MANIPULATING ATTENTION IN COMPUTER GAMES. M. Bernhard, L. Zhang, M. Wimmer

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1 MANIPULATING ATTENTION IN COMPUTER GAMES M. Bernhard, L. Zhang, M. Wimmer Vienna University f Technlgy Institute f Cmputer Graphics and Algrithms Favritenstr. 9-11, Vienna, Austria ABSTRACT In cmputer games, a user s attentin is fcused n the current task, and task-irrelevant details remain unnticed. This behavir, knwn as inattentinal blindness, is a main prblem fr the ptimal placement f infrmatin r advertisements. We prpse a guiding principle based n Wlfe s thery f Guided Search, which predicts the saliency f bjects during a visual search task. Assuming that cmputer games elicit visual search tasks frequently, we applied this mdel in a reverse directin: Given a target item (e.g., advertisement) which shuld be nticed by the user, we chse a frequently searched game item and mdify it s that it shares sme perceptual features (e.g., clr r rientatin) with the target item. A memry experiment with 36 participants shwed that in an actin vide game, advertisements were mre nticeable t users when this methd is applied. Index Terms saliency, in-game advertising, inattentinal blindness, guided search, attentin guidance 1. INTRODUCTION In-game advertising has becme an attractive channel fr marketing since cmputer games have emerged as ne f the strngest sectrs within the entertainment industry, reaching particularly yung custmer grups. On the ther hand, the cmputer game industry benefits frm advertising as a new revenue stream. The big difference t mst ther entertainment media, e.g., televisin, is that the user interacts with the cmputer game, resulting in a highly cncentrated, fcused, and emtinally fascinating perceptin f the displayed cntent. Hwever, the interactive nature f cmputer games cmes with a severe limitatin f the effectiveness f traditinal passive frms f advertising, such as prduct placement n billbards [1]. As cmputer games frequently require the player t efficiently prcess many items simultaneusly, selective attentin creates a perceptual bttleneck where almst exclusively the task-relevant infrmatin may pass thrugh. This wrk was funded by the FWF-General Purpse Visibility P prject The amunt f attentinal resurces left t prcess taskirrelevant infrmatin, such as advertisements, decreases with increasing difficulty f the task [2]. Since cmputer games usually impse an intensive task, players are blind fr all elements in the game envirnment which d nt cntribute taskrelevant infrmatin r which are nt expected by the user t be related t the task. This effect, named inattentinal blindness [3], was demnstrated t be impressively strng, and even cnspicuus bjects r bjects in the fveal field f view may remain unnticed. In this paper, we investigate a methd t manipulate attentin particularly in situatins where the task ccupies many attentinal resurces. Attentin is manipulated by changing the visual design in a way that takes int accunt the current task and the resulting attentinal behavir. The main idea is t increase the saliency f advertising billbards n a cgnitive level. This is achieved by designing task-relevant bjects that are frequently searched by the user with clrs and ther principal perceptual features (e.g. rientatin) that are cmmn with the advertising billbards. We establish this methd n the theretical basis f Wlfe s Guided Search [4], a thery explaining tp-dwn guidance in pre-attentive visin and visual search, and present a perceptual study validating the effectiveness. 2. RELATED WORK Directing attentin in Virtual Envirnments (VEs): Thugh there is a grwing academic field cncerned with measuring, mdeling and predicting visual attentin in VEs, there are, t ur best knwledge, rather few prpsals which attempt t take active cntrl n attentin. One apprach was prpsed by El-Nasr et al. [5], wh designed a system which attempts t guide a user s attentin in a VE by autmatically adjusting lighting cnditins, including angles, psitins, intensities, and clrs f the light surces. A methd that perates n the prperties f preattentive visin was prpsed by Bailey et al. [6]. They used shrt luminance r warmcl mdulatins f peripheral image-space regins t direct a user s gaze, which is very sensitive and attracted t sudden changes in the periphery f the fvea. T avid cnscius

