��s�ecificle-sionscoul��notselectivel��i��airtheseas�ectsof�e�or��.Althou��h�atients �ithlon��-ter�e�iso��icstora��ei��air�entsobviousl���oul��beunabletoac-tivateinfor�ationthat�asnotstore��inthefirst�lace,infor�ationinse�antic
inshort-ter�stora��etas�s. Ani��ortantissuethat�asa����resse��inenou��h��etailb��Co�an(1988, 1999)is�hereinfor�ationaboutthein��ivi��ual’s��oalsishel��.Whenthe��oals �ee�shiftin��or�henthereisinfor�ationthatun��er�inesthe��oal,the��oal �resu�abl���ustbe�e�tinthefocusofattention,usin��u�so�eoftheli�ite�� ca�acit��ofthatstore.Anexa��leofthisistheStroo�effect,in�hichthe��oalis tona�ethecolorofin�butthe�or��s�ellsouta��ifferentcolor.Kanean��En��le (2003)sho�e��thatin��ivi��uals�ithhi��h�or�in���e�or��s�ancarr��outthis tas��oresuccessfull��thanlo�s�ansifaconflictonl��occursonas�all�ro�or-tionofthetrials.Incontrast,ifthe��oalbeco�esroutinean��itisnotun��er�ine�� b��conflictin��sti�uli,that��oalnee��notuseu�so�eoftheli�ite��ca�acit��of thefocusofattentionan���a��behel��instea��ina�ortionoflon��-ter��e�or�� (orinthecentralexecutiveitselfifitcanbeconsi��ere��tohavea�e�or��,�hich �asso�eti�esassu�e��b��Ba����ele��,butnotb��Co�an). 1.1.5 More��etailonthee�be����e��-�rocesses�o��el Thus,thee�be����e��-�rocesses�o��el,ratherthanbein��co��ose��ofse�arable structures, inclu��es �ithin the long-term memory s��ste� a currentl�� activated subsetof�e�or��an��,�ithinthatinturn,asubsetthatisthecurrentfocus of attention.Theactivate���ortionof�e�or���assai��toinclu��eunli�ite��infor- �ationatoncebutit�asassu�e��toloseitsactivationthrou��hti�e-base����e-ca���ithin10to20secon��s,�rovi��e��thatactivate��ite�sarenotatten��e��or rehearse��.Thefocusofattentionco��risesali�ite��nu�berofite�sthatare notonl��hi��hl��activate��,butarealso�ostra�i��l��accessiblean��areinone’s a�areness(‘in�in��’).Incontrasttotheti�e-li�ite����eca��ofactivate��lon��-ter��e�or��,thefocusofattention�asassu�e��notto��eca��but�asli�ite��to onl��severalse�arate,�eanin��fulite�satonce. Thefocusofattentionfunctionsasazoo�lens�ithres�ecttoitsco��risin�� infor�ation(seealsoLaBer��ean��Bro�n1989).Itcan‘zoo�in’ona�articular ite�,lea��in��to�orefocuse��an���reciseallocationofattentiontoasin��leite�, �ithre�ainin��ite�sinthefocusreceivin��consi��erabl��lessattentionan����etail; thissu����eststhatattentionalresourcescanbeallocate��onthebasisof�rioritiza- tionifnecessar��.Incontrast,if�ulti�leite�snee��tobe�rocesse��si�ultaneous-l��,thefocusofattentioncan‘zoo�out’,lea��in��toa��reaterbrea��thof�rocessin��, but�ithless�recisionoverall. Ho�infor�ationentersintoa�areness��e�en��su�onseveral��ifferentfac-torsthatareaccounte��forinthe�o��el.Thefirstfactorinvolvestheori��inof
infor�ation;ite�s�a��enterintothefocusofattentionfro�eitheraninter- nal(e.��.,infor�ationcontaine��inlon��-ter��e�or��)oranexternal(e.��.,sen-sor��infor�ationfro�theenviron�ent)source.Thee�be����e��-�rocess�o��el accounts for such ��ifferences throu��h the inclusion of t�o ��ifferent �eans to controlthefocusofattention.Attentionis��irecte��to�ar��sinternall��-��enerate�� ite�sin�e�or��viaacentralexecutive.Co�an(1999)��efine��thecentralexecu- tiveasasubsetofco��nitive�rocessesthatare�o��ifie��b��tas�-base��instruc-tions,��oals,an��incentives.Consi��erho�sucheffortfulallocationofattention �i��hto�erateina��eneralfluenc��tas�.Partici�antsare�resente���itha��iven cate��or��,suchas‘ani�als’;the��aretona�eas�an��ani�alsasthe��canfro� �e�or��.Inthiscase,thecentralexecutivecan��irectasearchof�e�or��,select- in��onl��thoseite�sthatarerelevanttothetas�(e.