Neural Correlates of First-Person Perspective as One ...hsinnamon.web.wesleyan.edu/wescourses/NSB-Psyc275/NeuroAnatom… · Neural Correlates of First-Person Perspective as One Constituent

Neural Correlates of First-Person Perspective as OneConstituent of Human Self-Consciousness

K Vogeley12 M May3 A Ritzl1 P Falkai4 K Zilles15and GR Fink16

Abstract

amp Taking the first-person perspective (1PP) centered upononersquos own body as opposed to the third-person perspective(3PP) which enables us to take the viewpoint of someone elseis constitutive for human self-consciousness At the underlyingrepresentational or cognitive level these operations are pro-cessed in an egocentric reference frame where locations arerepresented centered around another personrsquos (3PP) or onersquosown perspective (1PP) To study 3PP and 1PP both operating inegocentric frames a virtual scene with an avatar and red balls ina room was presented from different camera viewpoints tonormal volunteers (n = 11) in a functional magnetic resonanceimaging experiment The task for the subjects was to count theobjects as seen either from the avatarrsquos perspective (3PP) oronersquos own perspective (1PP) The scene was presented eitherfrom a ground view (GV) or an aerial view (AV) to investigatethe effect of view on perspective taking The factors perspec-tive (3PP vs 1PP) and view (GV vs AV) were arranged in a two-factorial way Reaction times were increased and percentcorrectness scores were decreased in 3PP as opposed to 1PPTo detect the neural mechanisms associated with perspective

taking functional magnetic resonance imaging was employedData were analyzed using SPMrsquo99 in each subject and non-parametric statistics on the group level Activations common to3PP and 1PP (relative to baseline) were observed in a network ofoccipital parietal and prefrontal areas Deactivations commonto 3PP and 1PP (relative to baseline) were observed predom-inantly in mesial (ie parasagittal) cortical and lateral superiortemporal areas bilaterally Differential increases of neuralactivity were found in mesial superior parietal and rightpremotor cortex during 3PP (relative to 1PP) whereas dif-ferential increases during 1PP (relative to 3PP) were found inmesial prefrontal cortex posterior cingulate cortex andsuperior temporal cortex bilaterally The data suggest that inaddition to joint neural mechanisms for example due tovisuospatial processing and decision making 3PP and 1PP relyon differential neural processes Mesial cortical areas areinvolved in decisional processes when the spatial task is solvedfrom onersquos own viewpoint whereas egocentric operations fromanother personrsquos perspective differentially draw upon corticalareas known to be involved in spatial cognition amp

INTRODUCTION

Self-consciousness includes the consciousness of onersquosown mental states such as perceptions attitudes opin-ions and intentions to act Representing and integratingsuch mental states into a common framework whichrepresents the integrity of our own mind requires theability to take a self- or first-person perspective (1PP)among other constitutive features such as experiencesof agency or transtemporal unity (Vogeley KurthenFalkai amp Maier 1999) 1PP can thus be considered asa basic constituent of a lsquolsquominimal selfrsquorsquo (Gallagher 2000)It enables us to experience the subjective multimodalexperiential space centered on our own body Thistransient relationship between oneself and objects inthe world is the key component of perceptual processes

and thus the underlying basis of every cognitive processdealing with the content of these perceptions (Vogeleyamp Fink 2003)

At a phenomenal level 1PP means the centralization ofthe subjective multidimensional and multimodal experi-ential space around onersquos own body It can be opposedto the third-person perspective (3PP) in which mentalstates are ascribed to someone else This phenomenallevel needs to be clearly distinguished from an underly-ing representational level on which different referenceframes representing the locations of entities in space canbe differentiated A reference frame can be defined as lsquolsquoameans of representing the locations of entities in spacersquorsquo(Klatzky 1998) In an egocentric reference frame con-stituted by subject-to-object relations (best described ina polar coordinate system) locations are representedrelated to a personal agent and his physical configura-tion As such an egocentric reference frame cruciallydepends on the avatarrsquos position in space and relation tothe objects present In contrast to egocentric frames so-called allocentric reference frames refer to object-

1Research Center Juelich 2University of Bonn 3University ofArmed Forces Hamburg 4Saarland University 5University ofDuesseldorf 6University of Aachen

D 2004 Massachusetts Institute of Technology Journal of Cognitive Neuroscience 165 pp 817ndash827

to-object relations that are independent from an agentrsquosposition (Aguirre amp DrsquoEsposito 1999 Klatzky 1998)

The cognitive operations when perceiving a visualscene from another personrsquos viewpoint (3PP) are likelyto differ from taking a view of the same scene from onersquosown perspective (1PP) Although the cognitive opera-tions differ phenomenally when perceiving a visualscene from another personrsquos viewpoint (3PP) or fromonersquos own perspective (1PP) both tasks are centered onthe body of the agent (other or self) To clearly separatethese two levels of descriptions the perspective-relatedterms 3PP and 1PP are used to indicate the phenomenallevel whereas the egocentric reference frame studiedhere refers to the cognitive or neural level as concep-tualized by the onlooking scientific observer The crucialdifference is that 3PP necessitates an additional translo-cation of the egocentric viewpoint from 1PP to 3PP

To date it remains unclear which neural mechanismsare associated with the ability to differentiate betweenmental processes lsquolsquobelongingrsquorsquo to either oneself or toanother person In the present functional magneticresonance imaging (fMRI) study we therefore systemat-ically varied 3PP and 1PP in a simple 3-D visuospatialtask for which visual stimuli were constructed thatshowed a virtual scene with an avatar surrounded by avariable number of red objects (Figure 1) Subjects wereasked to assess the number of red balls (ranging from 1to 3) as seen from either the avatarrsquos (3PP) or their ownperspective (1PP) To determine whether taking 3PP or1PP interacts with the camera view on the scene twoviews of the scene namely a ground view (GV) and anaerial view (AV) were presented The two factors per-spective (3PP vs 1PP) and view (GV vs AV) werearranged in a two-factorial way (Figure 1) It is importantto note that both target conditions were based onegocentric operations (on a representational or cogni-tive level) as the objects had to be located in relation toan agent in both conditions either the subject or theavatar The experiment thus focuses on the differentialactivations due to perspective taking on the phenome-

nal level of the agent Accordingly this study addressesthe issues whether (a) 3PP and 1PP rely on the same ordifferent brain regions and (b) whether the neuralmechanisms underlying 3PP and 1PP are modified bythe view onto the scene