2 perceptin f theses mdulatins, an eye tracker ntifies the system when a saccade t the mdulated regins is triggered, upn which the mdulatins have t be stpped. Thugh this methd is very prmising fr future custmer hardware, the requirement f an eye tracker is a severe limitatin fr many ptential applicatins. Advertising and infrmatin placement in VEs: In-game advertising has emerged as a research area just very recently, and little is knwn yet abut its effectiveness. Research questins which have been addressed mainly cncern acceptance, cngruity with the schematic cntext, interactive advertising, effects n players attitude twards advertised brands, and suitability f game genres fr advertising. Hwever, apart frm marketing surveys, there are few studies cncerned with the perceptin f advertisements in VEs and games. One factr related t visual attentin is schematic cngruency f advertisements. Lewis et al. [7] fund that advertisements that are schematically incngruent are mre cnspicuus and hence better remembered. But n the ther hand, incngruity may decrease realism significantly (e.g., a sft-drink advertisement in a histrical envirnment). Anther factr fr the visibility f advertisements is placement. Therefre, Dixit et al. [8] prpsed a tl t evaluate the bservatin densities fr surfaces in VEs frm recrded viewpint traces. But the crrelatin between bservatin densities and recall f advertisements was rather lw. Pr perfrmance in remembering embedded advertisements was als reprted by Melzer et al. [9], wh cnducted a study with a car racing game t evaluate the effect f vilence in games n brand memry, and Chaney et al. [1], wh carried ut a study with a first-persn shter. Our intuitin is that embedded advertisements are perceived as parts f the backgrund, which serves as decratin rather than being relevant fr the game tasks. Unless they are bviusly schematically incngruent r smehw linked with the task, embedded advertisements will remain unnticed due t the player s inattentinal blindness. 3. BREAKING TROUGH INATTENTIONAL BLINDNESS We hypthesize that we can break thrugh inattentinal blindness by increasing the saliency f specified bjects with respect t tp-dwn factrs invlved during task executin. Thugh it is rather difficult t mdel tp-dwn cntrl fr general behavir, there are relatively well examined mdels fr tp-dwn cntrl during a visual search task. Expliting the fact that in mst cmputer games, visual search tasks are perfrmed frequently (e.g., searching fr a health item), we apply an established mdel in a reverse fashin by designing the game in a way that it predicts a high saliency fr bjects we intend t receive sme attentin. Guided Search: Accrding t Treisman and Gelade s Thery f Feature Integratin [10], visual search invlves tw stages: a parallel preselectin and a serial search in preselected regins. The first is dented as preattentive visin and encdes the visual scene alng a number f separable dimensins (e.g. clr r rientatin) prcessed in several feature maps. Due t parallel prcessing, preattentive search is very efficient, but fails t cmbine features f different channels. Since in many cases, several features have t be cmbined t distinguish a target frm distractrs, selective attentin is required fr feature integratin t be carried ut serially at the secnd stage. Overall, preattentive visin ptimizes serial search by increasing the saliency f regins bearing imprtant features in rder t guide selective attentin (e.g. eye mvements) twards them. Since the riginal thery des nt explain hw tp-dwn cntrl affects search fr a particular target, Wlfe prpsed Guided Search [4] as an imprtant extensin. His mdel suggests that tp-dwn guidance ccurs thrugh a selective manipulatin f the impact f particular feature maps. Therefre it is assumed that the visual system hlds a representatin f a search target where the characteristic features fr feature-based search are available. Fr example, if a yellw line with a leftward slpe is the search target, then the feature maps fr the yellw channel and the rientatin f -45 degrees are weighted higher. Finally the weighted feature maps are cmbined int ne tpgraphical master activatin map, and serial search is guided frm ne psitin crrespnding t peaks f activatin t the next until a target is fund. Perceptually adjusted game design: The main idea prpsed in this paper is t direct attentin intentinally t particular bjects by designing the game in a way that thse elements becme distractrs in a visual search task. Accrding t the Guided Search mdel, we prvke the elements that shuld be nticed t becme false psitives f serial search since they cause peaks in the master activatin map. Nw the basic idea is t select an imprtant visual search task and design the crrespnding search target in a way that it shares sme features with an additinal backgrund element that is intended t be recgnized. Thus, during the search, the user will find bth, the target and the backgrund element. T this end, we prpse the fllwing three requirements t cnstruct an apprpriate visual search task: first, the task is perfrmed frequently; secnd, the psitin where the target may appear is unpredictable; and third, the target bject is linked with psitive assciatins.the first requirement was set t assure that the targeted backgrund item is attended regularly in rder t btain a strng effect. The secnd prperty shuld avid targets t be fund with strategies ther than feature-based search, which may ccur when a player can learn cntextual and spatial cnstraints fr a target s lcatin. The third requirement addresses the emtinal impact f ur methd, due t the fact that advertising is the studied target applicatin. Hwever, the reasns fr these chices were

