2 betweenthetheoriesisthatGNWT
def i nes consciousness a s a message,
whereasITTdefinesit asa specialkind
of structure,”explainsProfGiulioTononi,
a neu roscient ist at t heUn iversit y of
Wisconsinandoneof thefoundersof ITT.
Thefirstexperimentis ledbyProfLucia
MelloniattheMaxPlanckInstitutefor
EmpiricalAesthetics,andfollowingthe
principlesofopenscience,isentirely
preregistered (t hismea nst hat allt he
methodsandhypothesesaredeclaredin
advanceandmadepublic).Duetorun
forthreeorfouryears,theexperiment
w il l i nvolve volu nteers look i ng at
varioustask-relevantandtask-irrelevant
stimuliandplayingvideogameswhile
t hei r bra i n ac t iv it y is recorded by
multiplemethods,includingmagneto-
elec t roencepha log raphy, f u nc t iona l
magneticresonanceimagingandinvasive
intracortical recordings. It’s hoped thepatternsof neuralactivityrecordedindifferentstatesof conscious
awarenesswillprovidedecisiveevidenceinfavourof ITTorthe
GNWT– asagreedbytheleadersof thosetheories.Forinstance,
GNWTpredictsconsciousnesswillbecorrelatedwithactivity
inthefrontalandparietalregionsofthebrainasinformation
isbroadcasttospecialistmodules,whereasITTpredictsthe
backofthebrainwillbemorerelevanttoconsciousnesssince
it hasthenecessarystructuralproperties.
“I amoptimisticthatIITwillnotfaretoobadly,”saysTononi.
“ButI alsohopetolearnsomethingnoneofusexpected,which
isoftena wonderfulbonusofscience.”
Inthefurtheryet-to-be-agreedexperiments,othertheories
tobetestedincludeso-calledhigher-ordertheories,predictive
coding theories and quantum theories (see box, previous page).MIXEDREVIEWS
Noteveryoneis completelyenthusiasticaboutthenewinitiative.
TakeDrKeithFrankish,a philosopherattheUniversityof
Sheffield,whoisscepticalaboutanytheoriesthatclaimto
explainoursubjectiveor‘phenomenal’senseofconsciousness
(the‘whatit feelslike’aspect)intermsofbrainprocesses.
“Themostwecanhopetodois tofindcorrelationsbetween
brainprocessesandphenomenalproperties,”hesays.“And
eventhenthere’sa methodologicalproblem.For therecan
benoobjectivetestforthepresenceofessentiallysubjective
properties.”Thatis,byitsverynature,thefirst-personaspect
ofconsciousnesscanonlybereportedanddescribedbythe
personhavingtheexperience(whichiswhyyouandI can
neverknowif ourfirst-personexperienceof,say,thecolourred
isthesame– a dilemmathatrelatestowhatChalmerscalled
the‘hardproblem’).
Frankishbelievesourphenomenalfirst-personsense of
consciousnessis essentiallyanillusioncreatedbythebrain– an
approachhecalls‘illusionism’.“Thefundingforexperimental
workis welcomeandthedatagatheredwillbeuseful,”hesays.
“Buttheprojectisunlikelytosettleanythinguntilwehavea
betterconceptionof exactlywhatit is wearetryingtoexplain.”
Fra n k ish is a fa n of D r M ic hael Gra zia no’sAt tent ion
Schema Theor y, wh ich sees consciousness as t he bra in’sFEATURE CONSCIOUSNESS