The effects of emotion priming on visual search in socially anxious adults

15 Pages·2016·1.98 MB·English

by  Sara A. Haas

Cognition and Emotion
ISSN: 0269-9931 (Print) 1464-0600 (Online) Journal homepage: http://www.tandfonline.com/loi/pcem20
The effects of emotion priming on visual search in
socially anxious adults
Sara A. Haas, Dima Amso & Nathan A. Fox
To cite this article: Sara A. Haas, Dima Amso & Nathan A. Fox (2016): The effects of
emotion priming on visual search in socially anxious adults, Cognition and Emotion, DOI:
10.1080/02699931.2016.1180281
To link to this article: http://dx.doi.org/10.1080/02699931.2016.1180281
Published online: 19 May 2016.
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Download by: [50.181.76.89] Date: 20 May 2016, At: 07:43
COGNITIONANDEMOTION,2016
http://dx.doi.org/10.1080/02699931.2016.1180281
BRIEF ARTICLE
The effects of emotion priming on visual search in socially anxious adults
Sara A. Haasa, Dima Amsob and Nathan A. Foxa
aDepartmentofHumanDevelopmentandQuantitativeMethodology,UniversityofMaryland,CollegePark,MD,USA;bCognitive,
Linguistics,andPsychologicalSciences,BrownUniversity,Providence,RI,USA
ABSTRACT ARTICLEHISTORY
Thisstudyexaminedtheeffectsofemotionprimingonvisualsearchinparticipants Received15September2015
characterised for different levels of social anxiety. Participants were primed with Revised25January2016
five facial emotions (angry, fear, happy, neutral, and surprised) and one scrambled Accepted14April2016
face immediately prior to visual search trials involving finding a slanted coloured
KEYWORDS
line amongst distractors, as reaction times and accuracy to target detection were
6 recorded. Results suggest that for individuals low in social anxiety, being primed Threat;socialanxiety;visual
1 search;emotion;selective
20 with an angry, surprised, or fearful face facilitated visual search compared to being attention;facialexpressions
y primed with scrambled, neutral or happy faces. However, these same emotions
a
M degraded visual search in participants with high levels of social anxiety. This study
0 expands on previous research on the impact of emotion on attention, finding that
3 2 amongst socially anxious individuals, the effects of priming with threat extend
4 beyondinitialattentioncaptureordisengagement,degradinglatervisualsearch.
7:
0
at
]
9
6.8 Themechanismsunderlyingthefearsystemservean attentional bias as a function of context. Individuals
1.7 adaptive function, allowing individuals to rapidly who previously received shock in one context dis-
18 detect threat in the environment and mount an played avoidance using the dot probe compared to
0. appropriate response (Bar-Haim, Lamy, Pergamin, others who had not previously received the shock.
5
y [ Bakermans-Kranenburg, & van IJzendoorn, 2007; Emotional context, thus, appears to influence the
b
d Öhman, 2005). However, hypervigilant processing of mannerinwhichthreatisdetectedandrespondedto.
de threat – a heightened tendency to direct attention Two paradigms commonly used to evaluate the
a
nlo preferentially to threatening stimuli – is often found effects of threatening stimuli on attention are the
w in anxious individuals (MacLeod, Mathews, & Tata, dot-probe task and face-in-the crowd task. In the
o
D 1986; Mathews, Mackintosh, & Fulcher, 1997; dot-probe task, participants are instructed to press a
Mathews & MacLeod, 1985; Mogg, Mathews, & button indicating the location of a target, which
Eysenck, 1992). This attention bias to threat has appears in a location previously occupied by one of
been found in both clinically and non-clinically two faces. One of these faces typically expresses a
anxious individuals in a wide variety of tasks, and neutral emotion and the other, a negative emotion,
maybeinvolvedinboththedevelopmentandmain- suchasanger.Studiesusingthedot-probeparadigm
tenanceofanxietysymptoms(Bar-Haimetal.,2007). have noted the presence of an attention bias to
Thereis,however,evidencetosuggestthatstress- threat in individuals with anxiety disorders (Bar-Haim
fulcircumstancesalteranxiousindividuals’pattern of et al., 2007). Specifically, increased anxiety is associ-
attention to threat. Bar-Haim et al. (2010), for ated with an enhanced bias or vigilance to detect
example, found that anxious individuals under acute targets that appear in the same location as threaten-
threat displayed attentional avoidance as measured ing faces (angry faces) or words compared to non-
with the dot-probe task, rather than a bias towards threatening faces (happy or neutral) compared to
threat. In addition, Shechner, Pelc, Pine, Fox, and non-anxiousparticipants(Amir,Elias,Klumpp,&Prze-
Bar-Haim (2012) reported on the plasticity of worski, 2003;Mogg &Bradley, 2002;Mogg, Philippot,
CONTACT SaraA.Haas [email protected]