3 avatar missile enemy missile health item 1 ( TEST & CTRL 1 ) health item 2 ( CTRL 2) avatar bt enemy bt flying mine Fig. 1. Elements f the game. based n intuitin, and future studies wuld be necessary t justify thse decisins scientifically. 4. USER STUDY T validate ur hypthesis, we created an actin vide game that cntains advertisements f famus brands in the backgrund scene. A memry test was used t measure the effects n users attentin. Cmpared t eye tracking, this is a mre cnservative way t bserve what has actually been attended, since a user may ften lk withut seeing [11]. We decided t use real brands with high visibility (in the gegraphical regin the study tk place) fr several reasns: Lgs f real and ppular brands are a result f a sphisticated design prcess. They are ptimized t be aesthetically pleasant, well recgnized and remembered easily. We hence believe that using hme-grwn fictinal creatins wuld prvide a less realistic applicatin scenari. Hwever, a reasnable cncern that can be raised is that using real brands intrduces a ptential bias due t differences in ppularity and saliency f particular designs. Therefre we cntrlled ptential bias in tw ways: n the ne hand, we used brands f similar ppularity (in the regin the study tk place) accrding t the BrandZ Ranking Reprt 2010 [12]. On the ther hand, remaining differences are cmpensated since all interpretatins f ur results (i.e., statistical tests) are based n cmparisns with cntrl cnditins where the same advertisements were used and which hence wuld have been influenced by the same latent factrs The Game We authred a representative 2D actin game with a typical game task f ppular casual actin games and a 3D backgrund where the advertisements were embedded. The game runs in a display windw f a reslutin f 1, pixels and is cmpsed f the fllwing elements (Figure 1): The avatar (size: 56x76 pixels) is a grey rbt shting bullets in vertical directin, which can mve in all directins (in 2D). Fig. 2. Screensht f the actin game (TEST cnditin) Enemies (size: 60x83) are green rbts mving frm left t right n a randm path, sht in vertical directin and are killed by ne bullet, resulting in an explsin and a gain f 10 game pints. A hit by an enemy bullet csts 15 health pints. Flying mines (size: 41x39) have a greyish clr, fly n a randm path frm left t right and cause a reductin f 20 health pints when the avatar cllides with them. Health items (size: 80x53) are static, spawned n randm psitins and cllected by mving ver with the avatar (+ 20 health pints, + 80 game pints) A player starts the game with three lives, each crrespnding t 60 health pints. The task is t avid lsing all health pints (which results in a Game Over ) while trying t gather as many game pints as pssible. During the game, the frequency f spawning enemies and mines increases cnstantly. This has the effect that with survival time, difficulty increases, while game pints can be earned faster due t an increased frequency f ptentially annihilated enemies Advertisement Placement and 3D Backgrund Scene The backgrund was created using 3D Studi Max. It cntains a mdern city scene with sky scrapers in frnt f a mrning sky. This backgrund is well suited t embed advertisements in a schematically cngruent cntext. Advertisement were placed n six billbards with predefined psitins. A screensht f the game is shwn in Figure 2. Fr the sake f neutrality, we blurred the adverts fr this presentatin and labeled them with letters A,B,C,D,E and F, which we will use further n as names. Letter A dentes the target advertisement. All brand lgs used fr the game had nly tw dminant clrs and their mmentums1 were reasnably high and 1 The mmentum f a brand is a measure fr its image and ppularity and was btained frm the BrandZ Ranking Reprt 2010 [12]