Our study thus focuses on the egocentric or viewer-centered frame of reference Egocentric reference framescan be further subdifferentiated as they may be definedwith respect to the midline of the visual field the headthe trunk or the longitudinal axis of the limb involved inthe execution of a certain action (Behrmann 1999) Wehere refer to an egocentric reference frame with respectto the midline of the visual field as perceived fromeither 3PP or 1PP but we are unable to differentiate be-tween further subtypes of egocentric reference framesas the center of the visual field head and trunk were allin alignment to each other

RESULTS

Behavioral Data and Eye Movement Data duringfMRI Scanning

Dependent variables were the mean reaction times andthe percent correctness scores of correct answers aver-aged over all blocks for each particular condition Over-all means and standard deviations (SD) of reaction timesand percent correctness scores are given in Table 1 Forstatistical analysis of the reaction times and correctnessscores the general linear model with the factors per-spective and view as within-subject factors was used In3PP conditions subjects needed significantly more time(1095 msec SD = 1856 msec) than during 1PP con-ditions (760 msec SD = 1234 msec) F = 111157p lt 0001 There were no significant differences be-tween conditions with respect to view F = 1365p = 270 nor was there a significant interaction betweenthe two main factors F = 0002 p = 964 The numberof correct answers differed significantly with respect toboth factors perspective F = 22110 p lt 001 where

Figure 1 Two-factorial

design Two cognitive factors

perspective (3PP vs 1PP) andview (GV vs AV ) were

arranged in a two-factorial

design Typical stimulus

images with room sceneryavatar and objects are shown

Symbols (lsquolsquoBrsquorsquo) below the

depicted stimulus image

indicate the objects to becounted in the different

conditions of 1PP and 3PP

818 Journal of Cognitive Neuroscience Volume 16 Number 5

subjects made more errors during 3PP conditions andview F = 8072 p lt 001 where subjects made moreerrors during AV conditions Again no significant inter-action between the two factors was observed F = 0418p = 532

Statistical analysis of the dependent variables of gazeposition in the center of the stimulus image and of themean distance between eye fixation points (in arbitraryunits) did not reveal any significant differences betweenthe four conditions neither with respect to perspectiveor view nor the interaction thereof

Neural Correlates of Perspective Viewand Their Interaction

The main effects are summarized in Table 2andasheTable 2andashd corresponds to Figure 2AndashD Figure 2 pro-vides the pseudo-t maps provided by nonparametricstatistics on the group level as overlay images onto anormalized 3-D data set of one participant of the studyAreas with significantly increased (Figure 2A) and signif-icantly decreased neural activity (Figure 2B) associatedwith all four experimental conditions are shown inaddition to the main effect of 3PP (in contrast to 1PP)(Figure 2C) and of 1PP (in contrast to 3PP) (Figure 2D)(all images nonparametric test height thresholdp lt 05 corrected extent threshold = 10 voxels)

Activations common to all conditions (3PP-GV +3PP-AV + 1PP-GV + 1PP-AV relative to baseline) werefound in the occipito-parietal and frontal regions bilater-ally and in the left cerebellum (Table 2a Figure 2A)Deactivations common to all conditions (baseline rela-tive to 3PP-GV + 3PP-AV + 1PP-GV + 1PP-AV) werefound basically in mesial cortical structures lateral tem-poral and frontal cortex bilaterally cerebellum bilateral-ly and right postcentral cortex (Table 2b Figure 2B)

Differential neural activity during 3PP (3PP gt 1PP)was associated with increased neural activity in theprecuneus the frontal cortex bilaterally cerebellumbilaterally left temporal cortex and occipitoparietalcortex on the left side (Table 2c Figure 2C) 3PPactivations show a substantial overlap with the areasactivated by all four conditions suggesting an augmen-tation of neural activity in these areas rather than therecruitment of additional areas In contrast neuralactivity during 1PP (1PP gt 3PP) could be demonstrated

in lateral superior temporal cortex bilaterally includingthe insula mesial cortical areas (both frontal andparietal) left frontal cortex and the right postcentralgyrus (Table 2d Figure 2D) Notably 1PP associatedincreases of neural activity show a substantial overlapwith deactivations of all four conditions

These findings are illustrated by plots of the meanBOLD signal changes () (Figure 3) It can be demon-strated that the principally activated voxel (2 60 56) ofthe key contrast (3PP gt 1PP) shows a relative BOLDsignal change during 3PP that is positive compared to1PP where the opposite is true accordingly for the keycontrast (1PP gt 3PP) at its principally activated voxel(40 20 8)

With respect to the second main factor view differ-ential neural activity during GV (GV gt AV) was associ-ated with increased neural activity in the right occipitalpole (Table 2e no figure)

No area of significantly increased neural activity asso-ciated with the main effect of AV (AV gt GV) or theinteraction of perspective and view were observed

DISCUSSION

This study reveals both common and differential neuralcorrelates for perspective taking in a simple visuo-spatial task to be performed from either someone elsersquosviewpoint (3PP) or onersquos own viewpoint (1PP) Bothviewpoints require egocentric cognitive processes Inaddition to joint neural mechanisms common to both1PP and 3PP our data clearly demonstrate differentialbrain activations associated with taking 3PP as opposedto 1PP Whereas specific activations in the precuneusthe right superior parietal and right premotor cortexwere found during 3PP a differential increase of activa-tion in mesial cortical regions was observed during 1PP

During 3PP subjects are under a higher cognitivedemand as they have to translocate the egocentric pointof reference onto the avatarrsquos position Behaviorally thisleads to increased reaction times and higher error ratesThe principally activated region of the precuneus hasbeen shown in several studies to be involved in spatialcognition including spatial location as opposed to formdiscrimination (Rao Zhou Zhuo Fan amp Chen 2003)spatial location in relation to egocentric reference frame(Misaki Matsumoto amp Miyauchi 2002) and in retrieval

Table 1 Behavioral Data

3PP-GV 3PP-AV 1PP-GV 1PP-AV

Mean SD Mean SD Mean SD Mean SD

Reaction time (msec) 1102 2079 1089 1703 768 1108 752 1396

Correctness score () 900 18 873 26 994 07 973 17

This table summarizes the behavioral data of the relevant target conditions of the study Mean values and standard deviations for the targetconditions are given

