The AB paradigm taps into the sequence of processes occurring immediately after the perception of target stimuli appearing in close temporal adjacency. Said differently, this particular effect spreads out the competition between the processes evaluating incoming target stimuli: Each point of the AB curve (Figure 2.1, panel b) thus reflects the result of the competition between the processes evaluating both the first and second targets. By setting the emphasis on the temporal dimension of the processing, this paradigm renders it possible to address the sequence of events responsible for the report of targets. It is especially interesting for emotion research, as it allows once to probe the processing priority that seem to benefit emotion-laden stimuli throughout the various stages of processing (Vuilleumier, 2005).
Emotion researchers using this paradigm typically compare an AB response obtained with emo-tional material to a control condition reflecting a “normal” AB response with neutral material.
Varying the onset time of the second target relative to the first target allows to probe 1) the
the first target (i.e., the likelihood of preventing the second target to be reported), and 3) the processing priority of the second target (i.e., the likelihood for the second target to be reported, as well as the likelihood of disturbing the processing of the first target). Researchers will thus seek to control one of such aspects to manipulate and investigate the others.
Not surprisingly, a number of neuroimaging studies in human and non-human primates have demonstrated activation of emotion-laden brain areas, like the amygdala and parahippocampic areas (Marois et al., 2004; Kranczioch et al., 2005; Johnston et al., 2007), the locus coeruleus (Nieuwenhuis, Gilzenrat, et al., 2005; Nieuwenhuis, Aston-Jones, & Cohen, 2005), or cingulate cortices (Marois et al., 2004; Gross et al., 2004; Feinstein et al., 2004; Kranczioch et al., 2005;
Johnston et al., 2007). These particular brain areas may produce biasing signals that may support the processing of emotional signals, and explain why unreported targets (missed T2) still seem to be processed to an extended level, supporting some priming effect on a subsequent task (e.g. Luck et al., 1996; Marois et al., 2004).
What is the effect of an emotional T2? By far, the most common situation is to present participants with a neutral stimulus as T1 and an emotional stimulus as T2, addressing the extent to which emotional stimuli can defeat the “blink” mechanism triggered by the perception of T1 (see Table 2.2). In this context, researchers hypothesise that emotional material is less dependent on attentional resources to achieve awareness, and is thus more likely to reach the stages of processing required for conscious awareness and report (Anderson & Phelps, 2001; E. Fox et al., 2005). Using this variation of the paradigm, the AB has been shown to be alleviated by personal names (i.e.
compared to names of other people; Shapiro, Caldwell, & Sorensen, 1997), primed words (Maki et al., 1997; Nieuwenstein et al., 2005; Nieuwenstein, 2006), negative words (Anderson & Phelps, 2001;
Kihara & Osaka, 2008), and otherwise neutral pictures conditioned to white noise (S. D. Smith et al., 2006). Similarly, the AB is alleviated by happy schematic faces (Mack et al., 2002), distinctive (Ryu & Chaudhuri, 2007) or familiar faces (Jackson & Raymond, 2006; Gomez-Cuerva et al., 2008). Several studies however tend to show that the arousal elicited by emotional words has stronger of an effect on the AB than their valence (Anderson, 2005; Keil & Ihssen, 2004; Keil et al., 2006). As one could expect, the magnitude of the blink has been shown to correlate negatively with trait anxiety for fearful (E. Fox et al., 2005) and angry faces (Jong & Martens, 2007), and the same pattern of results is demonstrated for spider phobics presented with spider-related stimuli (Reinecke et al., 2007) – the more pronounced the disorder the less AB.