4 similar t each ther (2 advertisements each with 6,7 and 8, respectively). A belnged t the grup with the lwest mmentum (6). The psitins f the advertisement billbards were selected in a way t btain a reasnable variatin in screen space. T cunterbalance ptential bias due t psitin effects, the psitin f adverts was shifted between participants in a circle (A t psitin f B, B t psitin f C, and s n) such that in each cnditin, tw (ut f twelve) participants saw the same arrangement. Sme artistic freedm was, hwever, necessary t design a scene with representative aesthetical prperties and maximize cngruity with the cntext. Realism and embeddedness f the advertisements was increased by adding further advertisement billbards which were nt related t any brands r prducts (e.g., an advertisement against wearing fur) and were nt cnsidered in the memry test. The yaw-angle f the billbards textured with advertisements varied with angles between -12 and +14 degrees t the image plane, whereas the pitch-angle was zer fr all surfaces. Height and width f the advertising elements varied between (x min = 80,y min = 40) and (x max = 120,y max = 80) pixels in the screen-space prjectin. The scenes were rendered with a ray tracer (Vray) after the textures f advertising elements were added. The reslutin used fr rendering was 2,700 1,400 pixels with a pixel aspect rati f 1.0, and then rescaled with an image prcessing tl t fit t the maximum reslutin and aspect rati f the display used in the experiment Cnditins We designed three cnditins t be tested in this study: TEST: In this cnditin, the health item shield (Health Item 1 in Figure 1) was designed such that it shared several features with target advertisement A: the shield clr and the clr, curvature and rientatin f the banana drawn n the shield resemble tw glyphs in the lg letter f A. CTRL 1: The first cntrl cnditin is identical t the TEST cnditin, apart frm using a different health item, a purple shield with a pink blueberry (Health Item 2 in Figure 1). We used this cnditin t cntrl the self-efficacy f the advertisements and the pssible explanatin that a ptentially higher saliency r ppularity f A might have caused the measured effects. CTRL 2: This cnditin was similar t the TEST cnditin, with the difference that A was replaced by anther advertisement A (with same mmentum). This secnd cntrl cnditin was required t cntrl effects n ther advertisements which are due t the differences in the design f the health items, and t cntrl a ptential influence f the feature similarity between Health Item 1 and A n the recgnitin f A in ur memry test. Mrever, we can cmpare the effects f advertising fr A and nt advertising fr A Participants 38 participants (6 female) aged between 17 and 38 (mean = 24.3, stddev = 4.0) vlunteered fr this study. Each participant was assigned t ne cnditin, which was determined randmly befre the participant shwed up fr the experiment. All except tw participants (i.e., 36) were naive abut the real purpse f the study, and in case f questins they were tld that the study is cncerned with reactin times in vide games. The tw participants wh guessed the actual purpse befre the experiment were excluded. As the verall prcedure can nly be perfrmed nce per participant (withut a significant bias f behavir in a secnd trial), it was necessary t use a between-subject paradigm, testing each participant in nly ne f the three cnditins. Cnsequently, each f the three cnditins was run with 12 participants. All participants had nrmal r crrected-t-nrmal visin. Nne f them had any type f clr blindness Memry Test The memry test participants had t perfrm was run with a separate applicatin with the fllwing prcedure: in each trial the applicatin displayed three advertising elements. One f them had actually been displayed in the game, while the ther tw were distractrs which had nt appeared in the game. T als include effects n subcnscius memry, we used a frced-chice paradigm, and participants were instructed t guess in case they had difficulties t remember. All in all, a participant had t select 36 times ne ut f three advertisements. A ttal f 12 distractr advertisements was used in rder t make sure that each advertisement (distracting and in-game advertisement) appeared with the same frequency (6, that is 2 times at each f the 3 lcatins). The distributin f their mmentums was similar t that f in-game advertisements mmentums. Thugh target advertisement A did nt appear in cnditin CTRL 2 (being replaced by A ), we still tested fr recgnitin f A fr participants f this grup since we were interested if the similarity between the brand design f A and the health item has an impact n brand recgnitin withut the actual advertisement being present. T avid bias due t a difference in the number f trials, we did nt include further trials t test whether the replacement, A, was remembered. The cmbinatins were rdered s that repetitins f advertisements in tw subsequent trials were avided and the ccurrence frequency f each advertisement was apparently chatic but still reasnably balanced ver time. All participants f the study ran thrugh the same sequence f trials.