Vogeley et al 819

Table 2 Neural Correlates of 3PP and 1PP

Region Cluster Size x y z t

(a) Common activations of 3PP and 1PP (3PP-GV plus 3PP-AV plus 1PP-GV plus 1PP-AV gt baseline)

Right medial occipital gyri 8103 46 76 8 1300

Left precuneus 356 12 72 52 849

Left inferior occipital gyri 560 44 80 0 803

Right inferior frontal gyrus 274 54 12 28 774

Left cerebellum 22 28 42 42 771

Left inferior parietal lobule 685 42 32 40 762

Left superior frontal gyrus 192 32 4 58 746

Left precentral gyrus 127 52 6 30 728


(b) Common deactivations of 3PP and 1PP (baseline gt 3PP-GV plus 3PP-AV plus 1PP-GV plus 1PP-AV)

Right medial temporal gyrus 11051 44 18 6 1230

Right medial frontal gyrus 202 36 38 20 940

Left medial temporal gyrus 4207 54 2 20 918


Right cerebellum 240 28 84 36 784


Right posterior cingulate gyrus 902 24 42 14 699

Left angular gyrus 116 44 72 36 625

Right insula 33 34 8 6 600


Right supramarginal gyrus 12 56 62 32 577

(c) 3PP relative to 1PP (3PP-GV plus 3PP-AV gt 1PP-GV plus 1PP-AV)

Precuneus 2303 2 60 56 1001





Left inferior frontal gyrus 57 46 8 28 609


Left medial frontal gyrus 16 30 0 52 554

Left occipital gyri 55 30 78 28 552

(d) 1PP relative to 3PP (1PP-GV plus 1PP-AV gt 3PP-GV plus 3PP-AV)

Right insula 1008 40 20 8 813

Left inferior temporal gyrus 651 60 8 16 780

Superior frontal gyrus 810 2 58 6 719

Posterior cingulate gyrus 529 0 22 40 686


of spatial information of lifelike events (Burgess Ma-guire Spiers amp OrsquoKeefe 2001 Fink et al 1996) Fur-thermore precuneus activation has been found indeductive reasoning lending support for the hypothesisthat mental models might be generated and lsquolsquoinspectedrsquorsquoduring deductive inference problems (Knauff MulackKassubek Salih amp Greenlee 2002) The additionalactivation sites in the right superior parietal cortex andright premotor cortex are known for their involvementin spatial tasks (Colby amp Goldberg 1999) including taskswith respect to action ( Jeannerod 1994) and spatialtransformation of objects (Lamm WindischbergerLeodolter Moser amp Bauer 2001) Interestingly theseregions are also activated in egocentric tasks in whichsubjects make judgments on the midsagittal position ofobjects in relation to themselves (Misaki et al 2002Galati et al 2000 Vallar et al 1999)

The partial overlap of these activations with activa-tions common to 1PP and 3PP might suggest that theseparietal regions are involved in more general processesof perspective taking From a clinical viewpoint lesionsof right posterior parietal cortex may lead to disturban-ces of visuospatial processing such as extinction or spa-tial neglect (Marshall amp Fink 2001 Behrmann 1999)Other clinical syndromes related to the right superiorparietal cortex are deficits in representing the relativelocation of objects or other persons with respect toonersquos own body also referred to as lsquolsquoegocentric disori-entationrsquorsquo (Farrell amp Robertson 2000 Aguirre amp DrsquoEspo-sito 1999) In essence patients predominantly withlesions in the posterior parietal cortex have lsquolsquodeficitsin representing the relative location of objects withrespect to the selfrsquorsquo (Aguirre amp DrsquoEsposito 1999) Le-sions as summarized by Aguirre and DrsquoEsposito (1999)comprise lesions of the superior parietal cortex eitherbilaterally or only on the right side

The parietal lobe thus appears to be a convergencezone in which spatial information is stored irrespectiveof the sensory modality of the information provided tomaintain and constantly update a multimodal body-centered representation of space (Halligan Fink Mar-shall amp Vallar 2003 Andersen Synder Bradley amp Ying1997) Accordingly activations of posterior parietal cor-tex during 3PP are likely to reflect increased demandsto the spatial reference system An interesting study inthis context was performed by Goel and Dolan (2001)presenting a three-term relational reasoning task show-ing that reasoning with concrete content recruitedpredominantly the left hemisphere whereas more ab-stract reasoning recruited right hemisphere structures(Goel amp Dolan 2001)

The main finding concerning 1PP is that of significant-ly differential task-related increases of activation during1PP as opposed to 3PP In the direct contrast between1PP as opposed to 3PP it appears that during 1PP mesialcortical and superior temporal cortical sites are recruitedif contrasted with 3PP as illustrated by the BOLD signalchange plot which demonstrates an increase in thedirect comparison of 1PP as opposed to 3PP (Figure 3)This finding does not contradict the observation that the1PP activation pattern as opposed to 3PP appears as asubset of the deactivation pattern of all four conditionscompared to the low-level baseline Note this factorialexperiment focuses on the differential neural mecha-nisms of 1PP and 3PP rather than the changes of both1PP and 3PP relative to an unspecific baseline In theliterature it has been previously shown that theseregions belong to a network of regions that in generalexhibit task-related decreases in comparison to (unspe-cific) baseline tasks (Shulman et al 1997)

More recently the concept of a lsquolsquodefault mode of brainfunctionrsquorsquo was proposed reflecting lsquolsquostates of selfrsquorsquo which

Table 2 (continued )



Left posterior cingulate gyrus 420 6 54 28 644

Anterior cingulate gyrus 104 2 34 6 640


Right postcentral gyrus 40 46 16 54 578


(e) GV relative to AV (1PP-GV plus 3PP-GV gt 1PP-AV plus 3PP-AV)

Right inferior occipital gyri 92 24 98 4 766

Summary of volume statistics under the calculations of common activations and deactivations and the main effects of 3PP 1PP and GV(nonparametric permutation test on the group level significance threshold p lt 05 corrected extent threshold 10 voxels) Data in panels andashdcorrespond to Figure 2AndashD Brodmannrsquos areas are provided according to Talairach and Tournoux (1988)

Nonparametrical permutations test on the group-level height threshold p lt 05 corrected extent threshold = 10 voxels