��.,‘ostrich’,butnot‘ostro-��oth’).Attentionis��irecte��to�ar��stheseite�s,allo�in��accesstothefocusof attention.A����itionall��,�artici�ants�ust�onitortheirres�onses,to�ee�fro� recallin��ana�e��ite��ulti�leti�es–thecentralexecutivecanfurtherselect onl��thoseani�alna�esthathavenot��etbeenrecalle��.Theset�o�rocesses�a�� bere�eate��untilnofurtherani�alna�escanberecalle��–thecentralexecutive �a��ter�inate�e�or��searchan��retrievalofcate��or��exe��lars,thusen��in�� thetas�.Contrastin��theabove��escri�tion,allocatin��attentiontoexternalsen-sor��infor�ationoccursthrou��hfilterin��throu��hthecentralexecutive(si�ilar tointernall��-��enerate��infor�ation),as�ellasthrou��horientin��tochan��esin environ�entalsti�uli.Infor�ationfro�thesensor��storesentersthecontents of�e�or��;�hetherinfor�ation��ainsaccesstothefocusofattention��e�en��s u�onite�features(as�henonelistenstoone�erson’svoice�hilei��norin��other �eo�leintheroo�). Processin���ithinthee�be����e��-�rocess�o��elalso��e�en��su�ontherela-tivefa�iliarit��ornovelt��of�resente��sti�uli.In��eneral,featuresthatre�ain fixe��overti�eorarenotnovel��onotca�tureattention,thou��hthesefeatures �a��beactivate��in�e�or��ifthe��arealrea����sufficientl��fa�iliaran��havebeen ��ee�e��tas�-relevantviathecentralexecutive.Rather,unchan��in��featuresare oftensubjecttohabituationan��lose�erce�tualsalienceoverti�e;itshoul��be note��thatforthesecases,accesstothefocusofattention�illbe�oreli�el��to occurthrou��hvoluntar��controlofattentionthrou��hthecentralexecutive.In contrast,novelor����na�icfeatures�resentintheenviron�ent��e�an��orient-in��an��allocationofattention,an��arethusinvoluntaril��ca�ture��inthefocus ofattention.
Recent research �rovi��es a����itional evi��ence for a �roce��ural, activation-base���or�in���e�or��s��ste�.Oberauer(2002,2005)�ro�osesa�o��elthat isquitesi�ilartothee�be����e��-�rocess�o��el��escribe��above.All�e�or��is containe���ithinthecontentsoflon��-ter��e�or��,asubsetof�hichisactivate��.
onei��ortantres�ect–thesizeofthefocusofattention.Whereasthee�be����e��- �rocess�o��elhasafocusofattentioncontainin��fourite�s,theOberauer�or�-in���e�or���o��el��efinesthisasaregion of direct access.Li�eCo�an’sfocus ofattention,there��ionof��irectaccesshol��sa��roxi�atel��threeorfourite�s orchun�sthatarei��e��iatel��accessiblean��availableforco��nitive�rocessin��. Unli�ethee�be����e��-�rocess�o��el,this��irect-accessre��ioncontainsana����i-tionalneste���rocess,�hichisthefocusofattention.Here,thefocusofattention hol��sonl��oneite�orchun�touseforasubsequentco��nitive�rocess. 1.1. Furthere�be����in��ofOberauer(2002) Inaseriesofex�eri�entsexa�inin��shiftsofattentionan��u���atin��inlistsof �or��sor��i��its,Oberauer(2002,2005)foun��thatthe��irectaccessre��ion�ro-�ose����e�en��soncurrentl��-relevantlists,an��thatthefocusofattentionhol��s theite�that�as�ostrecentl��u���ate��inatas�.Partici�ants�ere�resente�� �itht�olistsofeither1or3ite�s,�hich�eretobeu���ate���hena�articular ite��ascue��.Forexa��le,a�artici�ant�i��htreceiveavisuall��-�resente����i��it list:472.Oneoftheselistite�s(e.