©2016InformaUKLimited,tradingasTaylor&FrancisGroup
2 S.A.HAASETAL.
&Bradley,2004).The“face-in-thecrowd”paradigm,a In another priming study utilising the dot-probe
type of visual search task, requires participants to task, Helfinstein, White, Bar-Haim, and Fox (2008)
identify faces amidst distractors (e.g. an angry face studiedadultsselectedforhighandlowself-reported
among an array of happy faces). In this task, individ- social anxiety symptoms, priming them with words
uals with social anxiety are also quicker during either conveying relevant affective meaning (e.g.
searchtodetectthreateningfacesamongstotherdis- shy, embarrassed) or neutral words, before each trial
tracting stimuli compared to happy or neutral faces onthedotprobetask.Theyfoundthatwhensubjects
(Gilboa-Schechtman, Foa, & Amir, 1999; Gilboa- with high reported social anxiety symptoms were
Schechtman, Presburger, Marom, & Hermesh, 2005; primed with affective words, they did not display a
Ohman,Flykt,&Esteves,2001). biastowardsthreat,however,theydisplayedathreat
Thesestudiesgenerallyexaminegroupdifferences bias after being priming with neutral words. Conver-
inattentionmechanismsinvolvedinemotionproces- sely, when subjects with low reported social anxiety
sing. However, a second line of work has focused on symptoms were primed with affective words, they
theimpactemotionprimingmayhaveonsubsequent showed an attention bias to threat that was not
attention. Several studies have demonstrated that present when primed with neutral words. Thus,
early visual processes are affected by emotion emotionprimingappearstodifferentiallyimpactsub-
16 primes, fearful primes in particular, and these effects sequent attention processes as a function of anxiety
0
2 are lasting. Neural evidence from steady state visual symptomsinsub-clinicalsamples.
y
a evoked potentials (ssVEP), thought to originate in Anumberofstudieshavealsofoundthatemotion
M
0 early visual cortical regions, has demonstrated that a primingfacilitatesvisualsearchfortargetsembedded
2 fearful cue facilitates identification of threat (Wieser in an array of distractors. For example, Becker (2009)
3
4 & Keil, 2014). When a scene containing threat is pre- found that when individuals are primed with fearful
7:
0 ceded by a fearful face expression, ssVEP’s to the expressions prior to completing a non-valenced
] at threat scene increase, compared to other scenes visual search task (e.g. looking for a picture of a
9
8 (Wieser & Keil, 2014). Phelps, Ling, and Carrasco house amid other common stimuli such as planes
6.
7 (2006) also demonstrated that fearful expressions andcars),searchperformanceimproves.Theimprove-
81. havethecapabilityofalteringearlyvision,specifically, ment relative to neutral face-primed performance
1
0. contrast sensitivity. Compared to trials preceded by becomesmorepronouncedasthenumberofdistract-
5
[ neutral faces, trials preceded by fearful faces ingstimuliincreasesinsearcharrays(seealsoOlatunji,
y
b lowered the contrast sensitivity threshold necessary Ciesielski, Armstrong, & Zald, 2011 with consistent
d
e detect the orientation of the subsequent target findings). In the classic visual search literature,
d
oa Gabor stimuli. The observed advantage for trials pre- addingdistractorstosearcharraysresultsinincreases
wnl cededbyafearfulfaceinearlyvisualprocessing,was in reaction times or search slopes (Weierich, Treat, &
Do particularly pronounced for the condition in which Hollingworth, 2008). Seeing a fearful face results in a
the emotion cues appeared in a single peripheral flattening of search slopes, or faster target detection
location, as opposed to distributed in each of the than would be expected in the absence of the
four possible target locations (Phelps et al., 2006). In fearfulfaceprime.Inanoddballvisualdetectionutilis-
a subsequent study, Ferneyhough, Kim, Phelps, and ingthesamevariationsinnumberofdistractorstimuli
Carrasco (2013) replicated the findings of Phelps as Becker (2009), Quinlan and Johnson (2011) found
et al. (2006) in subjects who reported low trait that participants are fastest to detect threatening
anxiety characteristics. However, subjects who stimuli compared to non-threatening stimuli when
reported high trait anxiety characteristics displayed trials are repeatedly preceded by a fearful cue com-
compromisedcontrastsensitivityontrialswhereaper- paredtobeingrepeatedlyprecededbyaneutralcue.