PublicationTypeofT1(Task)TypeofT2(Task)Dur.(ISI) inmsPart.ResultsLag-1 Shapiroetal.(1997) –Experiment1Nouns(ID)Ownname,othername,noun(DE)60(15)N=3x9Ownname>Othername>>Nounyes –Experiment2Nouns(ID)Ownname,othername,noun(DE)60(15)N=3x9Ownname>>Othername=Nounyes –Experiment3Nouns(ID)Ownname,othername(DE)60(15)N=9SmallAB;Ownname=Othernameyes –Experiment4Nouns(ID)Ownname,noun(DE)60(15)N=9SmallAB;Ownname=Othernameno Makietal.(1997)–manipulatedsemanticrelationsbetweenT1,T2anddistractors Experiments1–5Nouns(ID)Nouns(ID)≈85(≈15)N=≈64LessABwhenT1andT2relatedn/a Andersonetal.(2001)Nouns(ID)Nouns(ID):NegvsNeu130(0)BiAmyg+ RTL/LTLNeg>>Neu(exceptBiAmyg+LTL)n/a Macketal.(2003)Miscobjects(ID)HFI,HFIinverse,trees(DE)75(0)N=42HFI>>HFI>Treeyes Keiletal.(2004) –Experiment1Verbs(ID)HAverbs(ID):PosvsNegvsNeu116(19)N=19Neg>Pos>>Neuno –Experiment2Verbs(ID)LAverbs(ID):PosvsNegvsNeu116(19)N=19Neg=Pos>>Neuno –Experiment3Verbs(ID)HAverbs(ID):PosvsNegvsNeu116(19)N=19Neg>Pos>>Neuno Anderson(2005) –Experiment1Nouns(ID)Nouns(ID):NegvsTaboovsNeu100(0)N=2x20Taboo>>Neg>Neuno –Experiment2Nouns(ID)Posnouns(ID):HAvsLAvsNeu100(0)N=2x16HA>LA>Neuno –Experiment3aNouns(ID)Nouns(ID);HAvsNeuvsNeu∼HA100(0)N=2x22HA>>Neu=Neu∼spellingHAyes –Experiment3bNumerical(ID)Nouns(ID):HAvsUnusualNeu100(0)N=17HA>>unusualNeuyes –Experiment3cNumerical(ID)Nouns(ID):HAvsUnusualNeu100(0)N=20UnusualNeu>>HAno –Experiment4aNouns(ID)Nouns(ID):HAvsNeu100(0)N=20HA>>Neuno –Experiment4bXorO(IDs)Nouns(ID):HAvsNeu100(0)N=20HA>>Neu;HAlessaffectinRTno Foxetal.(2005)MushroomsvsFlowers(ID)Faces:FearfulvsHappy110(0)ADN=14H +14L
HAnx:Fearful>>Happy;LAnx: Fearful=Happyn/a Nieuwensteinetal.(2005) –Experiment1Digits(ID),cueDigits(ID)33(50)N=18T2-2>>T2-1=T2=uncuedn/a –Experiment2Digits(ID),cueDigits(ID),T2-2:SameorDifferent33(50)N=18Same>>Different>uncuedn/a –Experiment3Digits(ID),cueDigits(ID),T2-2:SameorDifferent33(50)N=20Singletask>>Dualtaskn/a Jacksonetal.(2006) –Experiment1CirclesvsSquares(ID)Unfamiliarfaces(DE)85(0)N=26AB(withditractors:unfamiliarfaces)no Continuedonnextpage
PublicationTypeofT1(Task)TypeofT2(Task)Dur.(ISI) inmsPart.ResultsLag-1 –Experiment2CirclesvsSquares(ID)Famousfaces(DE)85(0)GBN=16vs OEN=12GB>OE(1lag)no –Experiment3CirclesvsSquares(ID)Unfamiliarfaces(DE)85(0)GBN=43AB(withdistractors:famousfaces)yes Keiletal.(2006)Verbs(ID)HAVerbs;PosvsNegvsNeu116(0)N=13Neg>Pos>Neun/a Reineckeetal.(2007) –Experiment1Householditems(ID)Neu(mushrooms)vsPos(blossom)vs Neg(Spiders)(ID)80(80)N=60Neg>>Pos>Neuyes –Experiment2Householditems(ID)Neu(mushrooms)vsPos(blossom)vs Neg(Spiders+Snakes)(ID)80(80)SPhN=31H +36LNeg>Pos>Neu;nogroupdifferenceyes Ryuetal.(2007)–#2Houses(ID)Neuface(averagevsdistinctive)(DE)100(0)N=37Distinctive>Averageno Einh¨auseretal.(2007)Neutralfaces,Watches(ID)Neutralmiscpictures6-40HzN=6Faces>Watches;DurationofABis category-dependent
