The Implicit-Affect-Primes-Effort Model

As demonstrated in several studies, affective states influence effort mobilization (e.g., Brinkmann & Gendolla, 2007, 2008; Silvestrini & Gendolla, 2009a, 2009b). Based on the Mood-Behavior-Model (Gendolla, 2000), moods influenced the subjective evaluation of task difficulty. Gendolla, and Krüsken (2001) demonstrated that after music presentation manipulating mood states, participants modulated their effort mobilization during subsequent task performance. The authors reported that in an easy task context, sad mood led to higher effort-related cardiovascular response than happy mood. By contrast, in a difficult task context, the authors observed the opposite pattern: higher

33 effort-related cardiovascular response in a happy mood than in a sad mood. However, these effects were demonstrated with conscious moods.

As reported above, implicit affect primes can influence judgments and behavior.

Recent research showed that implicit affect primes, by activation of emotion concepts in memory, also influence evaluative judgments (see Niedenthal, 2008). Based on these results, implicit affect primes could have the same effect on effort as conscious moods. In this sense, implicit affect primes should influence effort mobilization by their impact on subjective task demand.

Figure 2. The basic assumptions of the IAPE model about a link between affect primes (sadness, fear, happiness, and anger), activated knowledge about ease or difficulty, experienced task demand, and effort mobilization as long as success is possible and justified (Figure from Gendolla, 2012, facial pictures from the AKDF- Lundqvist, and Litton, 1998).

34 The Implicit-Affect-Primes-Effort model (IAPE, Gendolla, 2012) posits that implicit affect primes influence evaluative judgments and behavior by activating emotion knowledge. The primes’ influence depends on the accessibility and applicability of mental representations according to general principles of knowledge activation, i.e., priming-effects on judgment and behavior (see Förster & Liberman, 2007).

The IAPE model explains the influence of implicit affect on effort mobilization in active coping. According to motivational intensity theory (Brehm, and Self, 1989), effort is mobilized proportionally to the level of subjective task demand as long as success is possible and justified (Brehm & Self, 1989; Wright & Kirby, 2001). The IAPE model suggests that effort, respecting the resource conservation principle, will be mobilized in dependence on the evaluation of available information concerning task difficulty. Implicit affect stimuli will influence the subjective evaluation of task demand according to accessible information about performance ease or difficulty, which is typical for the respective emotion accessible. As depicted in Figure 2, happiness and anger stimuli are associated with ease. Consequently, subjective demand will be low. By contrast, sadness and fear stimuli are associated with difficulty and will increase subjective task demand.

As subjective task demand influences effort mobilization, implicit sadness and fear cues will lead to higher effort intensity than implicit happy and anger cues, as long as success is possible and justified.

Studies from our laboratory testing of the IAPE model used the same procedure (Gendolla, & Silvestrini, 2011; Lasauskaite et al., 2012; Silvestrini & Gendolla, 2011a, 2011b, 2011c). First, the authors assessed biographical data and self-report measures of participants’ feeling state before exposure to the affect primes. Next, the protocol started with a habituation period (8 min) assessing cardiovascular baseline values at the rest.

During this period, participants watched a hedonically neutral video. Then participants received task instructions and performed training trials followed by the task. Usually, participants performed a mental concentration (Brickenkamp, 1981) or a short term memory task (Sternberg, 1966).

To test the influence of implicit affect on effort-related cardiac response, briefly flashed and backward-masked pictures of emotional expressions were integrated into the task. Each trial started with a fixation cross at the center of the screen (1000 ms) followed by a flashed facial expression (26 ms) directly followed by a backward mask (133 ms).

To avoid fast adaptation to the emotional expression, only 1/3 of the trials presented an

35 emotional expression, while 2/3 presented neutral expressions. Then, the item of the cognitive task appeared followed by the message “response entered” presented for 3 sec.

minus participants’ reaction time in order to keep the task duration identical for each participant. To prevent affective reactions that could interfere with the affect primes’

impact (e.g., Kreibig, Gendolla, & Scherer, 2010), we gave no feedback in the experimental trials.