��.,thelastite�)�i��htbecue��foru���atin�� �ith–2,in��icatin��tosubtractt�ofro�thelastite�’scurrentvalue.Thus,the ne�listshoul��no�be470–this�ustberetaine��foralatertestofrecall.In a����itiontoin��icatin���hichcorres�on��in��ite��astobeu���ate��,cuesalso in��icate���hichofthet�olists�ascurrentl��relevanttothetas�.Acritical�a-ni�ulationoccurre���henanothercuein��an��subsequentu���atin��instruction �as�resente��to�artici�ants.Partici�ants�a��beas�e��tou���atea�reviousl��-u���ate��ite��ithinthetas�-relevantlist(i.e.,nos�itch)oranotherite�ina tas�-relevantlist(i.e.,anobjects�itch);finall��,the���a��beinstructe��toshift theirattentionto�ar��sthe�reviousl��-irrelevantlist,ter�e��alists�itch.Foru�-��atin��ite�s�ithinthesa�elist,res�onseti�eforobjects�itchesislon��erthan �hennoite�s�itchisrequire��.Allrelevant-listite�sarecontaine���ithinthe re��ionof��irectaccess;the��arei��e��iatel��availablefor�rocessin��.The��iffer-encesinres�onseti�esfors�itchin��ite�sversusnoite�s�itchsu����estashift ofthefocusofattentionto�ar��sthene�l��-cue��ite�;�resu�abl��,ifallite�s �ereequall��hel��,asthe��areintheCo�an�o��el,ite�s�itches�ithinanac-tivelistshoul��notresultinincrease��res�onseti�e.Ina����itiontosu��ortfora one-ite�-li�ite��focusofattention,Oberauerhasfoun��thatlist,butnotobject, s�itchesresultinincrease��res�onseti�eforu���atin��an��recalloflistite�s. Thishasbeenta�enasevi��encethats�itchin��lists�a��involve�ovin���revious-l��-relevantite�sfro�the��irect-accessre��ionintoactivate��lon��-ter��e�or��,
�ithne�l��-relevantite�sfollo�in��theo��osite�rocess.Objects�itches�ill requirelessti�eto�rocess,asalloftheite�sareinthere��ionof��irectaccess; ite�s�illsi��l��be�ove��inan��outofthefocusofattention.Finall��,Oberauer foun��thatres�onseti�eincreases�ithincreasin��listlen��th(i.e.,alist-len��th effect),butonl��forliststhat�ere�reviousl��tas�-relevant.Ass�itchin��listsre-quires�ovin��ite�sbet�eenactivate��lon��-ter��e�or��an��the��irect-access re��ion,thissu����eststhat�ovin��ite�soutofthefocusofattentionan����irect-accessre��ionis�oreeffortfulan��ti�e-��e�an��in��than�ovin��ite�sintothese neste���rocessin��re��ions.S�ecificall��,�ovin��ite�soutofthere��ionof��irect accessoccursinaserialfashion,ta�in���oreti�easlistlen��thincreases.
The results above �rovi��e stron�� evi��ence for the further e�be����e�� �ro-cessin����escribe��inOberauer’s�o��el.As�e�ill��iscussinalatersection,this �o��elfits�ell�ithcurrenttheoriesofconscious�rocessin��,�articularl��those �hereoneite�receivesconscious�rocessin��atati�e,suchasGlobalWor�s�ace Theor��(GWT)(Baarsetal.2003;Baarsan��Fran�lin2003,2007).Ho�ever,�e areoftheo�inionthat�oreex�loration�iththeabove�ara��i���isnecessar��.A �articularconcernrelatin��totheabove�ara��i���istheuseofincre��ibl��s�allset sizestotesteffectsoflistlen��than��tas�relevance.Weac�no�le����ethat�or�in�� �e�or��isli�ite��toas�allsubsetofite�s,an��thuss�allersetsarenecessar��, buttheinclusionofsetsizesisnotsufficientl��exhaustive.Forexa��le,Oberauer (2005)notesthatlistlen��thsof2an��4�ereteste��in�ilotresearch,butthetas� �astoo��ifficultfor�artici�antsun��erthesecon��itions.Forthe�ostco��re-hensiveaccountofthe��irect-accessre��ionan��focusofattention,thesesetsizes shoul��beinclu��e��inex�eri�entalcon��itions.Thisis�articularl��soforlistsof oneversust�oite�s,�hereitis�ossiblethatattention�ustchan��efro�asin-��ularfocustobein����ivi��e��inhalf.A����itionall��,setsizesthatexcee��s�an�ust