ipheralfearfulfacewasfollowedbyadisplayinwhich Thefindingsoftheseprimingstudiescanbeinter-
thetargetGaborpatchwasinadifferentlocationfrom preted in the context of a two-step threat detection
the original prime. The attentional cost of diverting model: first, attention is engaged by threat-cueing
attention away from the fearful cue in order detect stimuli, quickly followed by a second stage in which
the orientation of the target Gabor, proved costly for thereisincreasedcapacityforrapidorientingandper-
the visual perception of individuals who scored ceptionofotherstimuli(Becker,2009).Inlinewiththis
highestontraitanxiety(Ferneyhoughetal.,2013). model, Becker (2009) suggested that fearful facial
COGNITIONANDEMOTION 3
expressions, and other threat-cueing stimuli, might 2011). In the initial examination of the paradigm
modulate attentional orientating by reallocating used for the current study, we chose to examine
attention faster to scanning the environment in socialanxietycharacteristicswithinasubclinicalpopu-
searchofimmediatethreat. lation, as this type of anxiety may be the most sensi-
Indeed, differences in vigilance have been tive to priming effects of facial expressions. Our
suggested as contributing to patterns of anxiety. novel search task may allow greater insight into the
While there are costs in early visual processing for specific attention components that influence
high trait anxious individuals reported by Ferney- emotional processing in anxious individuals. That is,
hough et al. (2013) when primed with fearful cues, while the dot-probe task has captured patterns of
visualsearchperformance,is notclearly facilitated or attention bias in anxiety,itis notclear ifthereaction
hindered by fearful cues as a function of higher trait time measures reflect initial orienting to threat, diffi-
anxiety (Olatunji et al., 2011). Olatunji et al. (2011) culty disengaging form threat, or a general vigilance
replicatedBecker’s(2009)findingsthatfearfulprimes to threat cues in the environment (Weierich et al.,
facilitate more efficient visual search, however no 2008). Because the current task includes a condition
such facilitation nor deterioration was observed for comparable to the dot-probe task, as well as several
individuals who displayed higher characteristics of visualsearchsetsizes,thistaskallowsustodisambig-
16 traitanxiety.Itmaybethattasklimitations,specifically uatetheseprocessesbyseparatingemotionexposure
0
2 lack of a variety of set sizes (each visual search array from the visual search task. None of the aforemen-
y
a contained 12 items), restricted the ability to detect tioned visual search priming tasks included such a
M
0 clear individual differences in priming effects as a condition.Moreover,Olatunjietal.(2011)andOlatunji
2 function of anxiety symptoms. In a follow-up study et al. (2015), presented the priming cue immediately
3
4 examiningagroupofveteranshighinposttraumatic prior to each visual search, with no time to allow for
7:
0 stressdisorder(PTSD)symptoms,andacontrolgroup, the extinguishing of attention capture, or disengage-
] at Olatunji,Armstrong,Bilsky,andZhao(2015)foundno ment effects. The current study follows the timing of
89 differencesinvisualsearchperformancebetweenthe Becker’s (2009) and Quinlan and Johnson’s (2011)
6.
7 PTSDandcontrolgroupswhensubjectswereprimed tasks, which both include 600milliseconds inter-
1.
8 withfearfulfaces,however,thehighPTSDgroupwas stimulus intervals (ISI) between the priming cue and
1
0. significantly slower to detect the target during the search arrays. Without both a set-size comparable to
[5 moderately difficult visual search array when primed thedot-probeparadigm,aswellasinISItoextinguish
y
b with an angry prime, as compared to the control attention capturing/disengagement effects, it is
d
e group.Whilecueimpactmayvarybyanxietysympto- impossible to discern whether differential visual per-
d
oa mology, it appears that threat-related cues across a formanceisduetotheemotionprimedirectlyimpact-
wnl variety of anxiety measures and priming tasks, have ing attentional orienting, or simply measuring the
Do thecapabilitytohavecostlyeffectsonvisualsearch. amount of time it takes the participant to disengage
Toaddtothecurrentliteratureexaminingpriming fromtheemotionprime.
