Subliminal influencing in advertising: does it work?

Transcription

1 Subliminal influencing in advertising: does it work? Eva Van den Bussche & Gigliola Brintazzoli ULB /10/2013 Herhaling titel van presentatie 1

2 Overview Can subliminal information influence our behavior in an experimental context? (PART I) in a more real-life/advertising context? (PART II) Pag. 2

3 Part I Can subliminal information influence our behavior in an experimental context? Pag. 3

4 Early demonstrations Can subliminally presented information influence our behaviour? - Controversial - Long history - Subliminal = ideas below the limen or threshold for consciousness (Herbart, ) Pag. 4

5 Early demonstrations First empirical studies: Peirce & Jastrow (1884): Conclusion: even when Wich claiming Wich to be Pressure 1 Pressure 2 pressure pressure unaware of any difference was the (score=0), was the subjects could still strongest? discriminate strongest? the two pressures above chance level! 3 P1 P2 No preference, nonsensical answer See also Sidis (1898) forced-choice discrimination task Pag. 5

6 Masked priming paradigm Can subliminally presented information influence our behaviour? - Subliminal perception = a stimulus is demonstrated to be invisible while still influencing thoughts, feelings, actions, learning or memory (Kouider & Dehaene, 2007) - How do we measure subliminal perception today? Pag. 6

7 Masked priming paradigm Masked priming paradigm (Marcel, 1983) 9 17ms ## 33ms 6 480ms ## Smaller than 5 Larger than Pag. 7

8 Masked priming paradigm Congruent condition Incongruent condition Prime 6 1 Target 9 9 Difference (RT_I - RT_C) = priming effect Both > 5 One <, one > 5 Faster RTs Slower RTs Pag. 8

9 Masked priming paradigm Mid-1990s: methodological improvements (Dehaene, Greenwald) more reliable masked priming paradigms From then on: numerous experimental studies using the masked priming paradigm Van den Bussche et al. (2009): metaanalysis Pag. 9

10 Conclusion Part I Strong and robust subliminal priming effects across the experimental literature Subliminal information can influence our behavior in an experimental context! Pag. 10

11 Part II Can subliminal information influence our behavior in an real-life/advertising context? Pag. 11

12 Early demonstrations Vicary (1957): subliminal messages drink coca-cola, eat popcorn increased product sales Enormous impact on public opinion: Pag. 12

13 Early demonstrations Subliminal advertising was banned in many countries Vicary had falsified data Impact on public remained Subliminal advertising is still being used today McDonald s Pag. 13

14 People s perception Consumers: - are familiar with subliminal advertising (74-81%) - believe it is being used (68-81%) - believe it works (72%) Significant positive correlation with education Zanot et al., 1983; Synodinos, 1988; Rogers & Smith, Pag. 14

15 People s perception Questionnaire study (in prep): - Online (LimeSurvey) - Dutch, English and Italian version - General view on advertising - Definition of Unconscious influencing (UI) in advertising - Definition clear? - 3 questions assessing perception on UI in an advertising situation Pag. 15

16 People s perception Instructions Some people believe that advertisers intentionally place an unconscious message in their advertisements. These messages are hidden, which means that your visual system cannot consciously perceive them. These messages are designed to influence our behavior, for example to persuade us to buy a product, outside our awareness. An example of this is an experiment by Vicary in He showed people the messages Drink Coca Cola and Eat popcorn for a very short duration (a few milliseconds) during a movie. The movie-goers couldn t consciously perceive these messages. The question then is whether this kind of messages can influence our consumer behavior (in the example: will these messages lead to an increase in Coca Cola and popcorn sales?). An unconscious message is not something you don t pay attention to, but a message that you really can t see. In the following questionnaire we want to measure people's perception on this kind of unconscious influencing. We want to study whether you think this kind of unconscious influencing is present in advertising and whether you think these kinds of unconscious messages influence our behavior Pag. 16

17 People s perception N= % female Mean age = 43 (range 18-86) 84% Belgian 20.5% student 54% at least 1 child 40% married, 20% single, 16% cohabiting 25% master, 25% prof. bach., 22% secondary school, 15% academic bach. 62% owns house, 78% owns car Pag. 17

18 People s perception 1. Do you think UI is being used in advertising? 2. Do you think people in general are susceptible to UI in advertising? 3. Do you think you are susceptible to UI in advertising? Never _ Seldom _ Sometimes _ Often _ Always Pag. 18

19 People s perception Q1: used? Q2: people? Q3: you? 50 0 Never Seldom Sometimes Often Always Pag. 19

20 People s perception Participants believe that people in general are more susceptible to UI than they themselves (3.45 VS 2.86, t(637)=20.81, p<.001) Men VS women: men believe less that UI is being used (3.19 VS 3.37, p=.015), that people in general are susceptible to it (3.33 VS 3.50, p=.014) and especially that they themselves are susceptible to it (2.67 VS 2.96, p<.001) Pag. 20