After the task, participants retrospectively rated subjective demand and the same affect items that had been assessed at the beginning of the experiment to assess possible affect prime effects on conscious feelings. To finish, the efficiency of the implicit priming procedure was assessed with prime recognition test or a funnel debriefing procedure (Bargh & Chartand, 1996).

To summarize, there is no doubt that affective states influence human behavior.

Numerous studies have demonstrated the impact of emotions on judgment and behavior.

Moreover, Gendolla’s (2012) IAPE model explains the influence of implicit affect on effort mobilization. Nevertheless, the majority of studies presented refer to the impact of positive or negative affects, especially happiness and sadness (Silvestrini & Gendolla, 2011c). The IAPE model suggests that implicit anger primes influence effort mobilization similarly as happiness stimuli. However, despite the specificity of anger, the influence of implicit anger on effort mobilization is still under investigated. In a recent study, Gendolla and Silvestrini (2011) found that implicit anger faces lead to lower effort intensity than implicit sadness faces in a “do your best” task context. These results demonstrated, for the first time, the influence of implicit anger primes on effort intensity in active coping context. Nevertheless, investigations on the impact of implicit anger stimuli still uncompleted.

36 I.5. Anger: A Particular Affect

The aim of this thesis is to test the IAPE model predictions’ concerning the influence of implicit anger on effort mobilization. After discussion of relevant anger characteristics, this fifth part of the present introduction will outline general predictions guiding the studies conducted in this thesis.

I.5.1. Definition

“Anger is a negatively valenced emotion characterized by high arousal” (Kuppens, 2008). Anger has been characterized as one of the basic emotions described by Ekman and Friesen (1975) and Plutchik (1980). Moreover, anger serves a variety of adaptive functions in self-defense (Izard & Kobak, 1991; Lemeris & Dodge, 2008; Lewis et al., 1992). Appraisal theories of emotions (e.g., Scherer, Schorr, & Johnstone, 2001) suggest that anger is elicited by the appraisal of an event as relevant, important for the self, but incongruent with the personal’s motives and well-being (Kuppens, 2008). Theoretically, anger stimuli induce threat and avoidance. Accordingly, it has been posited that anger stimuli should induce feelings of fear (Berkovitz & Harmon-Jones, 2004a, 2004b).

Nevertheless, based on Fridja’s works about action tendencies (1986, 2007), fear predisposes avoidance. By contrast, anger itself motivates attack, i.e., behavioral approach. Moreover, from a functionalist perspective, anger’s function is to overcome potential obstacles in goal pursuit (Saarni et al., 2006).

I.5.2. The Particularity of Anger

Although anger is classified as a negative affect, numerous studies suggest that anger stimuli lead to behavioral responses that are similar to those of happiness stimuli.

From a neuroscientific point of view, it has been shown that anger stimuli activate the left prefrontal cortex (Jones, 2003a; Jones & Allen, 1998; Harmon-Jones et al., 2003; van Honk & Schutter, 2006; Wacker, Heldmann, &, Stemmler, 2003).

These studies have demonstrated that anger stimuli lead to similar neural activations as positive affective stimuli, illustrating the special status of anger in comparison with others negative affects, which activate the right prefrontal cortical region.

37 Moreover, recent studies have demonstrated that anger is associated with activation of the Behavioral Approach System (BAS) (Caver & Harmon-Jones, 2009;

Harmon-Jones, 2003b; Harmon-Jones & Allen, 1998; Harmon-Jones et al., 2009).

According to the BIS (Behavioral Inhibition System) / BAS (Behavioral Approach System) model (Gray, 1982; Carver & White, 1994), positive affect is associated with approach behavior and negative affect is associated with inhibition. Most relevant, Lerner and Keltner (2001) demonstrated that angry individuals were highly optimistic and also felt they had high control over the situation. For achievement contexts, this last study suggests that a high level of control leads one to consider a task as easier. It follows that anger should reduce the subjective demand during performance (Wright & Dismukes, 1995).

Moreover, based on the systematic impact of affect stimuli on human behavior, numerous studies showed that anger stimuli systematically influence evaluative judgments (Adams, 2006; Smits & Kuppens, 2005), behavior (Wacker, et al., 2003), and attention (van Honk, et al., 2001). Van Honk and colleagues (2001) demonstrated an attentional bias for masked angry faces showing a facilitating effect of implicit anger stimuli on attention.. According to recent findings suggesting that anger is associated with ease, Putman and colleagues found that implicit anger stimuli have a facilitating effect on emotional Stroop performance (Putman, Hermans, & van Honk, 2004).