effectsonattentionacrosstheanxietycontinuum,we In this study, participants were primed with five
examined the impact of priming on attention as a facialemotionexpressions(angry,fear,happy,neutral,
function of anxiety by designing a task in which and surprised) and one scrambled face immediately
emotional faces were used as primes for a visual prior to every visual search trial, as reaction times to
search task. Of specific interest was examining how identify each target was recorded. Two baseline com-
performanceonthisnewtaskmightvaryasafunction parison conditions were included: neutral faces and
of social anxiety characteristics, thus expanding our scrambled faces. We included the surprised emotion
understanding of attention in the context of threat. asresearchindicatesthathighsociallyanxiousindivid-
Several studies have demonstrated reaction time ualsinterpretsurprisedfacesasthreatening(Kimetal.,
and attentional performance differences on emotion 2004;Richardsetal.,2002).Thismaybeduetopercep-
cueingvisualattentiontasksasafunctionofsub-clini- tual similarities between surprised and fearful facial
cal levels of anxiety (Ferneyhough et al., 2013; Fox, expressions (raised eyebrows, wide eyes, and open
Henderson, Rubin, Calkins, & Schmidt, 2001; Helfin- mouth), as well as the ambiguity of a surprised
stein et al., 2008; Koster, Crombez, Verschuere, & De expression. Indeed, studies that have investigated the
Houwer, 2006; Macleod & Mathews, 1988; Mogg, valence interpretation of surprised faces have shown
Holmes, Garner, & Bradley, 2008; Olatunji et al., that they are not consistently rated as either positive
4 S.A.HAASETAL.
or negative, and are dually valenced and ambiguous the impact of emotion on attention functions. While
(Neta,Davis,&Whalen,2011). Becker (2009), Olatunji, Armstrong, McHugo, & Zald,
Angrywasincludedasthisemotionhasbeenused 2013, and Quinlan and Johnson (2011) utilised a
commonly in dot-probe paradigms as the “threaten- variety of set sizes, these set sizes did not exceed 12
ing” emotion, and demonstrated differences in reac- items, limiting the interpretability of how visual
tiontimeperformanceonthesevisualattentiontasks search efficiency changes as a function of increasing
as a function of differences in anxiety levels demands in various emotional contexts. Moreover,
(MacLeodet al., 1986; Mathews etal.,1997;Mathews Olatunjietal.(2011)andOlatunjietal.(2015)utilised
& MacLeod, 1985; Mogg et al., 1992). While angry reactiontimefortheparticipanttonavigatehisorher
facesandfearfulfacesbothsignalthreat,fearfulfaces mouse cursor to the target location on the screen as
indicateambiguity,suchthatthelocationofthreatis thedependentmeasureofvisualsearchlatency,limit-
not known. We included the fearful face in efforts to ing the specificity and sensitivity of the results of
replicate similar findings by Becker (2009), Phelps actual subject latency to detect the target location.
etal.(2006),andFerneyhoughetal.(2013),whoeach Therefore, we varied the number of distractors used
foundthatwhenprimedwithfearfulfacialexpressions, for visual search, ranging from no distractors, up to
visualattentionimproved(visualsearchimprovement: 29 distractors. As the number of distractors increase,
16 Becker, 2009; low level contrast sensitivity improve- an individual must sample more possible target
0
2 ments: Phelps et al., 2006; and Ferneyhough et al., locations, leading to longer target detection times. If
y
a 2013). Moreover, Ferneyhough et al. (2013) found threatening emotional contexts differentially affect
M
0 that individuals with high trait anxiety experienced attentionalorientingprocessesinsociallyanxiousindi-
2 deteriorationincontrastsensitivitywhenprimedwith viduals,thereshouldbedifferencesintheslopeofthe
3
4 fearfulfaces,whilelowtraitanxiousindividualsexperi- visual search asafunctionofthe emotion prime and
7:
0 encedenhancedcontrast-sensitivity. social anxiety (Treisman, 1986). Slope refers to the
] at A concern for a number of the tasks previously reaction time cost to detect the target as a function
9
8 mentioned, including the dot-probe, face in the of increasing the number of distractors (Treisman,
76. crowd, visual search, and contrast sensitivity tasks, is 1986). We predicted that similar to the findings
1.
8 the use of neutral faces for the comparison or reported by Olatunji et al. (2011), Olatunji et al.
1
0. control condition. The logic behind using a neutral (2015), Quinlan and Johnson (2011), Phelps et al.