alsobeconsi��ere��toenrichthis�o��elfurther.AsOberauer(2002,2005)onl�� exa�ine��subs�anlistsofite�s,itisunclearho��ovin��ite�sbet�eenthee�-be����e��co��onents�illbeaffecte��.Surel��interferencebet�eentheite�s�oul�� befar�oreli�el��,an��this�ustso�eho�beaccounte��for. Des�itethe��ifferencesbet�eenthet�o�o��els,the��arenotnecessaril��in conflict �ith re��ar��s to �rocessin�� of conscious, ��irectl��-accessible ite�s. Al- thou��hthereisnofurtherneste���rocessin��re��ions�ithinthee�be����e��-�ro-cessin���o��el,Co�an(2001)note��thatattentionisli�el��notequall����ivi��e�� bet�een the ite�s in the focus of attention, �articularl�� �hen the nu�ber of ite�s�aintaine��issubs�an(seealsoZhan��an��Luc�2008).Incases�herethe nu�berofite�sisbelo��or�in���e�or��s�an,�orethanonefixe��slotcan �rocessa��ivenite�.Thisi��liesthatso�eite�s�ithinthefocus�a��require �oreattentionalallocation,an��thus��reater�rocessin��,thanothers.Thei��ea thatli�ite��-ca�acit��attentionisallocate��toactiveite�sisnotane�one.Yantis
ofvisualsearchtas�s.Partici�ants�ereinstructe��tosearchforatar��etletter inanarra��ofa����itionalletters.Lettersinthesearcharra��either�ere�resent ina�rior,�as�e���lacehol��erarra��,�no�nasno-onsetletters,ora��eare��in locationsthat�ereblan�inthe�reviousarra��(i.e.,abru�t-onsetite�s).Fittin�� theresultin����atatothe�o��els,Yantisan��Johnsonfoun��evi��enceforatten-tional�rioritizationinvisual�e�or��.S�ecificall��,allabru�t-onsetite�s�ere �rocesse��first,��uetoauto�aticre��istration;follo�in��this,no-onsetlettersre-ceive��attention.Ite�sthatare��ee�e��hi��h�riorit���a��be�rocesse��viaeither a�ro�ose��queue�echanis�orthrou��hta��sthat��eca��overti�e,thou��hitis unclearho�theor��erof�rocessin��theseite�sisattaine��.Mostli�el��,forcases involvin��visualsearch,hi��h�riorit��ite�sareli�el���rocesse��onthebasisof si�ilarit��toatar��et(i.e.,tas�-relevantfeatures),�ithite�s�ostrese�blin��the tar��etreceivin��attentionfirst.A����itionall��,ite�sthatare�ost�erce�tuall��sa-lientare�ostli�el��toca�tureattentioninitiall��,�ithlesssalientite�sfollo�in�� suit.Withthisin�in��,thee�be����e��-�rocess�o��el�a��utilizesuch�rioritiza-tion�ithinthefocusofattention,‘zoo�in��in’ononeite�thatreceivesinitial attentionforreasonsoftas�relevanceorsalienceofitsco��risin��features.This isanalo��oustoOberauer’sone-ite�focusofattention.Weshoul��notethat�ore researchan��ex�lorationisnee��e��to��eter�inetheun��erl��in���echanis�sfor ��eter�inin���riorit��,forbothvisualan��verbalas�ectsof�or�in���e�or��.In contrasttothet�o��ifferencesthatareinitiall��assu�e��,the�o��el�ro�ose��b�� Oberaueractuall��onl����iffersinoneres�ect:Oberauer’s�o��elsi��l��contains ana����itionallevelofnestin��be��on��thatofthee�be����e��-�rocess�o��el.The �annerin�hichconscious,��irectl��-accessibleite�sare�rocesse���ithintheir res�ectivere��ionsinthet�o�o��els,ho�ever,��oesnot��iffer. To�resentinfulltheevi��enceforan��a��ainsteachofthese�o��els�oul�� betheto�icofalon��boo�ratherthanacha�ter.Belo�,�e�illsi��l���resent so�eofthebest-�no�nrelevantresearchinor��erto�rovi��eanun��erstan��in�� ofso�eofthe�otivationfortheconstructionofthee�be����e��-�rocesses�o��el, toillustratethe�otivationbehin��theassu��tionsaboutitsrelationtoconscious a�areness,an��toex�lorethecurrentstatusoftheseassu��tions.