Vogeley et al 821

have been associated with a mesial cortical activationpattern predominantly in the anterior and posteriorcingulate and medial parietal cortex (Greicius KrasnowReiss amp Menon 2003 Gusnard Akdubak Shulman ampRaichle 2001 Raichle et al 2001) The empirical obser-vation is that the medial frontal and parietal regionstend to decrease their activity during demanding cogni-tive tasks (Raichle et al 2001) According to speculationsof Gusnard et al (2001) this might reflect a lsquolsquocontinuoussimulation of behaviorrsquorsquo or lsquolsquoan inner rehearsal as well asan optimization of cognitive and behavioral serial pro-grams for the individualrsquos futurersquorsquo in short a state of alsquolsquomultifaceted selfrsquorsquo What appears as lsquolsquostate of selfrsquorsquo onthe phenomenal level appears as lsquolsquodefault brain statersquorsquo on

the neural level The 1PP condition modeled in ourstudy could be taken as such a state of self especiallyin comparison with the 3PP condition That 3PP in ourparticular study had higher cognitive demands is re-flected by the significant increase in reaction times

In a similar vein Burgess et al (2001) argue thatmedial parietal cortex might support the lsquolsquoinspectionrsquorsquoof internal images This interpretation is also in linewith the view of Vogt Finch and Olson (1992) whodeveloped a differential concept of the anterior andposterior parts of the cingulate cortex such that theanterior part primarily subserves executive functionswhereas the posterior cortex subserves evaluativefunctions such as monitoring sensory events and the

Figure 2 Neural correlates of perspective taking Activations are projected onto a 3-D data set of one particular participant of the study

(chosen randomly from the sample) to provide a background for anatomical orientation of activation sites Aspects show the left (left column) and

right hemispheres (right column) and the medial (upper row) and lateral aspects of the brain (lower row) Activation patterns were calculatedwith a nonparametric permutation test on the group-level (height threshold p = 05 corrected extent threshold 10 voxels) (A) Activations

common to all four conditions (3PP-GV plus 3PP-AV plus 1PP-GV plus 1PP-AV relative to baseline) These widespread activations comprise

occipito-parietal regions frontal regions bilaterally and the left cerebellum ( B) Deactivations common to all four conditions (baseline relative

to 3PP-GV plus 3PP-AV plus 1PP-GV plus 1PP-AV) Regions significantly deactivated during the target conditions are mesial cortical structureslateral temporal and frontal cortex bilaterally cerebellum bilaterally and right postcentral cortex (C) Main effect of 3PP (3PP-GV plus 3PP-AV

relative to 1PP-GV plus 1PP-AV ) Taking 3PP is associated with increased activity in the precuneus the frontal cortex bilaterally cerebellum

bilaterally left temporal cortex and occipitoparietal cortex on the left side (D) Main effect of 1PP (1PP-GV plus 1PP-AV relative to 3PP-GV plus

3PP-AV) Taking 1PP is associated with increased neural activity in lateral superior temporal cortex bilaterally including the insula mesial corticalareas (both frontal and parietal) left frontal cortex and the right postcentral gyrus as opposed to 3PP conditions This pattern is a subset of the

common deactivation pattern


organismrsquos own behavior in the service of spatialorientation and memory

The view that these activations might constitute part ofthe neural basis of the core self is supported by studiessuggesting executive functions for the anterior cingulatecortex and evaluative functions for the posterior cingu-late cortex (Vogt et al 1992) As our study focuses on asimple visuospatial task the theoretical framework of theconcept of a lsquolsquocore selfrsquorsquo (Damasio 1999) as a constituentof human self-consciousness also seems to apply for self-related visuospatial processes Our data are in goodaccordance with studies on the neural correlates ofemotional experiences related to the lsquolsquocore selfrsquorsquo Self-generated emotions during recall of emotionally salientpersonal life episodes are associated with increased

activity in the anterior and posterior cingulate cortexbilaterally (Piefke Weiss Zilles Markowitsch amp Fink2003 Damasio et al 2000 Fink et al 1996) A similarresult during emotional experience is reported in a PETstudy by Critchley Mathias and Dolan (2001)

With respect to the differential activations of 1PPversus 3PP a systematic study on the shift of perspec-tives in a motor imagery task was recently performed byRuby and Decety (2001) who studied imagined mani-pulation of objects performed either by themselves orthe experimenter Neural correlates associated with 1PPwere observed in the left hemisphere only and 3PPsimulation activated right hemisphere regions onlyThese findings are consistent with our results Further-more we recently studied the effects of 1PP and 3PP in

Figure 3 Mean percent signal

changes of the key contrasts

(A) Mean percent signalchanges and their mean

standard errors (error bars) are

provided for the principally

activated voxel 2 60 56 of thekey contrast 3PP gt 1PP

(3PP-GV plus 3PP-AV relative to

1PP-GV plus 1PP-AV ) Mean

values of the raw data for thefour conditions 3PP-GV

3PP-AV 1PP-GV and 1PP-AV

were taken for this contrast atthis voxel for each participating

subject of the study The plots

show the differential increase of

3PP as opposed to 1PP All voxelcoordinates are provided

according to Talairach and

Tournoux (1988) ( B) Mean

percent signal changes andtheir mean standard errors

(error bars) are provided for

the principally activated voxel

40 20 8 of the key contrast1PP gt 3PP (1PP-GV plus 1PP-AV

relative to 3PP-GV plus 3PP-AV)

Mean values of the raw data forthe four conditions 3PP-GV


were taken for this contrast at

this voxel for each participatingsubject of the study The plots


1PP as opposed to 3PP All voxel

coordinates are providedaccording to Talairach and

Tournoux (1988)

Vogeley et al 823

an extended theory of mind task in which mental stateshad to be ascribed either to oneself or someone else Inthat study we observed an activation comprising themedial prefrontal cortex and the right temporo-parietalregion associated with 1PP (Vogeley et al 2001) Theactivation site of the medial prefrontal cortex is corrob-orated by the present study The right temporo-parietalactivation was only found in the language-based theoryof mind task during 1PP but not in the present visuo-spatial task It therefore seems plausible to assume thatthis activation site is stimulus- andor context-dependentWith respect to language tasks right hemispheric acti-vations are observed during pragmatic language tasksunder normal conditions (Bottini et al 1994 BrownellSimpson Birhle Potter amp Gardner 1990) Patientswith right hemispheric lesions demonstrate difficultieswith the understanding of metaphors indirect meaning(or indirect questions) the emotionalndashprosodic qualityof expressions and theory of mind (Happe Brownellamp Wnner 1999 Weylman Brownell Roman amp Gard-ner 1989 Bryan 1988 Brookshire amp Nicholas 1984Ross 1981)