5
[ face is that a neutral face contains all of the percep- (2006), Ferneyhough et al. (2013), and Becker (2009),
y
b tual features, as other emotions, but do not convey that for participants in the normal or low range of
d
e valence. However, there have been discrepant find- reported in social anxiety symptoms, being primed
d
oa ings with respect to how neutral faces modulate with threat-relevant cues would facilitate visual
wnl visual attention as a function of anxiety (Cooney, search performance (e.g. smaller slope, indicating
Do Atlas,Joormann,Eugène,&Gotlib,2006;Ferneyhough reduced reaction time costs when more distractors
et al., 2013). Cooney et al. (2006) found that individ- are added). Based on the literature demonstrating
ualswithsocialanxietydisplayedanegativeinterpret- deterioration in visual attention across a variety of
ation bias towards neutral faces, and displayed attentional tasks and anxiety dimensions (Amir et al.,
heightened patterns of amygdala activation to 2003; Ferneyhough et al., 2013; Gilboa-Schechtman
neutral faces compared to a control group (Cooney et al., 1999, 2005; Helfinstein et al., 2008; Mogg &
et al., 2006). Neutral faces may not be an ideal Bradley, 2002; Mogg et al., 2004; Ohman et al., 2001;
control condition to examine the effects of emotions Olatunjietal.,2011,2015),wepredictedthatforpar-
on visual attention when studying anxious individ- ticipants scoring higher on social anxiety measures,
uals. To address this concern, we included a threatening faces would degrade visual search per-
scrambled face as a control. A scrambled face formance(e.g.largerslope,indicatingincreasedreac-
stimuli contains all the components of a face, tiontimecostswhenmoredistractorsareadded).The
however do not allow the participant to perceive an major aims of this study were to further clarify
actualfaceoranytypeofemotion,makingitapoten- whether previous findings of costly visual attentional
tially better comparison condition or baseline than control when primed withthreateningimagesreflect
the commonly used neutral face. initial alerting or attention capture, examine which
In addition, by manipulating the processing load emotional contexts affect attention similarly to
via the distractor presence we can better capture reported threatening emotional contexts, as well as
COGNITIONANDEMOTION 5
examine whether these emotional contexts addition- Table1.Correlationofself-reportedanxietyquestionnaires.
allyaffectlatervisualattentionalprocesses,specifically Measure LSAStotal STAIstate STAItrait
attentionalorientingduringavisualsearch. STAI-STATE .620** –
STAI-TRAIT .776** .661** –
PSWQ .583** .406** .755**
Methods **p<.01.
Participants
throughtheonlinesurveysystemandduringthelab-
Participants were recruited based on their self-report oratory visit were highly correlated r (66)=.79, p
answer on the Liebowitz Scale of Social Anxiety <.001. The State portion of the State Trait Anxiety
(LSAS) (Heimberg et al., 1999) through an online Inventory (Spielberger, 1977) was also obtained at
survey system. Participants received psychology the time of testing for use in analyses to control for
course credit and agreed to be contacted for future state anxiety at the time of the study (see Table 1).
studies based on their scores. From the 776 students The State Trait Anxiety inventory was only adminis-
thatcompletedtheLSAS,meanLSASscorewascalcu- tered during the laboratory visit, not the online
lated, and participants were recruited based on ±1 surveyutilisedforscreenpurposes.Thelaboratorycol-
6 standarddeviationfromthemean(M =45).Partici- lected LSAS scores of the entire sample (n=77), did
01 pantswhoscoredbelow22,oraboveLS6AS8ontheLSAS not violate normality tests, and fit a normal distri-
2
y were invited to participate in the study. To achieve bution rather than a bimodal distribution (even
a
M amplesamplesize,thestudywasopeneduptoallUni- though we did initially attempt to select to acquire
20 versity of Maryland students enrolled in Introduction extremegroups)(seeFigure1andTables1and2).
3
4 to Psychology, and an additional unselected 11 sub-
07: jects who had not completed any part of the survey
at participated. For these subjects, the LSAS adminis- Face stimuli
]
89 teredatthetimeoftesting. 80 pictures of facial expressions were selected from
76. A power analysis conducted in G*Power 3.1 esti- the NimStim Inventory (Tottenham et al., 2009). The
81. matedthat85participantswereneededtoachievea selection of NimStim faces used for this paradigm
0.1 powerof.95(amoderateeffectsize,baseduponpre- was based on the following criterion: NimStim faces
[5 viousstudieswithd=.5)whencarryingouta2-group, that had comparable luminance, no visible jewellery,
by 6 within-subjects conditions Linear Mixed Model
ed (LMM). The final sample included 77 adults (24
d
a males) between the ages of 18 and 34 (M=21.62,
o
nl SD=3.16).Self-reportedracewasasfollows:62%Cau-
w
o casian, 21%Asian,8% AfricanAmerican, 5% Hispanic
D
and4%ofparticipantschosenottoanswer.Threepar-
ticipants who did not complete the entire visual
search task were excluded from all further analyses,
resulting in a final sample of 74 participants (22
males). The University Institution Review Board
approved all procedures and participants of the
study received verbal and written informed consent
inaccordancewiththeseprocedures.