1.2 Research basis of consciousness and embedded processes in working memory
Co�an(1988,1995,1999,2005)su��arize����iverseevi��encerelevanttothe consciousversusunconsciousstatusofinfor�ationinactivate���e�or��ver-susthefocusofattention.Whatiscriticalisthatsensor��featuresfro��ulti�le
sti�ulicanbeco�eactivate��in�e�or��atthesa�eti�e,�ithoutevi��encethat the��entera�areness.Ho�ever,��ee�er�rocessin��see�storequirea�areness, �a�in��thes��ste��oreli�ethatofBroa��bent(1958).Co�an(1988)�asnon-co��ittalabout�hethertheauto�aticall��activate��infor�ationcoul��inclu��e se�anticinfor�ation.Unli�eBroa��bent�estillassu�ethatit�a��but,li�e Broa��bent,�e��onotbelievethatauto�aticactivationofse�anticfeaturesca�-turesattention.Theevi��enceco�esfro�se�arateau��itor��an��visualstu��ies. 1.2.1 Au��itor��stu��iesrelate��toconsciousnessan���or�in���e�or�� Broa��bent(1958)su��arize���or�ofthist���eb��severalinvesti��ators.Inso�e ofthe�or�,a��ichoticlistenin���etho���asuse��in�hich��ifferent�essa��es �ere�resente��inthet�oearsusin��ata�erecor��in��.The�essa��einoneear �astobeatten��e��an��re�eate��(sha��o�e��)�hereasa��ifferent�essa��einthe otherear�astobei��nore��.Occasionall��,theta�e�assto��e��an��theresearch �artici�ant�astore�eatas�uchas�ossiblefro�theear�iththe�essa��etobe i��nore��.Onl��the�ostrecentinfor�ationfro�that�essa��ecoul��bere�e�-bere��;thelastfe�secon��satbest.Man��versionsof��ichoticlistenin��ex�eri�ent ��iel��e��infor�ationconsistent�iththeconclusionthatinfor�ationishel��ina sensor��for�an��isfor��otten�ithinafe�secon��sunlessitisentere��intoatten-tionan��consciousness. Johnstonan��Heinz(1978)�ereabletoverif��theassu��tionthatattention an��a�areness��oto��etheran��arefoun��foronechannelinselectivelistenin��. The���resente��t�oau��itor��channelsthat�ere��istin��uishe��eitherinter�sof �h��sicalcuesli�elocationan��voicequalit��,asin�ostofthestu��ies��escribe��b�� Broa��bent(1958),or�ere�resente��in�h��sicall��i��entical�eans,��ifferin��onl�� inthese�anticto�icofthe�essa��e.The�e���ani�ulation�asthat,ina����ition tosha��o�in��onechannel,�artici�antsalso�eretocarr��outathesubsi��iar�� tas�of�ressin��a�e��asquic�l��as�ossible�henavisualsi��nala��eare��.The subsi��iar��tas�reactionti�e�as�no�nfro�other�or�tobea��oo���easure ofho��uchattentionisfree��es�itetheselectivelistenin��tas�.It�asfoun��that thesubsi��iar��tas�reactionti�e�as�uchfaster�henthe�essa��es�ere�h��si- call��se�arate��than�henthe���ereonl��se�anticall��se�arate��.Withinthee�-be����e��-�rocesses�o��el,thisin��icatesthatthefocusofattentioncanbe��irecte�� atone�h��sicalstrea�ofinfor�ation�ithlittle��ifficult��.Thiscannotbe��one �henthe�essa��es��ifferonl��intheirse�antic�eanin��sbecausetheanal��sisof se�anticsisnotauto�atic;itrequiresattentionan��effort.Itsee�s�ostli�el�� thatboth�essa��esarehel��inthefocusofattentionuntilthe�ortionsrelate��toa se�anticall��coherent�essa��ecanbeextracte��.Giventhenee��tohol��so�uch
aneffortful�rocessthatleaveslittleattentiontobeuse��forthesubsi��iar��tas�. Boththee�be����e��-�rocesses�o��el(Co�an1988,1999)an��theBroa��bent (1958)�o��elareconsistent�iththesefin��in��sin��icatin��thatnot�uchauto-�aticse�antic�rocessin��contributestosha��o�in���erfor�ance.One�a��in �hichthe����ifferisinthe�annerofthecontrolofattention.Broa��bent�osits anattentionalfilteran��one�i��htthin�thatthe�orechannelstherearetobe rejecte��,thehar��erthefilter�ust�or�.InCo�an’s�o��el,incontrast,thereis nofilterin��an��thefocusofattention�ustselectonechanneltobe�rocesse�� se�anticall��,a�rocessthatnee��not��e�en��onho��an��channelsthereareto berejecte��.Afurtherex�eri�entofJohnstonan��Heinz(1978)see�stosu��ort