With respect to the more general issue of spatialreference frames our study focuses on a specific typeof a spatial cognitive task performed in egocentricreference frames As summarized by Behrmann (1999)egocentric reference frames can be constituted withrespect to the midline of the visual field the head thetrunk or the longitudinal axis of the limb involved inthe execution of a certain action Our study focuses onthe aspect of translocations of different positions inspace which all involve the same type of egocentricreference frame In other words the center of the polarcoordinate system constituting an egocentric referenceframe is shifted (Vogeley amp Fink 2003) Our data showthat such a translocation involves predominantly theprecuneus region and the right superior parietal cortexon the neural level

In conclusion the results of our study reveal neuralcorrelates of 1PP as a particular constituent of humanself-consciousness Taking onersquos own perspective ap-pears to be a key component of human self-conscious-ness together with at least the experience of agency andthe experience of transtemporal unity (Vogeley et al1999) Distinct mesial cortical structures are involved ifthe perspective is 1PP This conclusion can be drawnbased on a differential activation of these regions asopposed to 3PP conditions

METHODS

Subjects

Eleven right-handed healthy male volunteers (age 25ndash32 years) with no record of neurological or psychiatricillness participated in the study Informed consent wasobtained before participation Volunteers were naıve

with respect to the experimental task as well as thepurpose of the study

Stimulus Material Tasks and Study Design

Fully controlled 3-D visual scenes were generated withthe software package 3-D Max (release 40 discreetdivision of Autodesk Montreal Canada) Virtual scenesconsisted of a quadrangular room with an avatar posi-tioned in the center of the room with red balls aroundthe avatarrsquos head at constant distances (Figure 1) Thevirtual scene showed a quadrangular room with lightgray walls and no additional visual cues like windowsdoors or furniture An avatar was positioned in thecenter of the room A variable number of red ballsranging from 1 to 3 were arranged around the avatarrsquoshead at constant distances The virtual room was illumi-nated with a central light shining onto the scene fromabove This basic scenery was used to generate thestimulus material used in this study To control forpotential confounds the following features of the scen-ery were varied systematically The number of red ballsarranged on a circle around the avatarrsquos head rangedfrom 1 to 3 the position of the avatar was varied in a waythat it either looked frontally onto a wall or into a roomcorner with a disparity of 458 the position of the camerawas rotated around the avatarrsquos position in the center ofthe room in different positions with a spacing of 608The objects were posted randomly at different positionsaround the avatarrsquos head in steps of 308 with thedistance to the head held constant Half of the renderedimages of these scenes were presented in GV with thecamera position parallel to the ground floor on the levelof the avatarrsquos head The other half was presented in AVwhich was generated by applying an elevated cameraperspective at a 608 angle to the floor A total of 384different scenes was generated Each stimulus image waspresented only once for each subject in a blocked orderStimulus images were stored and later presented as jpgfiles with a spatial resolution of 400 200 pixels

All stimulus images were presented only once persubject Stimuli were presented on a display in thecenter of a 29-cm screen on a black background for3 sec using the software program Presentation (Neuro-behavioral Systems Albany CA) Twelve stimuli werepresented per block which lasted 36 sec Subjects wereinstructed by a standardized slideshow before the ex-periment Instructions contained example stimuli thegeneral instruction to count objects from different per-spectives and the field of view (FOV) of the avatar(1508) Before each block either the instruction lsquolsquoHowmany balls does he seersquorsquo (3PP instruction) or lsquolsquoHowmany balls do you seersquorsquo (1PP instruction) were shownfor 8 sec There was no specific instruction with respectto view During the low-level baseline (rest) a blackscreen with a gray fixation cross was presented for 16 secand instructions were presented for 8 sec Per subject


eight blocks in randomized order covering the fourconditions 3PP-GV 3PP-AV 1PP-GV and 1PP-AV werepresented in four experimental runs The baseline con-dition was presented between each block of stimuli(eight blocks per run four runs) and at the beginningand at the end of each run equaling nine repetitions ofthe baseline per run The instructions for the targetconditions 1PP and 3PP were presented during thesebaseline conditions There were no particular instruc-tions for the baseline nor was there a task other than toattend and read the task instructions Subjects had toperform four runs (two blocks for each of the fourconditions) in a randomized order One hundred twen-ty-six images were acquired per run (four runs total)corresponding to nine MR scans per block at a repetitiontime (TR) of 4 sec with the first two scans of eachexperimental run but not of each block being discardedto allow for T1 saturation effects The overall duration ofthe scanning session was approximately 40 min Reac-tion times and the number of objects counted wererecorded using an fMRI-compatible response device withfour response buttons (Lightwave Medical IndustriesCST Coldswitch Technologies Richmond Canada) Allbehavioral answers were given by fingers 1ndash4 of the righthand 3PP and 1PP systematically differed in so far asduring 3PP not all objects were visible for the avatar (towhom the specific perception had to be ascribed)whereas during 1PP all objects were visible for the testperson As the number of objects in the scene wassystematically varied over all conditions to ensure com-parable stimulus material of the same complexity re-sponses were consequently necessarily unbalanced withsystematically lowered numbers of detected objectsduring 3PP as compared to 1PP To avoid differentialhemispheric activation due to unbalanced responsesduring 1PP and 3PP we let the test person respondonly with one hand throughout the experiment Cor-rectness scores and reaction times were calculated perblock and subject

Eye Movement Measurement and Analysis

All tasks were performed under free vision first becausethe answer to the question required the detection ofboth the avatarrsquos position and gaze direction the num-ber of objects and the spatial relation of the objects andthe avatarrsquos FOV and second to avoid any additionalspatial cognitive activity that could arise from a fixationtask As previously shown the factor of free versus fixedvision might influence visuospatial attention tasks (FinkDolan Halligan Marshall amp Frith 1997) To assesswhether the conditions differed by eye movementson-line monitoring of eye positions relative to thescreen on-line monitoring of eye positions relative tothe stimuli was performed using an infrared video-basedeye-tracking device (ASL 504 fitted with a long-distanceoptics module Applied Science Laboratories ASL Bed-

ford MA) Data were analyzed with respect to thenumber of gaze fixations in a rectangular region-of-interest centered upon the head of the avatar andfor the mean distance between two particular gazefixations by averaging the particular distances betweensubsequent fixation points Mean values of experimentalconditions were calculated and compared using a two-way ANOVA