I.5.3. Implicit Anger and Effort Mobilization: Predictions

Results from the studies cited above suggest that exposure to anger primes can activate emotion knowledge about performance ease. Gendolla and Silvestrini (2011) confirmed this by showing that masked anger stimuli presented during cognitive tasks influence effort intensity. Anger and happiness primes led to lower effort than sadness primes in a “do your best” task context.

To summarize, despite clear evidence for the similarities between the effects of anger and positive affect on behavior, studies investigating the impact of implicit anger stimuli on effort mobilization during cognitive tasks are still rare.

38 Nevertheless, according to studies showing that anger stimuli share numerous motivational similarities with happiness stimuli, we can posit, according to the IAPE model (Gendolla, 2012) and Gendolla and Silvestrini’ (2011) results that implicit anger stimuli will influence effort mobilization similarly as happiness primes. Anger stimuli activate the anger emotion concept that is linked with ease, leading to reduce task demand.

39 I.6. This Present Thesis

This thesis investigates the impact of implicit affect on the intensity aspect of motivation. More specifically, this thesis aims to provide evidence for the moderating impact of implicit anger stimuli on effort intensity during cognitive tasks.

I.6.1. Objectives

Based on the IAPE model (Gendolla, 2012), implicit affective stimuli influence subjective task demand, which in turn influences effort mobilization in cognitive tasks.

Indeed, anger shares numerous motivational properties with positive affects in motivation (Harmon-Jones, 2003b). Moreover, recent studies showed a systematic influence of implicit affect primes on subjective task difficulty and effort (Gendolla & Silvestrini, 2011; Lasauskaite et al., 2012; Silvestrini & Gendolla, 2011b, 2011c). Most relevant, Silvestrini and Gendolla (2011) found that implicit anger stimuli led to lower subjective task demand than implicit sadness primes, demonstrating for the first time the moderating effect of implicit anger during task performance. This study demonstrated the facilitating effect of implicit anger stimuli on effort mobilization, but it also invite interrogations concerning the facilitating effect of implicit anger stimuli and the joint impact of task difficulty and monetary incentive on effort intensity, which will be investigated in the experimental part of this thesis.

I.6.2. Predictions

Using cardiovascular indices, and more specifically PEP as quantitative indicator of effort intensity (Kelsey, 2012), this thesis investigates the impact of implicit anger on effort-related cardiac response. Based on previous work showing that implicit affect primes can activate emotional knowledge influencing the experience of task demand, we predict that implicit anger should have a similar influence as implicit happiness on effort-related cardiac response: Implicit anger should be associated with the experience of performance ease.

Experimental Part

43

II. Experimental Part

II.1. Overview of the Studies

With the series of studies realized for this thesis, we tested the specificity of anger prime impact on effort-related cardiovascular response, compared to masked sadness stimuli. Moreover, we aimed to test the moderating effect of anger. First, we aimed to demonstrate that masked anger stimuli lead to lower effort intensity than masked neutral stimuli. Secondly, we investigated the moderating effect of implicit anger stimuli on effort intensity manipulating task difficulty and monetary incentive.

In the first two studies we tried to extend results by Gendolla and Silvestrini (2011). In order to provide evidence for the facilitating impact of masked anger stimuli on effort-related cardiac response. In this vein, we added a control condition using neutral facial expressions. Results found further support for a facilitating effect of implicit anger stimuli.

With the third study, we investigated the joint effect of implicit affect primes and objective task difficulty on effort mobilization. We compared masked anger stimuli in comparison with another negative affect (sadness). As predicted, results showed a significant interaction effect between implicit affect primes and objective task difficulty on effort mobilization.

In the fourth study, we focused on the joint impact of implicit affect primes and monetary incentive. As observed in the Study 3, in a difficult task context, sadness primes lead to disengagement and masked anger prime to an increase of effort intensity. In this study, we investigated the question if incentive in a difficult task context can eliminate the effort deficit of people primed with sadness, leading to higher effort than in the implicit anger condition.