yes (faces) DeMartinoetal.(2008)–Pharmacologicalstudyinvestigatingadrenergicsystem –Experiment1Nouns(ID)Nouns(ID):ArovsNeu130(0)N=2x36Emo>>Neu,andno –Experiment2Nouns(ID)Nouns(ID):ArovsNeu110(0)N=3x10β-blockadereducesperformance,andno –Experiment3Nouns(ID)Nouns(ID):ArovsNeu110(0)N=3x10especiallyforemotion-ladenstimulino DeJongetal.(2007)Happy,Angryfaces(ID)Happy,Angryfaces(ID)120(0)SADN= 16H+17L
T1Angry:nochangeAB;T2Angry alleviatesAB;nogroupdiff.n/a Thompsonetal.(2007)Digits(ID)Vowels(ID)100(0)N=60Non-primed>Primed(300ms)no Trippeetal.(2007)IAPSNeuIAPSNegvsNeu(Distractors: Spiders,etc)144(0)SPhN=14 vsN=16
Controls=Patients(Emo>>Neu); Patients(Spiders>>Others)n/a Kiharaetal.(2008) –Experiment1Kanji:Neu(ID)Kanji:PosvsNeu;NegvsNeu(ID)100(0)N=2x18Neg>>Neu;Pos=Neuno –Experiment2Kanji:Neu,HighNeg,Low Neg(ID)Kanji:Neu(ID)100(0)N=14NegT1createsABno –Experiment3Kanji:Neu,Neg(ID)Kanji:NegvsNeu(ID)100(0)N=16Lag1:Neu>Neg;Lag3:Neg>Neu; Lag7:Neu=Negyes DeMartinoetal.(2008)Misclandscape(ID)Faces:FeavsNeu70(0)N=15Fea>>Neun/a Maratosetal.(2008)Schematicfaces:Neu(ID)Schematicfaces:HapvsAngvsNeu128.5(0)N=23Angry>Happy>Neutralno Continuedonnextpage
PublicationTypeofT1(Task)TypeofT2(Task)Dur.(ISI) inmsPart.ResultsLag-1 Gomez-Cuervaetal. (2008)CirclesvsSquares(ID)Faces:FeavsHapvsAng85(0)undisclosedABforallemotion;LongSOA:Happy >>Angry/Fearfuln/a Giesbrechtetal.(2008)(in –Experiment1R/LArrows,flanked(ID)Ownname,Othername(GD)53.3(53.3)N=24ABtoownnameisload-dependentno200–800 –Experiment21digitvs2digits(PA)Ownname,Othername(GD)53.3(53.3)N=16ABtoownnameisload-dependentno200–800 –Experiment31digitvs2digits(PA)Ownname,Othername(GD)53.3(53.3)N=15Noeffectofload;Own>Otherno Roeschetal.(2009) –Experiment1Faces:Neu(GD)Faces:ModexEmotion(DE)80(0)N=37Mode:Dyn>>Stat;Emotion:shorter lag-1sparingyes –Experiment2Faces:Neu(GD)Faces:StaticFeavsDynFeavsDyn scrambled60(0)N=14StatifFear=DynFea>>Dyn Scrambledn/a 480 Raymondetal.(2009)CirclesvsSquares(ID)FacesNeu($)85(80)N=24RewardedfacesdecreasedABn/a 800 Table2.2:EmotionandtheABintheliterature–Studiesthathaveinvestigatedtheimpact ofemotionalT2.Ang:Angry;BiAmyg:bilateralamygdalalesion;DE:Detect;E/L:Earlyvs Late;GB/OE:British/OtherEuropean;GD:Genderdecision;Fea:Fearful;H/L:High/Low; HA:Higharousal;Hap:Happy;HFI:HappyFaceIcon;ID/IDs:Identify/speeded;n/a:not applicable;Neg:Negative;Neu:Neutral;PA:Paritydecision;Pos:Positive;RTL/LTL: Right/LeftTemporallobelesion;RT:Reactiontime;SPh:Spiderphobics.(Originalwork elaboratedinthecourseofthisthesis.)