5 *) mean scre TEST CTRL 1 CTRL 2 chance level A E B D F C distributin f scres *) A E B D F C *) A absent!! Fig. 3. Results: the average scres are pltted n the left, and the accrding distributin was visualized with bx plts n the right side. The dtted line in the backgrund crrespnds t the expected value fr randm guessing Prcedure The game was played n a Sny Vai VPCEB1S1E ntebk running Windws 7, equipped with ATI Mbility graphics hardware and a 15.5 LED TFT display with 16:9 frmat and 1, pixels reslutin (a display size that is typical fr many casual gaming situatins). The experiments were carried ut in a sufficiently dimmed rm t avid reflectins n the screen using the fllwing prtcl after a participant has been intrduced t the game: Playing (3 minutes): The game was timed with a stp watch. In case f a game-ver, the watch was paused until the game was restarted. Distractin (6 minutes): Participants filled a dummy questinnaire and, additinally, were asked sme questins rally that required them t access cntent f their episdic memry (e.g., What was the first cmputer game yu ever played? ). The purpse was t distract them frm the game experience s that the subsequent memry test did nt access shrt-term memry. Memry test (4 minutes n average): 36 trials (6 per each advertisement in the game) 5. RESULTS We visualized the results in Figure 3, pltting the mean scres and the distributins as bx-plts. Fr statistical analysis (Table 1), we cmputed an exact Wilcxn rank sum fr pairwise cmparisns f the scres between test cnditin (TEST) and cntrl cnditins (CTRL 1 and CTRL 2). Nn-parametric tests were indicated due t significant vilatins f nrmality and equality f variance assumptins, which are als bvius in the bx plts shwn in Figure 3. In the fllwing we summarize ur main cnclusins: Between cnditins (exact Wilcxn rank sum test, ne-tailed, N = 2x12) Alt. Hypth. Advertisement (1st and 2nd clr) A (yellw/red) E (blue/yellw) B (white/red) TEST>CTRL , p = , p = , p =.007 D (blue/white) F (black/white) C (blue/white) 95, p = , p = , p =.62 A (yellw/red) E (blue/yellw) B (white/red) TEST>CTRL , p < , p = , p = 0.14 D (blue/white) F (black/white) C (blue/white) 82, p =.30 78, p =.37 63, p =.71 Table 1. Statistical evaluatin f the pairwise differences between cnditins fr each advertisement. We listed the W-values tgether with the respective p-values. Denting clrs f the respective advertisements (fregrund clr/backgrund clr) shuld emphasize ptential effects f clr similarity (with the yellw/red health item). Bad memry withut manipulating attentin: The results fr CTRL 1 shw that withut attentinal manipulatin, the perfrmance in the memry test was arund chance level (33%) even thugh participants were expsed 3 minutes t the advertisements. Cncerning in particular the results fr A, there was almst n difference between CTRL 1 and CTRL 2, even thugh A was absent in CTRL 2. Testing the hypthesis H 1 that recgnitin f A is better in CTRL 1 cmpared t CTRL 2 gave an insignificant result (exact Wilcxn rank sum: W = 81.5,p = 0.3). This means that withut attentinal manipulatin, the effectiveness f advertising fr A was barely better than nt advertising fr A (in a game where a health item sharing abstract features with A is present). Highly significant effect fr advertisement A: While the average scres fr A in the TEST cnditin are arund 90%, they are arund chance level in the cntrl cnditins. Regarding the results fr the statistical tests (Table 1), we can accept ur alternative hypthesis that attentin was effectively directed t advertisement A n a highly significant level (p =.0003). Better memry als fr ther advertisements than A: Remarkably, als advertisements apart frm A were remembered best in TEST. T a certain degree, this can be explained by Guided Search: Advertisement E shared the yellw clr and B the red clr with the health item. Hence, scres in TEST and CTRL 2 were better than in CTRL 1, where the health item was neutral. Even mre surprising is that the scres f E,B,D and F were als smewhat better in TEST than in CTRL 2, thugh the same health item was used. The differences are nt significant (Table 1), but we suspect a trend in this directin and ur guess is that a strng attentinal link between a player s tasks and the backgrund als increases the prbability that ther details get nticed. N bservable effect n gaming perfrmance: We als investigated whether there were any negative effects f the tested methd n gaming perfrmance. Therefre we listed the mean f game pints and game-vers per cnditin (Ta-

