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Summary: Behavioral/Systems/Cognitive
Dorsolateral Prefrontal Cortex Drives Mesolimbic
Dopaminergic Regions to Initiate Motivated Behavior
Ian C. Ballard,1* Vishnu P. Murty,1,2* R. McKell Carter,1,2 Jeffrey J. MacInnes,1,3 Scott A. Huettel,1,3
and R. Alison Adcock1,4
1Center for Cognitive Neuroscience, and Departments of 2Neurobiology, 3Psychology and Neuroscience, and 4Psychiatry, Duke University, Durham, North
Carolina 27708
Howdoesthebraintranslateinformationsignalingpotentialrewardsintomotivationtogetthem?Motivationtoobtainrewardisthought
todependonthemidbrain[particularlytheventraltegmentalarea(VTA)],thenucleusaccumbens(NAcc),andthedorsolateralprefron-
talcortex(dlPFC),butitisnotclearhowtheinteractionsamongtheseregionsrelatetoreward-motivatedbehavior.Tostudytheinfluence
of motivation on these reward-responsive regions and on their interactions, we used dynamic causal modeling to analyze functional
magneticresonanceimaging(fMRI)datafromhumansperformingasimpletaskdesignedtoisolaterewardanticipation.TheuseoffMRI
permitted the simultaneous measurement of multiple brain regions while human participants anticipated and prepared for opportuni-
tiestoobtainreward,thusallowingcharacterizationofhowinformationaboutrewardchangesphysiologyunderlyingmotivationaldrive.
Furthermore,wemodeledtheimpactofexternalrewardcuesoncausalrelationshipswithinthisnetwork,thuselaboratingalinkbetween
physiology,connectivity,andmotivation.Specifically,ourresultsindicatedthatdlPFCwastheexclusiveentrypointofinformationabout
rewardinthisnetwork,andthatanticipatedrewardavailabilitycausedVTAactivationonlyviaitseffectonthedlPFC.Anticipatedreward
thusincreaseddlPFCactivationdirectly,whereasitinfluencedVTAandNAcconlyindirectly,byenhancingintrinsicallyweakorinactive
pathwaysfromthedlPFC.Ourfindingsofadirectionalprefrontalinfluenceondopaminergicregionsduringrewardanticipationsuggest
a model in which the dlPFC integrates and transmits representations of reward to the mesolimbic and mesocortical dopamine systems,
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