stimulus as T1, and a neutral stimulus as T2 to address the extent to which the processing of emotional material prevents subsequent stimuli from entering the stages required for report (see Table 2.3). In other words, researchers hypothesise that, compared to neutral targets, the processing of emotional targets will occupy and hold attention for a longer period of time, causing a stronger AB on subsequent targets. Fewer studies have addressed this phenomena but, in general, results confirm this hypothesis: showing such an effect when participants are asked to identify negative words (compared to positive and neutral words; Vaquero et al., 2006), emotional faces (Jong & Martens, 2007), and arousing/taboo words (Arnell et al., 2007; Mathewson et al., 2008;
Kihara & Osaka, 2008) or arousing pictures (Most et al., 2007), or even when they do not need to perform any task and the emotional material is seen as a simple distractor (Barnard et al., 2004;
Huang et al., 2008; Giesbrecht et al., 2008).
PublicationTypeofT1(Task)TypeofT2(Task)Dur.(ISI) inmsPart.ResultsLag-1 Barnardetal.(2004)Nouns(ID):human-,household-, nature-relatedJob(DE)110(0)N=30SemanticallyrelatedT1createsAByes Vaqueroetal.(2006)Nouns(ID):PosvsNegvsNeu“AGUA”(DE)41(0)N=36NegT1createsAByes Smithetal.(2006)BirdsvsCars(Notask)conditioned vslandscapesRotatedlandscapesvsbuildings100(16)N=16ConditionedT1increasesABn/a DeJongetal.(2007)Happy,Angryfaces(ID)Happy,Angryfaces(ID)120(0)SADN= 16H+17L
T1Angry:nochangeAB;T2Angry alleviatesAB;nogroupdiff.n/a Arnelletal.(2007)–notaskonT1 –Experiment1Nouns:NeuvsPosvsNegvsHAColourname(ID)110(0)N=18HAcreatesAByes –Experiment2Nouns:NeuvsPosvsNeg(Sad)vs HAColourname(ID)110(0)N=24Lag3:HAcreatesABn/a –Experiment3Nouns:musicvssexualtabooColourname(ID)110(0)N=43Lag3:SexualtaboocreatesABn/a Mostetal.(2007)–notaskonT1 –Experiment1♀nudevs♀/♂clothedRotatedlandscapes,buildings(ID)106(0)♂N=20Lag2:nudecreatesABn/a –Experiment2Eroticcouplesvs♀nudevsNeuRotatedlandscapes,buildings(ID)111(0)♀N=16($)Lag2:nudecreatesABdespiterewardn/a –Experiment3EroticcouplesvsgorevsNeuRotatedlandscapes,buildings(ID)106(0)♂N=15vs ♀N=8
Gore+nudecreateAB;primingofT2 alleviatesABn/a Mathewsonetal.(2008) –Experiment1Nouns(ID):NeuvsNegvsPosvs TabooNouns(ID)117(0)N=24TaboocreatesABeveninsingle-task conditionyes –Experiment2Nouns(ID):NeuvsNegvsPosvs TabooNouns(ID)117(0)N=78TaboocreatesABeveninsingle-task conditionyes Kiharaetal.(2008) –Experiment1Kanji:Neu(ID)Kanji:PosvsNeu;NegvsNeu (ID)100(0)N=2x18Neg>>Neu;Pos=Neuno –Experiment2Kanji:Neu,HighNeg,LowNeg (ID)Kanji:Neu(ID)100(0)N=14NegT1createsABno –Experiment3Kanji:Neu,Neg(ID)Kanji:NegvsNeu(ID)100(0)N=16Lag1:Neu>Neg;Lag3:Neg>Neu; Lag7:Neu=Negyes Continuedonnextpage
PublicationTypeofT1(Task)TypeofT2(Task)Dur.(ISI) inmsPart.ResultsLag-1Lags Huangetal.(2008)–notaskonT1 –Experiment1Nouns:NegvsNeuFruitnames(ID)75(0)N=16NegcreatesmoreABthanNeuyes1, –Experiment2Nouns:NegvsNeuFruitnames(ID)incapitalletters75(0)N=16Neg=Neuyes1, –Experiment3Nouns:NegvsNeuRhymingwords(ID)75(0)N=16Neg=Neuyes1, –Experiment4(notanABexperiment) –Experiment5Nouns:NegvsNeuFruitnamesorcapitalwords(ID)75(0)N=32Effectofemotiononlyforlag3in semantictaskyes1, Table2.3:EmotionandtheABintheliterature–Studiesthathaveinvestigatedtheimpact ofemotionalT1.Seetable2.2forlegend.(Originalworkelaboratedinthecourseofthis thesis.)