21 People s perception Two-step cluster analysis: 3 clusters 4,5 4 3,5 3 2,5 2 Cluster 1 Cluster 2 Cluster 3 1,5 1 Q1: used? Q2: people? Q3: you? Pag. 21

22 People s perception Two-step cluster analysis: 3 clusters Cluster 1 (N=244): Strong believers Cluster 2 (N=324): Conservative group Cluster 3 (N=70): Skeptics What determines cluster membership? Pag. 22

23 People s perception Gender: Strong believers = 74% female, Conservative = 67% female, Skeptics = 47% female Other: skeptics are slightly younger than the other 2 groups, have a smaller weekly budget, are less likely to own a car/house, are more often single or cohabiting Pag. 23

24 People s perception Differences in general beliefs about advertising: Conservatives think less that they are exposed to advertising. They try to avoid advertising less (e.g., lower score on Switch channels during commercials ) Skeptics think less that they are influenced by advertising. They have a stronger sense of control (e.g., higher score on I know when an offer is "too good to be true ) and they are not afraid of advertising (e.g., lower score on Advertising should be more closely regulated ) Pag. 24

25 People s perception Strong believers think more that they are influenced by advertising. They are more suspicious about it (e.g., higher scores on Commercials try to make people buy things they don t really need ) No clear effects of personality traits, materialism, net income, being a student or not and educational level Pag. 25

26 People s perception Conclusion: People believe UI in advertising is being used and that it is effective More skeptic about their own susceptibility Men are more skeptic Different groups of people can be identified based on their beliefs about UI (Strong believers, Conservatives and Skeptics) Pag. 26

27 People s perception Actual application of unconscious advertising: - Rogers & Seiler (1994) questioned 256 American advertising companies about whether they had ever used UI - 91% NO, 8% did not understand the concept of UI correctly, only 1 firm had used it as a prank Pag. 27

28 People s perception Conclusion: People believe UI is being used and they believe it works BUT: companies are not using it Discrepancy between the perception of people and the actual use! Pag. 28

29 Time-course of subliminal priming Still the question remains: does it work? Generalizing findings made in an exp context to a more real-life situation is problematic time-course of subliminal priming Pag. 29

30 Time-course of subliminal priming Masked priming paradigm 9 33ms 17ms 6 ## SOA = 50ms 480ms ## Smaller than 5 Larger than Pag. 30

31 Time-course of subliminal priming Exp context: subliminal info (prime) and behavior undergoing the influence of it (response to target) follow each other very closely in time prime exerts its influence almost immediately Meta-analysis: average SOA = 128ms (max = 784ms) Pag. 31

32 Time-course of subliminal priming Subliminal priming is short-lived! Priming drops to a non-significant value within a few hundreds of milliseconds (Forster & Davis, 1984; Greenwald et al., 1996; Ferrand, 1996) Casts serious doubt on its effectiveness in everyday life and advertising Subliminal info (an ad) and the behavior undergoing the influence of this info (buying the product) are much farther apart Pag. 32

33 Time-course of subliminal priming Pratkanis, 1992 Trappey, Pag. 33

34 Subliminal priming applied Still, some studies have successfully applied subliminal priming in more real-life contexts Karremans et al. (2006): - Subliminally primed with Lipton Ice or Npeic Tol (23ms + masked) - Questions: - If you were offered a drink now, what would you prefer (Lipton Ice or Spa Rood) - If you would sit on a terrace now, how likely is it that you would order Lipton Ice/Coca Cola/Spa Rood (scale 1-7) - I would like to drink Lipton Ice/Coca Cola/Spa Rood at this moment (scale 1-7) Pag. 34

35 Subliminal priming applied Karremans et al. (2006): - Increased choice for, and intention to, drink Lipton Ice, but only for thirsty participants - See also Strahan et al., 2002; Bermeitinger et al., Pag. 35

36 Subliminal priming applied Consumer choices can be influenced by subliminal primes that could help fulfill a need, but only if the consumer is already deprived! - Veltkamp et al. (2011): even when no deprivation is present, subliminal conditioning can motivate consumers as if they were deprived - Verwijmeren et al. (2011): subliminally priming an habitual brand has no effect, and a primed brand can lead to increased choice even at the expense of an habitual brand Pag. 36

37 Subliminal priming applied Can we conclude that subliminal influencing in a real-life/advertising situation works? Let s not jump to conclusions just yet Methodological issues: - Time-course: prime and target still quite close in time, laboratory context - Prime awareness assessment Pag. 37

38 Prime awareness Prime awareness assessment: 1. Subjective threshold self-report (e.g.: Were you aware of the prime ) 2. Objective threshold discriminative abilities post-hoc post-test Identification: identify the prime Forced choice absent/present: was there a prime? Forced choice categorization: classify the prime Pag. 38