Questionnaires
The LSAS was administered on-line and again when
subjects came to the lab for the study. The mean
elapsed time of completion of LSAS between time 1
(pre-selection of the participants) and time 2 (the
actualstudy)wasM=39.6days,SD=18.28days,and
ranged from 3 to 72 days. LSAS scores obtained Figure1.HistogramofLSASscores.
6 S.A.HAASETAL.
Table2.Anxietyquestionnairesdescriptives.
Questionnaire Z-scoremin. Z-scoremax. Rawmean Std.dev. Min. Max. Skewness Std.error Kurtosis Std.error
LSAStotal −1.66 2.45 53.39 29.07 5 125 0.37 0.27 −0.71 0.54
STAI-STATE −1.62 3.32 38.05 10.47 21 73 0.85 0.27 0.63 0.54
STAI-TRAIT −1.78 2.84 41.27 10.78 22 72 0.73 0.27 0.32 0.54
PSWQ −1.98 1.65 53.22 13.69 26 76 −0.17 0.27 −1.15 0.54
comparable face size, comparable head tilt angle, the 8 female actors, and one full set for the 8 male
minimal hair on face/facial hair, and included a actors,aswellastwiceforthescrambledfacecondition.
varietyofraces.Thepicturesdepictingtheemotional Thisresultedin64trialsforeachofthe6conditions.X
faceswereallpresentedatasizeof2by3in.andcen- andYcoordinatesofeverydistractoritemineachvisual
teredonthecomputerscreensothatthenoseofthe search were randomly assigned using randomizer.org
stimulus replaced the previously presented crosshair. (seeFigure2(b)).
All faces were grey scaled, and cropped to fit with in Inadditiontothesetrials,therewere24catchtrials
a 2 by 3in. oval, thus controlling for variations in in which therewasnoactual target present, andpar-
colour (Blau, Naurer, Tottenham, & McCandliss, 2007) ticipantsweretoldtodonothing(asopposedtopress-
6
1 (see Figure 1(a)). The racial breakdown of the faces ing the spacebar). These catch trials were inserted
0
2 for males included: two black, one Hispanic, and five randomlyasanattentionchecktomakesurethatpar-
y
a whitefaces.Forfemalefaces:twoblack,oneHispanic, ticipantswereappropriatelycompletingthetask.Catch
M
0 oneAsian,andfourwhitefaces.TheselectedNimStim trialsconsistedof8trialswith5distractors,8trialswith
2
3 actor numbers were as follows: f03, f05, f06, f07, f09, 15 distractors, and 8 trials with 30 distractors. Partici-
7:4 f11, f13, f18, m23, m24, m26, m27, m34, m37, m41, pantscompletedatotalof528visualsearchtrials.
0 m42. These included five pictures of eight female
at
] actors with angry, fearful, happy, neutral, and sur- Visual search task
9
8 prised expressions and five pictures of eight male
6.
7 actors expressing the same emotions (see Figure 2 The task was presented using E-Prime 2.0 stimulus
1.
8 (a)). The scrambled face used, designed by Katoni presentation software on a Dell laptop with an
1
0. (2012), was a picture of a female actor presenting a attached 1080×1024 resolution monitor and key-
5
y [ neutral face, divided into various small squares and board.Eachtrialconsistedofafacestimuluspresented
b changing the position of each square so that the for 300milliseconds, followed by a black crosshair
d
de face appeared scrambled (see Figure 2(a)). Moreover, centred on a gray background for 600milliseconds.
oa these faces never overlapped with the locations of The visual search task was then presented for 2000
wnl any of the visual search targets – this was to insure milliseconds, or until the participant responded by
Do that no target location was inhibited or primed by pressing the space bar. The trial ended with another
priorvisualstimuli. black fixation on a gray background presented for
500milliseconds (see Figure 1(c)). The timing of the
presentationwasmodelledafterBecker(2009).Partici-
Visual search stimuli
pantswereinstructedtopressthespacebarassoonas
Intheconjunctionvisualsearchparadigm,participants they identified a black slanted target, or let the trial
wereaskedtofindablackslantedbaramongstasetof passbyiftheydidnotdetectablackslantedbar.Par-
distractors.Thedistractorsincludedwhiteverticalbars, ticipants were not given any a priori information
white slanted bars, and black vertical bars. Set size regarding the face primes in an effort to prevent
varied between 1 (the target black diagonal bar), 5, biasingattentiontowardsthefaces.Participantscom-
15, and 30 items. The position of the black diagonal pleted20practicetrials.