Functional Magnetic Resonance Imaging

fMRI was carried out using echo planar imaging withwhole-brain coverage and a 15-T MRI system (SiemensMagnetom Vision Erlangen Germany) with the stan-dard head coil Sequences with the following para-meters were employed TR = 4000 msec echo time(TE) = 66 msec FOV = 200 200 mm2 a = 908 matrixsize = 64 64 voxel size = 3125 3125 44 mm3Using a midsagittal scout image 30 axial slices (03 mminterslice gap) were positioned to cover the whole brainScanning was performed continuously over one run andrestarted for the subsequent three runs In additionanatomical whole brain images were obtained by usinga T1-weighted 3-D gradient-echo pulse sequence (MP-RAGE magnetization-prepared rapid acquisition gradi-ent-echo) with the following parameters TR = 114 msecTE= 44 msec 158 flip angle FOV = 256 256 mm2matrix size = 200 256 128 sagittal slices with 133 mmthickness

Image Processing and Analysis

Image processing and analysis including realignmentnormalization and statistical analysis was performedusing SPMrsquo99 (Wellcome Department of Cognitive Neu-rology London UK) implemented in MATLAB (Math-works Sherborn MA) Analysis was carried out usingthe general linear model and a boxcar waveform con-volved with the hemodynamic response function Sub-ject-specific low-frequency drifts in signal changes wereremoved by a high-pass filter and global signal changeswere treated as a covariate of no interest The meanactivity of each voxel throughout the whole experimentwas used as a dependent variable Specific effects foreach voxel were tested by applying appropriate linearcontrasts to the parameter estimates for each condition(Friston et al 1995)

For group analysis a standard nonparametric mul-tiple comparisons procedure as implemented in SnPM(wwwfilionuclacukspmsnpm) was used which isbased on randomizationpermutation testing (Nicholsamp Holmes 2001) A multiple comparison procedurewas implemented by applying a single threshold test inwhich the maximum voxel statistic of the image wasconsidered Because of the large number of possiblepermutations an approximate permutation test wasused employing a subset of 1000 permutations with

Vogeley et al 825

no tradeoff in accuracy Data described and displayedare significant at a height threshold of p = 05 (cor-rected) and an extent threshold of 10 voxel throughout

To determine the increases in neural activity for agiven contrast pseudo-t tests (in the sense of nonpara-metric testing with smoothed residual variance) withappropriate contrast images for each single subject werecalculated This method was applied for determination ofactivation common to all four conditions (relative to thelow level baseline) (3PP-GV plus 3PP-AV plus 1PP-GVplus 1PP-AV relative to baseline) and deactivation com-mon to all four conditions (relative to the low levelbaseline) (baseline relative to 3PP GV plus 3PP AV plus1PP GV plus 1PP AV) as well as to determine the maineffects for which the following contrast images werecalculated for every subject relative activation during3PP (3PP-GV plus 3PP-AV relative to 1PP-GV plus 1PP-AV) relative activation during 1PP (1PP-GV plus 1PP-AV relative to 3PP-GV plus 3PP-AV) relative activationduring GV (3PP-GV plus 1PP-GV relative to 3PP-AV plus1PP-AV) and relative activation during AV (3PP-AV plus1PP-AV relative to 3PP-GV plus 1PP-GV) To determinethe main effects of the factors perspective and viewcorresponding contrast images were calculated and ana-lyzed as described above on the group level Stereotacticcoordinates of the voxels of local maximum significantactivation were determined within regions of significantrelative activity change associated with the different tasksThe anatomic localization of local maxima was assessedby reference to the standard stereotactic atlas (Talairachamp Tournoux 1988) and superposition of the respectivepseudo-t map on the mean anatomical image of allsubjects who participated in the study (which hadundergone the same anatomical stereotactic transforma-tion) Approximately corresponding Brodmannrsquos areasare provided based on Talairach and Tournoux (1988)The atlas by Talairach and Tournoux provides frequentlyused associations between Brodmannrsquos areas and stereo-tactic coordinates However it should be kept in mindthat Talairach and Tournouxrsquos version of the Brodmannmap does not reflect the complete and up-to-date cy-toarchitectonic organization of the human brain Like-wise the macroscopic landmark-based transformation ofthe schematic Brodmann map to the Talairach brain doesnot provide sufficiently precise localization of areal bor-ders in relation to landmarks of the brain surface Never-theless association of stereotactic coordinates withBrodmannrsquos areas is given in the tables for the conve-nience of readers used to this parcellation scheme Thedata were analyzed for the main effects of perspective andview and their interactions

Mean percent signal changes were taken from rawdata of every study participant for the key contrasts3PP gt 1PP (3PP-GV plus 3PP-AV relative to 1PP-GV plus1PP-AV) and 1PP gt 3PP (1PP-GV plus 1PP-AV relative to3PP-GV plus 3PP-AV) at the principally activated voxelsfor the key contrasts (Figure 3)

Acknowledgments

We thank the MR staff of the Institute of Medicine at theResearch Center Juelich for their technical support G R Fand K Z were supported by the Deutsche Forschungsgemein-schaft (DFG-KFO 112)

Reprint request should be sent to Kai Vogeley Department ofPsychiatry Sigmund-Freud-Strasse 25 53105 Bonn Germanyor via e-mail vogeleyuni-bonnde

The data reported in this experiment have been deposited inthe fMRI Data Center (httpwwwfmridcorg) The accessionnumber is 2-2004-115YN

REFERENCES

Aguirre G K amp DrsquoEsposito M D (1999) Topographicaldisorientation A synthesis and taxonomy Brain 1221613ndash1628

Andersen R A Snyder L H Bradley D C amp Ying J (1997)Multimodal representation of space in posterior parietalcortex and its use in planning movements Annual Reviewsin Neuroscience 20 303ndash330

Behrmann M (1999) Spatial reference frames and hemispatialneglect In M Gazzaniga (Ed) The new cognitiveneurosciences (pp 651ndash666) Cambridge MIT Press

Bottini G Corcoran R Sterzi R Paulesu E Schenone PScarpa P Frackowiak R S amp Frith C D (1994) Therole of the right hemisphere in the interpretation offigurative aspects of language Brain 117 1241ndash1253

Brookshire R H amp Nicholas C E (1984) Comprehension ofdirectly and indirectly stated main ideas and details indiscourse by brain-damaged and non-brain-damagedlisteners Brain and Language 21 21ndash36