6 TEST CTRL 1 CTRL 2 pints 2465 ± ± ± 376 number f game-vers 1.27 ± ± ± 1.0 Table 2. Gaming perfrmance (mean and standard deviatin). ble 2). Surprisingly, the number f game pints was highest in the TEST cnditin, but the effect f cnditin was nt significant (ANOVA: F(2,33) = 1.41, p = ). The number f game vers was marginally lwest in the CTRL 1 cnditin, but the effect f cnditin was nt significant at all (Kruskal- Wallis:χ 2 = 0.1, p = ). 6. CONCLUSION AND FUTURE WORK This study shws that the visual design f task-relevant items, at least f thse which are searched frequently, has a significant effect n the recgnitin f a game s envirnment. Withut feature similarity with task-relevant search targets, elements in the backgrund remain unnticed (cnditin CTRL 1), at least users are nt able t remember them. Whereas, in case f a strng similarity (cnditin TEST), the respective elements enter a user s memry. Als, with increasing degree f similarity (advertisements E and B in TEST and CTRL 2) t the search target, the perfrmance in the memry test tends t increase. Hwever, thugh we did nt bserve a negative effect n task perfrmance in this study, directing attentin twards advertisements actually cntradicts the gals f a player, wh wants t find task-relevant items rather than advertisements. Prbably, at sme pint where this methd is applied t intensively, visual distractin may significantly hinder game play. Hwever, this culd als be a strategy t vlitinally increase the difficulty f a game level, with an increased effectiveness f advertising as side effect. This wrk shuld als be a starting pint fr the explratin f new avenues fr the reverse applicatin f visual attentin mdels. Fr example, the prpsed guiding principle wuld als wrk t avid inattentinal blindness t ther targets than advertisements and find utility fr a perceptually ptimized game design where unexpected but task-relevant bjects are less ften verseen by the users. As this study was preliminary, we maximized the strength f the effect and used 4 features in cnjunctin (yellw clr, red clr, rientatin and curvature). Since yellw and red are salient clrs, the effect f clr has prbably dminated in this study. Hwever, the clarity f the results shuld mtivate future wrk t investigate hw well the apprach wrks fr less salient features and less bvius similarities. Therefre, 2 A Shapir-Wilk test n residuals and a Levene test shwed that nrmality and equality f variance assumptins were nt vilated and thus a parametric test culd be used. 3 As the number f game vers was distributed ver very few discrete values, nrmality culd nt be assumed and a nn-parametric test was necessary. ne shuld investigate the effect f particular clrs, features and cmbinatins f features by means f a multi-factrial experimental design and analysis. Mrever, the game was (apart frm the backgrund) in 2D with a fixed viewpint, and further studies with games where the viewpint varies cnsiderably are necessary. 7. REFERENCES [1] I.M. Chaney, K.-H. Lin, and J. Chaney, The effect f billbards within the gaming envirnment, J. f Int. Advert., vl. 5, n. 1, pp , [2] Shawn C. Green and Daphne Bavelier, Actin vide game mdifies visual selective attentin, Nature, vl. 423, n. 6939, pp , [3] J. Mack and I. Rck, Inattentinal Blindness, The MIT Press, Cambridge, MA, [4] J.M. Wlfe, Guided search 2.0: A revised mdel f visual search, Psychnmic Bulletin and Review, vl. 1, n. 2, pp , [5] M. S. El-Nasr, T. Vasilaks, C. Ra, and J. Zupk, Dynamic intelligent lighting fr directing visual attentin in interactive 3d scenes, IEEE Trans. Cmp. Int. and AI in Games, vl. 1, n. 2, pp , [6] R. Bailey, A. McNamara, N. Sudarsanam, and C. Grimm, Subtle gaze directin, ACM Trans. Graph., vl. 28, n. 4, pp. 1 14, [7] B. Lewis and L. Prter, In-game advertising effects: Examining player perceptins f advertising schema cngruity in a massively multiplayer nline rle-playing game, J. f Int. Advert., vl. 10, n. 2, pp , [8] P.N. Dixit and G.M. Yungbld, Optimal infrmatin placement in an interactive 3d envirnment, in Sandbx 07: Prc. f the 2007 ACM SIGGRAPH Symp. n Vide Games, 2007, pp [9] A. Melzer, B.J. Bushman, and U.G. Hfmann, When items becme victims: Brand memry in vilent and nnvilent games, in Entertainment Cmputing - ICEC: 7th Int. Cnf. 2008, pp , Springer. [10] A.M. Treisman and G. Gelade, A feature-integratin thery f attentin, Cgnitive Psychlgy, vl. 12, n. 1, pp , January [11] Daniel Memmert, The effects f eye mvements, age, and expertise n inattentinal blindness., Cnsciusness and Cgnitin, vl. 15, n. 3, pp , [12] BrandZ, 2010 full reprt,