bar varied between eight different positions of a E-prime software created a random order of trials
radius of 4in. from the black crosshair that remained per each participant so that no two participants saw
at the centre of the screen during the visual search the same presentation of trials. To avoid the same
paradigm. The black diagonal bar could appear at 0°, emotionshowingupseveraltimessuccessively,which
45°, 90°, 135°, 180°, 225°, 270°, and 315° along this could lead to habituation (Blau et al., 2007), the task
radius. Each visual search display was displayed twice cycled through each of the 6 priming conditions in a
for each of the 5 emotion conditions; one full set for random order, before repeating any of the 6 priming
COGNITIONANDEMOTION 7
6
1
0
2
y
a
M
0
2
3
4
7:
0
at
]
9
8
6.
7
1.
8
1
0.
5
[
y
b
d
e
d
a
o
nl
w
o
D
Figure2.(a)Aboveisanexampleofoneactress’emotions,aswellasthescrambledfacecontrol.(b)Visualsearchsetsizes.Thesearethe4set
sizeversionsofthevisualsearchforthetargetlocationof90°.(c)Visualsearchtrialprogression.
conditions. Within each priming condition, and within Order of presentation of the visual search arrays was
eachofthe4setsizes,the16faceswererandomlypre- completelyrandomisedwithineachprimingcondition.
sented before each visual search to insure the same The total time to complete the visual search task was
face did not show up more than once per set size. approximately20minutes.
For each of the 24 catch trials, one of the 16 faces ReactiontimedatawererecordedbyE-primesoft-
were randomly selected to prime each catch array. ware and measured the length of time from the
8 S.A.HAASETAL.
beginning of the visual search presentation until the disengagement (see Becker, 2009) we computed a
participant detected the target indicated by pressing LMM1. Our dependent measure was RT during set
thespacebar.Catchtrialsinwhichthere wasnoreal size 1, participant was our random effect, with
target and participants did not respond (after deter- emotion (surprised, angry, fear, happy, neutral,
mining the absence of the target) were used to scrambled)×Social Anxiety, and covariates State
verify participants’ attention and understanding of Anxiety and Sex as fixed effects. There were no main
the task. For catch trials, correct responses or omis- effects, or interactions, indicating that attention did
sions were scored with a 1 and errors were tagged not differ as a function of condition F(5, 87.06)=
with a 0 value. Participants who scored below 90% 1.12, p=.36, social anxiety F(1, 65.71)=.13, p=.73,
accuracy for catch trial response were excluded from state anxiety F(1, 65.71)=.77, p=.38, sex F(1, 65.58)
furtheranalyses(N=4,M=65%,SD=36%). =3.1, p=.08. The lack of reaction time differences
ReactiontimedataweresummarisedandmeanRT indicated that baseline reaction time did not differ
data (per emotion and set size) were calculated per asafunctionofSocialorStateAnxiety.Allfurtherana-
participant.Foreachparticipant’sdata,trialswithreac- lyseswereconductedontheslopeofeachindividual’s
tion times ±2 standard deviations from the partici- visualsearchfunction(Weierichetal.,2008).
pants’ mean reaction time were not included in
16 analysis of each participant’s RT. After removing Slope calculations
0
2 missed trials and outliers, the percentage of usable
y
a trials was calculated for each participant. Participants Asingleslopevaluewascalculatedperparticipantand
M
0 with less than 90% of usable trials were excluded per emotion priming condition. Slopes were calcu-
2 from further analysis. No further participants were lated as change in reaction time for target detection
3
4 excludedbasedonthesecriteria.Thefinalsampleana- as a function of change in number of items in each
7:
0 lysedconsistedof70ofthe74participantswhocom- of the set sizes. Each participant’s reaction time data
] at pleted the entire visual search task (MLSAS=53.39, for each emotion priming condition expression was
89 SD =29.07). fitted to linear slopes, using reaction time to detect
6. LSAS
7 the target during set size 1 as the intercept. The
81. average R2 value for visual search functions of the
1 Results
0. acrossthesamplewas(M=0.81,SD=0.09).