Brownell H H Simpson T L Bihrle A M Potter H H ampGardner H (1990) Appreciations of metaphoricalalternative word meanings by left and right brain-damagedpatients Neuropsychologia 28 375ndash383

Bryan K L (1988) Assessment of language disorders afterright hemisphere damage British Journal of Disorders ofCommunication 23 111ndash125

Burgess N Maguire E A Spiers H J amp OrsquoKeefe J (2001)A temporoparietal and prefrontal network for retrievingthe spatial context of lifelike events Neuroimage 14439ndash453

Colby C L amp Goldberg M E (1999) Space and attention inparietal cortex Annual Reviews in Neuroscience 22319ndash349

Critchley H D Mathias C J amp Dolan R J (2001)Neuroanatomical basis for first- and second-orderrepresentations of bodily states Nature Neuroscience 4207ndash212

Damasio A R (1999) The feeling of what happens Body andemotion in the making of consciousness New YorkHarcourt Brace

Damasio A R Grabowski T J Bechara A Damasio HPonto L L Parvizi J amp Hichwa R D (2000) Subcorticaland cortical brain activity during the feeling of self-generatedemotions Nature Neuroscience 3 1049ndash1056

Farrell M J amp Robertson I H (2000) The automaticupdating of egocentric spatial relationships and itsimpairment due to right posterior cortical lesionsNeuropsychologia 38 585ndash595

Fink G R Dolan R J Halligan P W Marshall J C amp FrithC D (1997) Space-based and object-based visual attentionShared and specific neural domains Brain 120 2013ndash2028

Fink G R Markowitsch H J Reinkemeier M Bruckbauer


T Kessler J amp Heiss W D (1996) Cerebral presentationof onersquos own past Neural networks involved inautobiographical memory Journal of Neuroscience 164275ndash4282

Friston K J Homes A P Worsley K J Poline J -P Frith CD amp Frackowiak R S J (1995) Statistical parametric mapsin functional imaging A general linear approach HumanBrain Mapping 2 189ndash210

Galati G Lobel E Vallar G Berthoz A Pizzamiglio L amp LeBihan D (2000) The neural basis of egocentric andallocentric coding of space in humans A functionalmagnetic resonance study Experimental Brain Research133 156ndash164

Gallagher I (2000) Philosophical conceptions of the selfImplications for cognitive science Trends in CognitiveSciences 4 14ndash21

Goel V amp Dolan R J (2001) Functional neuroanatomy ofthree-term relational reasoning Neuropsychologia 39901ndash909

Greicius M D Krasnow B Reiss A L amp Menon V (2003)Functional connectivity in the resting brain A networkanalysis of the default mode hypothesis Proceedings of theNational Academy Sciences USA 7 253ndash258

Gusnard D A Akbudak E Shulman G L amp Raichle M E(2001) Medial prefrontal cortex and self-referential mentalactivity Relation to a default mode of brain functionProceedings of the National Academy of Sciences USA 984259ndash4264

Halligan P W Fink G R Marshall J C amp Vallar G (2003)Spatial cognition Evidence from visual neglect Trends inCognitive Science 7 125ndash133

Happe F G E Brownell H amp Winner E (1999) Acquiredlsquolsquotheory of mindrsquorsquo impairments following stroke Cognition70 211ndash240

Jeannerod M (1994) The representing brain Neuralcorrelates of motor intention and imagery Behavioraland Brain Sciences 17 187ndash245

Klatzky R L (1998) Allocentric and egocentric spatialrepresentations Definitions distinctions andinterconnections In C Freksa amp C Habel (Eds)Spatial cognition An interdisciplinary approach torepresenting and processing spatial knowledge (pp 1ndash17)Heidelberg Springer-Verlag

Knauff M Mulack T Kassubek J Salih H R amp GreenleeM W (2002) Spatial imagery in deductive reasoning Afunctional MRI study Cognitive Brain Research 13 203ndash212

Lamm C Windischberger C Leodolter U Moser E ampBauer H (2001) Evidence for premotor cortex activityduring dynamic visuospatial imagery from single-trialfunctional magnetic resonance imaging and event-relatedslow cortical potentials Neuroimage 14 268ndash283

Marshall J C amp Fink G R (2001) Spatial cognition Wherewe were and where we are Neuroimage 14 S2ndashS7

Misaki M Matsumoto E amp Miyauchi S (2002) Dorsal visual

cortex activity elicited by posture change in a visuo-tactilematching task NeuroReport 13 1797ndash1800

Nichols T E amp Holmes A P (2001) Nonparametricpermutation tests for functional neuroimaging A primerwith examples Human Brain Mapping 15 1ndash25

Piefke M Weiss P H Zilles K Markowitsch H J amp FinkG R (2003) Differential remoteness and emotional tonemodulate the neural correlates of autobiographical memoryBrain 126 650ndash668

Raichle M E MacLeod A M Snyder A Z Powers W JGusnard D A amp Shulman G L (2001) A default mode ofbrain function Proceedings of the National Academy ofSciences USA 98 676ndash682

Rao H Zhou T Zhuo Y Fan S amp Chen L (2003)Spatiotemporal activation of the two visual pathways in formdiscrimination and spatial location A brain mapping studyHuman Brain Mapping 18 79ndash89

Ross E D (1981) The aprosodias Functionalndashanatomicorganization of the affective components of languagein the right hemisphere Archives of Neurology 38561ndash569

Ruby P amp Decety J (2001) Effect of subjective perspectivetaking during simulation of action A PET investigation ofagency Nature Neuroscience 4 546ndash550

Shulman G L Fiez J A Corbetta M Buckner R L MiezinF M Raichle M E amp Petersen S E (1997) Commonblood flow changes across visual tasks II Decreases incerebral cortex Journal of Cognitive Neuroscience 9648ndash663

Talairach J amp Tournoux P (1988) Coplanar stereotacticatlas of the human brain Stuttgart Thieme

Vallar G Lobel E Galati G Berthoz A Pizzamiglio L ampLe Bihan D (1999) A fronto-parietal system for computingthe egocentric spatial frame of reference in humansExperimental Brain Research 124 281ndash286

Vogeley K Bussfeld P Newen A Herrmann S Happe FFalkai P Maier W Shah N J amp Fink G R (2001) Mindreading Neural mechanisms of theory of mind andself-perspective Neuroimage 14 170ndash181

Vogeley K amp Fink G R (2003) Neural correlates offirst-person-perspective Trends in Cognitive Science 738ndash42