thisa����itional�re��iction.Acon��itionin�hichthere�ereonl��t�o�h��sicall�� ��ifferent�essa��es,onetobeatten��e��an��onetobei��nore��,�asco��are��to acon��itionin�hichthere�erethree�h��sicall����ifferent�essa��es,onetobe atten��e��(afe�alevoice)an��t�otobei��nore��(t�o��ifferent�alevoices).The subsi��iar��tas�reactionti�e�asthesa�eno�atter�hetherit�asnecessar�� toi��noreoneort�ochannels,asex�ecte��accor��in��tothee�be����e���rocesses �o��elin�hichthereisnorealfilterin��outofirrelevantsti�uli,justaccentuation oftherelevantchannelor�essa��ehel��inthefocusofattention. Atoneti�ethere�asani��ortant�ove�entto�ar���o��elsin�hichinfor-�ationlea�sthrou��htheattentionalfilter,suchastheattenuatin��filter�o��elof Treis�an(1964).The�ainreasonforit�asthatthere�ereanu�berofstu��ies su����estin��thatinfor�ation��i����etthrou��h.The�ostfa�ousofthose�as�hen the�artici�ant’so�nna�e�as�resente��intheunatten��e��channelinselective listenin��(Mora��1959).Thefin��in���asthat�artici�antsso�eti�escoul��reco��-nizean��re�e�berhearin��theiro�nna�es.Woo��an��Co�an(1995a,1995b) confir�e��that�artici�antscoul��noticesubtlechan��esintheunatten��e��chan-nel,inclu��in��theiro�nna�es.It�asabout1/3ofthe�artici�ants�honotice�� theirna�es,aboutthesa�e�ro�ortionobtaine��inthes�allerstu����b��Mora��. Ho�ever,thereare��ifferent�a��sthatthiscoul��co�eabout.Itcoul��bethatin-for�ationaboutthena�ein��ee��lea�e��throu��hthefilter(or,inthee�be����e�� �rocesses�o��el,thatacousticco��onentsofthena�e�a��econtact�iththe lon��-ter��e�or��re�resentationofthena�ean��thereb��attracte��attention). Alternativel��,itcoul��bethatattentionoften�an��ere��fro�theassi��ne���essa��e overtotheunatten��e���essa��e,or�ass�litbet�een�essa��es,an��thereforethat thena�e�asalrea����atten��e���henit�ashear��.Ita��earsthatthatisthecase inas�uchasonestu����(Con�a��,Co�an,an��Buntin��2001)sho�e��that65%of in��ivi��ualsinthelo�estquartileof�or�in���e�or��notice��theirna�es,�here-asonl��20%ofin��ivi��ualsinthehi��hestquartileof�or�in���e�or��notice��their na�es.The�oststrai��htfor�ar��inter�retationisthatthehi��hs�ans�ereontas�
�oreoftenthanthelo�s�ans.Colfleshan��Con�a��(2007)sho�e��that�henthe tas��astotr��to�onitorboth�essa��esatonce,hi��h-s�anin��ivi��ualsnotice�� theirna�es�oreoftenthanlo�s�ans. 1.2.2 Visualstu��iesrelate��toconsciousnessan���or�in���e�or�� S�erlin��(1960)carrie��outase�inalstu����thatcanbeconsi��ere��thebasisof thevisual�or�relatin���or�in���e�or��toconsciousness,�uchasthe�or� revie�e��b��Broa��bent(1958)canbeconsi��ere��thebasisofthecorres�on��-in��au��itor���or�.S�erlin���resente��anarra��ofcharacters(�rinte��lettersan�� nu�bers)onaco��uterscreen,so�eti�esfollo�e��shortl��after�ar��b��atone cuein��icatin���hethertheto�,�i����le,orbotto�ro�ofcharacters�astobe re�orte��.Withnotonecue,�artici�antscoul��recallabout4ite�sfro�thearra��. Whenthetonecuefollo�e��closel��afterthearra��,the��coul��recallabout4ite�s fro�theselecte��ro�.Thisin��icate��thattherearet�oli�itsinrecall.First,there isali�itofabout4ite�sinho��uchinfor�ationcanbeextracte��into�or�-in���e�or��.Secon��,thereisali�itinho��an��ite�scanbeenco��e��fro�the arra��butitisnotnearl��assevereas4ite�s.Instea��,ita��earsthat�ostorallof thearra��ite�sareenco��e��,��iventhatthe�artici�ants��i��not�no�ina��vance �hichro��oul��becue��butstillcoul��successfull��recall4ite�sfro�thatro�. Theretentionof�ostofthearra���assai��tobeinthefor�ofsensor���e�or��, usableifattentionisturne��toitbutnotre�ortableinan��thin��nearitsentiret��. Thissensor���e�or��thereforesee�stobehel��outsi��eofthefocusofattention an��a�areness.Incontrast,thes�alla�ountof�or�in���e�or��thatisre�ort-able(about4ite�s)isinattentionan��a�areness. Luc�an��Vo��el(1997)create��acleanerversionofS�erlin��’s�roce��urethat �asinten��e��toquantif��visual�or�in���e�or��.The��use��colore��nonverbal sha�esratherthanverbalcharacterstosho�that�or�in���e�or��forevennon- verbalinfor�ationisli�ite��toabout4ite�s.Thearra��ofobjectstobere�e�-bere���asfollo�e��b��a�robethatcoul��evenbeasin��leite�,thetas�bein��to in��icate�hethertheite�chan��e��fro�thecorres�on��in��ite�intheori��inal arra��.Perfor�ance�asnearl���erfect�henthere�ere3or4ite�sinthearra��, an����ecline��asthearra��sizeincrease��.Co�an(2001)��erive��asi��lefor�ula toesti�atethenu�berofarra��ite�sin�or�in���e�or��forthesin��le-ite� �robecase,an��Rou��eretal.(2008)foun��a��oo���athe�aticalfitof��etaile�� ��atatothefor�ula. Thet���eof�e�or��observe��b��Luc�an��Vo��el(1997)isoftenconsi��ere�� tobevisual�or�in���e�or��,�hichcoul���a�eitaratherauto�aticstoreli�e thevisuos�atialbufferofAlanBa����ele��’s�o��els,�otentiall��o�eratin���ithout
to��o�iththefocusofattentionan��consciousness.More��an��Co�an(2004) sho�e��thatinterferenceoccursfro�as�o�enverbal�e�or��loa��(sevenran-��o���i��its),butnotfro�as�o�enseriesthatbloc�sarticulationbut��oesnot loa���e�or��(a�no�nseven-��i��ittele�honenu�ber).Saultsan��Co�an(2007) use����i��its�resente��in��ifferentvoicesfro�fourlou��s�ea�ersto�reventre-hearsalan��foun��thatthe�e�or��forthe��i��itstra��e��off�ith�e�or��forthe colore��visualobjects;�artici�antscoul��re�e�berabout3.5visualobjectsor, ifas�e��tore�e�berboth�o��alities,the��coul��re�e�berfe�ervisualobjects butabout3.5objectstotal,visual�lusau��itor��.Co�anan��More��(2007)sho�e�� thatthisinterferencebet�eenvisuos�atialan��au��itor��-verbalite�soccurre��in the�or�in���e�or��retention�hase,notjustintheenco��in��ofthesti�uli.It see�s,therefore,that�eare��ealin���ithacentral�or�in���e�or��storethatis li�ite��to3or4ite�sina��ults.Notsur�risin��l��,thiscentralstore�oul��bethe sa�ethatS�erlin��(1960)observe���ith�rinte��verbalcharacters.Thisli�ite��-ca�acit��store�atchestheconsciousinfor�ationthatthee�be����e��-�rocesses �o��elconceivesasthefocusofattentionan��a�areness. Stu��iesrevie�e��b��Co�an(2001)sho�e��thatin��ivi��ualsvar��quiteabit intheir�or�in���e�or��ca�acit��;a��ultsvar��fro�2to6�ith�ostin��ivi��uals intheran��eof3to5ite�s,an��chil��renan��ol��era��ults�oret���icall��about1 ite�fe�er.Thereareatleastt�o�echanis�sb���hichthevisualstorein��exe�� b��thetas�ofLuc�an��Vo��el(1997)coul��var��a�on��a��e��rou�san��in��ivi��u-als.First,itcoul��bethatso�ein��ivi��ualsare�ore��istractiblean��thereforeare lessli�el��toenco��ethecorrectinfor�ationinto�or�in���e�or��.Thiscanbe teste��b��inclu��in��so�eobjectsthataretobei��nore��(e.��.,re��bars)an��others thataretobeatten��e��(e.��.,��reenbars;atten��totheirorientations).A��istract-iblein��ivi��ual�oul��incorrectl��treatthere��barsasifthe���ererelevantan�� therefore�oul��actasiftheir�or�in���e�or���ereheavil��loa��e��.Incontrast, aless��istractiblein��ivi��ual�oul��exclu��ethere��barsan��therefore�oul��act asiftheir�or�in���e�or���asnotsoheavil��loa��e��.Vo��eletal.(2005)use��an event-relate���otential�easureof�or�in���e�or��loa��an��foun��thatin��ivi��-uals�hore�e�bere���oreite�s�ereless��istractible.McNaban��Klin��ber�� (2008) ��u�licate�� this result in an fMRI stu����, sho�in�� in��ivi��ual ��ifferences insubcorticalcentersinvolve��inexclu��in��irrelevantobjects.Ofcourse,either enco��in��ofinfor�ationintoanunconsciousstoreorenco��in��ofinfor�ation intoaconsciousstorecoul��beinfluence��b��theabilit��tofilteroutorexclu��e irrelevantite�s.Thist���eof�echanis�alsoa��rees�ell�iththenotionthat in��ivi��uals�ithbetters�anarethose�hoarebetterabletoexclu��eorinhibit irrelevantinfor�ation(Lusti��etal.2007).