[5 Toconfirmthatthefoursetsizeconditionsweresuffi-
y
b cient to detect the effects of increasing demands
d Anxiety scaleand model selection
e selectivemeasuresofattention,asmeasuredbyreac-
d
oa tiontime(Treisman,1986),weranaLMMwithsetsize Totestwhetheremotionsdifferentiallyaffectedvisual
wnl type as a fixed-effect (no distractors, 4 distractors, 14 searchefficiency(slope)asafunctionofsocialanxiety,
Do distractors, 29 distractors) and participant as a aLMM1wascomputedusingslopeasthedependent
randomeffect1.ALMMapproachwasutilisedtoincor- measure,participantasarandomeffect,andemotion
porateindividualdifferencesandexperimentalmanip- (surprised, angry, fear, happy, neutral, scrambled)×
ulations into the analyses. A LMM is a more robust Social Anxiety2 and covariates State Anxiety and Sex
model compared to repeated-measures analyses of as fixed effects. The Scrambled Slope was the refer-
variance (rmANOVA), and among other advantages, ence or “baseline” condition in the model3. In the
accounts for random effects due to participants. For LMM, a reference for each categorical variable is uti-
in-depth explanation and application in visual atten- lised to examine differences between the reference
tion research, see Kliegl, Wei, Dambacher, Yan, and (one level of the categorical variable) and other
Zhou (2011), Kliegl, Masson, and Richter (2010), and levels of the categorical variable. In our particular
Mathôt, van der Linden, Grainger, and Vitu (2013). model, the selected reference condition was the
This analysis revealed the expected main effect of scrambled condition, so that our estimated fixed-
set size, F(3, 1035)=586.52, p<.001, with reaction effects were comparing each emotion condition to
times increasing with increasing number of the scrambled condition. As mentioned in the intro-
distractors. duction, we chose to use a scrambled face was used
Next, to determine whether the 600milliseconds as our reference condition/ baseline comparison
ITIbetweenthefaceprimeandthevisualsearchwas becauseascrambledfacestimulicontainsallthecom-
enough time to extinguish any residual effects of ponents of a face, however they do not allow the
COGNITIONANDEMOTION 9
6
1
0
2
y
a
M
0
2
3
4
7:
0
at
]
9
8
6.
7
1.
8
1
0.
[5 Figure3.Socialanxietymoderatestherelationsbetweenvisualsearchperformanceandtheeffectofemotionprimescomparedtoneutralor
y scrambledbaselines.
b
d
e
d participant to perceive an actual face or any type of State Anxiety increased, all emotion primes, neutral
a
nlo emotion, making it a potentially better comparison t(87.461)=−2.7, p<.01 d=−.57, happy t(105.41)=
w condition or baseline than the commonly used −1.80, p=.075, d=−.35, fear t(97.23)=−3.20, p<.01,
o
D neutral face. There was no main effect of LSAS score d=−.65, angry t(98.80)=−3.48, p<.001, d=−.70,
F(1, 65.387)=.84, p=.36, or State Anxiety F(1, 65.38) andsurprisedt(101.55)=−3.00,p<.01,d=−.59,facili-
=1.00, p=.32 and there were trend effects for sex tatedmore efficientvisualsearch comparedtobeing
F(1, 64.92)=3.83, p=.055, and emotion F(5, 90.79)= primed with ascrambled face. Importantly,estimates
1.88,p=.1. of fixed effects indicated that Social Anxiety, as
There were two significant two-way interactions: measured by LSAS score, moderated the impact of
Emotion by Social Anxiety F(5, 90.79)=2.61, p<.05, fear t(97.23)=2.69, p<.01, d=.55, angry t(98.80)=
and Emotion by State Anxiety F(5, 90.79)=3.13, 2.73, p<.01, d=.55, and surprised t(101.55)=2.71,
p <.05, Estimates of fixed-effects indicated that as p <.01 d=.54, primes on visual search (see Figure 3
Table3.LMMestimatesofEmotionxLSASscoreinteractionfixedeffects:scrambledconditionasreferencegroup.
Parameter Estimate Std.error df t Sig. Lower95%confidenceinterval Upper95%confidenceinterval
Surprised*LSASscore 0.022 0.008 101.55 2.71 0.008** 0.006 0.022
Angry*LSASscore 0.023 0.008 98.80 2.73 0.007** 0.006 0.023
Fearful*LSASscore 0.021 0.008 97.23 2.61 0.011** 0.005 0.021
Happy*LSASscore 0.013 0.009 105.41 1.49 0.139 −0.004 0.013
Neutral*LSASscore 0.008 0.008 87.46 0.98 0.33 −0.008 0.008
**p<.01.