Vogeley K Kurthen M Falkai P amp Maier W (1999) Theprefrontal cortex generates the basic constituents of theself Consciousness and Cognition 8 343ndash363

Vogt B A Finch D M amp Olson C R (1992) Functionalheterogeneity in cingulate cortex The anterior executiveand posterior evaluative regions Cerebral Cortex 2435ndash443

Weylman S T Brownell H H Roman M amp Gardner H(1989) Appreciation of indirect requests by left- andright-brain-damaged patients The effects of verbal contextand conventionality of wording Brain and Language 36580ndash591

Vogeley et al 827

to-object relations that are independent from an agentrsquosposition (Aguirre amp DrsquoEsposito 1999 Klatzky 1998)

The cognitive operations when perceiving a visualscene from another personrsquos viewpoint (3PP) are likelyto differ from taking a view of the same scene from onersquosown perspective (1PP) Although the cognitive opera-tions differ phenomenally when perceiving a visualscene from another personrsquos viewpoint (3PP) or fromonersquos own perspective (1PP) both tasks are centered onthe body of the agent (other or self) To clearly separatethese two levels of descriptions the perspective-relatedterms 3PP and 1PP are used to indicate the phenomenallevel whereas the egocentric reference frame studiedhere refers to the cognitive or neural level as concep-tualized by the onlooking scientific observer The crucialdifference is that 3PP necessitates an additional translo-cation of the egocentric viewpoint from 1PP to 3PP

To date it remains unclear which neural mechanismsare associated with the ability to differentiate betweenmental processes lsquolsquobelongingrsquorsquo to either oneself or toanother person In the present functional magneticresonance imaging (fMRI) study we therefore systemat-ically varied 3PP and 1PP in a simple 3-D visuospatialtask for which visual stimuli were constructed thatshowed a virtual scene with an avatar surrounded by avariable number of red objects (Figure 1) Subjects wereasked to assess the number of red balls (ranging from 1to 3) as seen from either the avatarrsquos (3PP) or their ownperspective (1PP) To determine whether taking 3PP or1PP interacts with the camera view on the scene twoviews of the scene namely a ground view (GV) and anaerial view (AV) were presented The two factors per-spective (3PP vs 1PP) and view (GV vs AV) werearranged in a two-factorial way (Figure 1) It is importantto note that both target conditions were based onegocentric operations (on a representational or cogni-tive level) as the objects had to be located in relation toan agent in both conditions either the subject or theavatar The experiment thus focuses on the differentialactivations due to perspective taking on the phenome-

nal level of the agent Accordingly this study addressesthe issues whether (a) 3PP and 1PP rely on the same ordifferent brain regions and (b) whether the neuralmechanisms underlying 3PP and 1PP are modified bythe view onto the scene

Our study thus focuses on the egocentric or viewer-centered frame of reference Egocentric reference framescan be further subdifferentiated as they may be definedwith respect to the midline of the visual field the headthe trunk or the longitudinal axis of the limb involved inthe execution of a certain action (Behrmann 1999) Wehere refer to an egocentric reference frame with respectto the midline of the visual field as perceived fromeither 3PP or 1PP but we are unable to differentiate be-tween further subtypes of egocentric reference framesas the center of the visual field head and trunk were allin alignment to each other

RESULTS

Behavioral Data and Eye Movement Data duringfMRI Scanning

Dependent variables were the mean reaction times andthe percent correctness scores of correct answers aver-aged over all blocks for each particular condition Over-all means and standard deviations (SD) of reaction timesand percent correctness scores are given in Table 1 Forstatistical analysis of the reaction times and correctnessscores the general linear model with the factors per-spective and view as within-subject factors was used In3PP conditions subjects needed significantly more time(1095 msec SD = 1856 msec) than during 1PP con-ditions (760 msec SD = 1234 msec) F = 111157p lt 0001 There were no significant differences be-tween conditions with respect to view F = 1365p = 270 nor was there a significant interaction betweenthe two main factors F = 0002 p = 964 The numberof correct answers differed significantly with respect toboth factors perspective F = 22110 p lt 001 where

Figure 1 Two-factorial

design Two cognitive factors

perspective (3PP vs 1PP) andview (GV vs AV ) were

arranged in a two-factorial

design Typical stimulus

images with room sceneryavatar and objects are shown

Symbols (lsquolsquoBrsquorsquo) below the

depicted stimulus image

indicate the objects to becounted in the different

conditions of 1PP and 3PP












DISCUSSION









Vogeley et al 819


























Precuneus 2303 2 60 56 1001










Right insula 1008 40 20 8 813






















Vogeley et al 821















































Tournoux (1988)

Vogeley et al 823




METHODS

Subjects
















Vogeley et al 825




Acknowledgments




REFERENCES















































Vogeley et al 827











DISCUSSION









Vogeley et al 819


























Precuneus 2303 2 60 56 1001










Right insula 1008 40 20 8 813






















Vogeley et al 821















































Tournoux (1988)

Vogeley et al 823




METHODS

Subjects
















Vogeley et al 825




Acknowledgments




REFERENCES















































Vogeley et al 827


























Precuneus 2303 2 60 56 1001










Right insula 1008 40 20 8 813






















Vogeley et al 821















































Tournoux (1988)

Vogeley et al 823




METHODS

Subjects
















Vogeley et al 825




Acknowledgments




REFERENCES















































Vogeley et al 827


















Vogeley et al 821















































Tournoux (1988)

Vogeley et al 823




METHODS

Subjects
















Vogeley et al 825




Acknowledgments




REFERENCES















































Vogeley et al 827















































Tournoux (1988)

Vogeley et al 823




METHODS

Subjects
















Vogeley et al 825




Acknowledgments




REFERENCES















































Vogeley et al 827

































Tournoux (1988)

Vogeley et al 823




METHODS

Subjects
















Vogeley et al 825




Acknowledgments




REFERENCES















































Vogeley et al 827




METHODS

Subjects
















Vogeley et al 825




Acknowledgments




REFERENCES















































Vogeley et al 827










Vogeley et al 825




Acknowledgments




REFERENCES















































Vogeley et al 827




Acknowledgments




REFERENCES















































Vogeley et al 827































Vogeley et al 827

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Neural Correlates of First-Person Perspective as One ...hsinnamon.web.wesleyan.edu/wescourses/NSB-Psyc275/NeuroAnatom… · Neural Correlates of First-Person Perspective as One Constituent