2.4 Conclusion
In this chapter, we quickly reviewed some fundamental aspects covering the link between emotion and attention. In particular, an impressive variety of data suggests that emotion influences at-tention in several ways: emotion-laden material modulates spatial atat-tention, enhances perception and takes precedence over concurrent information. However, the various paradigms from which this coherent picture emerges seem to be very sensitive, and under certain conditions provide rad-ically different results. New apertures are being developed in the form of experimental paradigms that specifically target the unfolding of the processing. In the AB for instance, a second target is used to probe the general availability of the processing system as it is currently processing a first target. A typical response shows that after a short period of time during which both targets can be processed together (“Lag-1 sparing”), the performance drops dramatically (for a peak at about 300 msec after T1) before recovering slowly.
Emotion researchers have used this paradigm to assess the extent to which the processing system is tuned in favour of emotion-laden material. Results generally demonstrate that emotional stimuli benefit from biases throughout the many stages of processing, and that upon ignition of this processing, the cognitive system becomes less susceptible to interference and supports emotion-laden information. However, even though the AB could, in theory, provide valuable information about the stream of processing, the coarse picture depicted so far by these studies does not allow for the precise description of the sequence of cognitive processes underlying the orienting of attention to emotional material.
One reason for this may be the heterogeneity with which researchers implement this experimental paradigm. In this paradigm, which focuses on the temporal aspect of the processing, it is to be expected that different temporal parameters (e.g., durations, ISI) will affect the results. For instance, one trial, containing about 20 stimuli rapidly flickering on the screen (distractors and two targets), may yield different perception depending on the rate of stimulation. The dispute between Hommel & Akyurek (2005) and Dehaene et al. (2003), for instance, each side claiming that conscious recognition of targets is signed by the cortical activity within a particular frequency band, may be resolved by considering differences in temporal parameters yielding different stimulation rate (see Einhauser et al., 2007; Vul, Hanus, & Kanwisher, 2008, for experiments with different presentation rate).
Another reason may be the lack of an efficient methodology to assess the results obtained with this paradigm. If the AB makes it “easy” to probe the state of the processing system, and its readiness
to emotional interference at a given moment of the processing, there is no straightforward way to measure and characterise the stages of processing being probed. A possible way to answer to this critic may be through the use of tailored statistical analyses (Cousineau et al., 2006), as we used in this work and will present in the next chapters.
Statement of objectives
What drives the orienting of attention to emotion-laden stimuli and how?
With a view to addressing these questions, we used current emotion theories to guide an inves-tigation of the sequence of cognitive processes yielding the orienting of attention to emotional objects in the environment. In Chapter 1, we introduced three of the main theoretical tradi-tions of emotion: dimensional theories, basic emotion theories and appraisal theories of emotradi-tions.
In Chapter 2, we reviewed some of the methodologies used to investigate emotional attention, and identified temporal attention as an ideal framework to shape our efforts. In this chapter, we will contrast the predictions from the three theoretical traditions, and formulate the working hypotheses that served as foundation to our work.