39 Prime awareness How fast will a method conclude that the primes were unconscious? 1. Subjective report (Post-hoc) 2. Prime identification 3. Forced choice absent/present, forced choice categorization Preferred! If a priming effect is observed AND the primes could not be perceived above chance, most strict evidence of truly unconscious/subliminal priming! Pag. 39

40 Our approach Aim: examine whether subliminal influencing can be effectively and reliably implemented in more everyday life and advertising situations, using strict methodology New studies: 1. Brintazzoli et al., 2012 (Con&Cog): real-life stimuli 2. Muscarella et al., (under revision): SOA Pag. 40

41 1. Brintazzoli et al., 2012 Idea = back to basics! Design an experiment very similar to a typical masked priming study BUT: with more real-life stimulus material Pag. 41

42 1. Brintazzoli et al., 2012 Stimuli Typical masked priming experiment Primes = 10 very familiar brand logos selected in a pilot study Targets = letter strings Task: decide as fast as possible whether the target is a word (or brand name) or a nonsensical non-word 2 versions: conscious (17ms) or unconscious (13ms) Pag. 42

43 1. Brintazzoli et al., conditions a) related brand: - MCDONALD S b) unrelated brand: - LACOSTE c) related non-brand: - HAMBURGER d) unrelated non-brand: - CAR e) non-word: - NOOLWEF 400 trials (50% word and 50% non-word) Only 200 word trials were analyzed Pag. 43

44 Design: Pag.44

45 1. Brintazzoli et al., 2012 Prime visibility Objective forced choice categorization test Conscious version (N=39): - Subjects correctly categorized 75% of the primes - d =1.56, t(38)= 9.43, p<.001 Unconscious version (N=32): - Subjects correctly categorized 54% of the primes - d = 0.29, t(31)= 3.91, p<.001, no correlation with priming, no differences between highest and lowest d group Pag. 45

46 1. Brintazzoli et al., 2012 Results ** 530 RT (ms) ** related unrelated brand non-brand brand non-brand conscious unconscious Pag. 46

47 1. Brintazzoli et al., 2012 Discussion Brand logos possess the power to prime their brand names and, remarkably, words associated to the brand primes McDonald's, but also hamburger! However, this only occurred when they were presented above the consciousness threshold! Pag. 47

48 2. Muscarella et al., under rev. BUT At prime level: 5 of the 10 primes DID trigger priming in the brand and nonbrand condition! New study with only these 5 logos Pag. 48

49 2. Muscarella et al., under rev. Aim: Study more long-term effects of these logos on behavior E.g., Capa et al. (2011): long-term effects of goal-related words, but only when primes had been directly associated with visible positive words acting as a reward Manipulation of SOA: 334, 1000 or 5000ms (separate blocks) Pag. 49

50 2. Muscarella et al., under rev. Stimuli: only 5 logos Design = very similar Pag. 50

51 2. Muscarella et al., under rev. Prime visibility Objective forced choice categorization test Conscious version (N=28): - Subjects correctly categorized 94% of the primes - d =3.25, t(27)= 20.08, p<.001 Unconscious version (N=24): - Subjects correctly categorized 54% of the primes - d = 0.22, t(23)= 1.79, p=.087, no correlation with priming Pag. 51

52 2. Muscarella et al., under rev Results ** ** ns *** *** ** ** ns *** *** ** ns related unrelated SOA 334 SOA 1000 SOA 5000 SOA 334 SOA 1000 SOA 5000 SOA 334 SOA 1000 SOA 5000 SOA 334 SOA 1000 SOA Pag. 52 brand non-brand brand non-brand conscious unconscious

53 2. Muscarella et al., under rev. Discussion primes McDonald's, even when presented unconsciously and when 5s pass between prime and target primes Hamburger, even when presented unconsciously, but this spreading of activation to semantically related words is limited to shorter prime-target intervals, especially for unconscious primes Pag. 53

54 2. Muscarella et al., under rev. Discussion Unconscious information can exert its influence on our behavior for at least 5 seconds after its presentation. However, the semantic network triggered by the information seems to decay rapidly over time Pag. 54

55 Conclusion Part II Unconscious real-life stimuli can elicit shortand long-term priming effects Necessity of a strict prime awareness assessment Quality of the primes = crucial However: still artificial/experimental setting, effects on low-level behavioral tasks Future studies: focus on decision-making, choice behavior Pag. 55

56 Conclusion Can subliminal information influence our behavior in an experimental context? YES! in a more real-life/advertising context? Could be??? Pag. 56

57 Contact Eva Van den Bussche Vrije Universiteit Brussel Department of Psychology Pleinlaan Brussels Belgium Eva.Van.den.Bussche@vub.ac.be SCAN Utrecht Pag. 57