Thereisotherevi��ence,thou��h,ofanother�echanis��hereb��in��ivi��uals ��ifferinca�acit��.This�echanis�isnot�ellun��erstoo��butitisa��ifferencein stora��eabilit���erse.Gol��etal.(2006)exa�ine��thisinabehavioralstu����of in��ivi��uals�ithschizo�hreniaan��health��controlsusin��arra��sofobjectstobe atten��e��an��i��nore��.The��usuall���robe��objectstobeatten��e��butoccasion-all���robe��objectstobei��nore��.Thesu�oftheatten��e��an��i��nore��ite�s in�or�in���e�or����aveanesti�ateofthetotala�ountin�or�in���e�or��, �hereasthe��ifferencebet�eenatten��e��an��i��nore��ite�s,favorin��theatten��e�� ones,��aveanesti�ateoftheefficienc��oftheattentionalfilterin���rocess.Sur�ris-in��l��,itturne��outthatthe��ifferencebet�eenthe��rou�s�asal�ostentirel��in thetotala�ountin�or�in���e�or��,�ithver��little��ifferenceinthefilterin�� efficienc��.Co�anetal.(2010)re�licate��thisfin��in��for��oun��chil��ren(7to8 ��earsol��)inco��arisontool��erchil��ren(12to13��earsol��)ora��ults,�hen thearra��sinclu��e��2relevantite�s(e.��.,circles;atten��totheircolors)an��2ir-relevantite�s(e.��.,trian��les).Ho�ever,�henthearra��sinclu��e��3relevantan�� 3irrelevantite�s,thelar��ea��e��ifferenceinca�acit��(as�easure��b��thesu�of �e�or��forrelevantan��irrelevantite�s)�asno�su��le�ente��b��as�allera��e ��ifferenceintheabilit��tofilteroutorexclu��eirrelevantite�s(as�easure��b�� the��ifferencebet�een�e�or��forrelevantversusirrelevantite�s).Thisfin��in�� su����eststhattheabilit��tofilteroutorexclu��eirrelevantite�sisco��ro�ise�� �hen�or�in���e�or��isoverloa��e��.Thatistobeex�ecte��onl��ifthe�or�in�� �e�or��storeinquestionisacentralstorethatisattention-relate��initself,asis thefocusofattentionasastora��e��evice. So�econtrovers��hasarisenre��ar��in��thenatureof�e�or��intheLuc� an��Vo��el(1997)arra��tas�base��onthe�ro�ertiesofbin��in��bet�een��ifferent featuresofobjects.Anexa��leisre�e�berin���hichsha�e�ent�ith�hich color,an��/or�hichcolor�asfoun��at�hichlocationinthearra��.Ourinitial ex�ectationafe���earsa��o�asthatintro��ucin��anattentional��istraction�oul�� ��ifferentiall�� i��air the abilit�� to re�e�ber bin��in�� infor�ation as o��ose�� tofeatureinfor�ation.Thatisbecausethefocusofattention�asvie�e��asthe vehiclefortheretentionofne�bin��in��sbet�eenfeatures(Co�an1995,1999, 2001).Theactivationofinfor�ationfro�lon��-ter��e�or��coul��notinclu��e ne�bin��in��sbet�eenfeatures,asonefin��s�henne�or�eanin��lessobjects are�resente��.Itcoul��inclu��etheinfor�ationthatana��leisre��,forexa��le, butnottheinfor�ationthatanabstractcirclethathasbeen�resente��is�ur�le. Si�ilarl��,�erce�tualtheor���o�ularinthefiel��ha��lon��hel��thatitta�esatten-tiontofor�bin��in��sbet�eenfeatures(Treis�anan��Gela��e1980).T�ostu��ies, ho�ever,sho�e��thatthis�asnotthecase.A��istractin��tas���urin��thearra�� retentiontas��asjustashar�fulforbin��in��infor�ationasit�asforthefeature infor�ation(Allenetal.2006;Co�anetal.2006).