45 II.2. Studies 1 and 2

: The Facilitating Effect of Implicit Anger: More Evidence in Terms of Effort-Related Cardiovascular Response

Freydefont, L., Gendolla, G. H. E., & Silvestrini, N. (2012). The facilitating effect of implicit anger: more evidence in terms of effort-related cardiovascular response.

Manuscript submitted for publication.

II.2.1.Abstract

Previous studies have revealed that implicit anger leads, under “do-your-best”

instructions, to weaker effort-related cardiac response than implicit sadness (Gendolla &

Silvestrini, 2011). The present two experiments further tested whether implicit anger has a facilitating effect during task performance. Both studies assessed cardiovascular activity during a habituation period and a cognitive task during which participants were exposed to suboptimally presented facial anger vs. neutral vs. sadness expressions. In Experiment 1, cardiac pre-ejection period (PEP) reactivity was weaker in the anger-prime condition than in the neutral-prime condition, but only during the first minute of task performance.

In Experiment 2, PEP reactivity was weaker with anger primes than with both neutral and sadness primes. The findings further support the implicit-affect-primes-effort model (IAPE; Gendolla, 2012) and suggest a facilitating effect of implicit anger during task performance.

Key words: Anger, Implicit affect, priming, effort-related cardiac response.

47 II.2.2. Introduction

Recent studies from our laboratory have revealed that implicit affect priming systematically influences effort-related cardiovascular response (e.g., Freydefont &

Gendolla, 2012; Freydefont et al., 2012; Gendolla & Silvestrini, 2011). In these studies, implicit anger primes had a different impact on effort mobilization than sadness primes:

When participants performed under “do-your-best” instructions, implicit anger led to weaker cardiovascular response than implicit sadness. However, our previous studies did not involve neutral prime control conditions. Thus, it is still questionable if implicit anger really has a facilitating effect during task performance, as suggested by the implicit-affect-primes-effort model (IAPE; Gendolla, 2012)—the theoretical framework that guided this research. To investigate this issue, the present studies compared implicit anger primes’ effects on effort-related cardiovascular response with those of a neutral-prime control condition and a sadness-prime condition.

II.2.2.a. Implicit Affect and Effort Mobilization

Numerous studies have demonstrated that masked affective stimuli systematically influence evaluative judgments and human behavior (e.g., Murphy & Zajonc, 1993;

Öhman, Flykt, & Lundquist, 2000; Winkielman, Berridge, & Wilbarger, 2005). Implicit affect priming has these effects through the activation of mental representations of emotions (Zemack-Rugar, Bettman, & Fitzsimons, 2007). As masked words or objects can activate semantic knowledge in long-term memory (see Förster & Liberman, 2007 for a review), affect primes can influence evaluative judgments and behavior by activating emotion concepts in memory (see Niedenthal, 2008).

Recent studies from our laboratory tested the idea that affect primes that are processed during task performance systematically influence the level of experienced task demand and effort (Freydefont & Gendolla, 2012; Freydefont et al., 2012; Gendolla &

Silvestrini, 2011; Lasauskaite, Gendolla, & Silvestrini, in press; Silvestrini & Gendolla, 2011b, 2011c). According to the IAPE model (Gendolla, 2012), affect primes implicitly activate mental representations of the respective affective states that contain acquired information about performance ease and difficulty that is typical for the respective emotions, leading to experiences of lower or higher task demand during performance.

Task demand, in turn, determines effort intensity as long as success is possible and

48 justified, as outlined in motivational intensity theory (Brehm & Self, 1989; see Gendolla, Wright, & Richter, 2012 for a recent review). Supporting these ideas, studies based on the IAPE model have found that sadness primes indeed lead to stronger effort-related cardiac response than both happiness and anger primes, when people perform under “do-your-best” instructions (Gendolla & Silvestrini, 2011). These effects occurred because sadness primes led to higher subjective task demand and in turn to stronger effort-related cardiac response. Follow-up studies further confirmed the differential effect of implicit anger vs.

sadness on effort-related cardiac response (Freydefont & Gendolla, 2012; Freydefont et al., 2012).

II.2.2.b. Anger Effects

Additionally to our research on the systematic impact of implicit anger on effort-related cardiac response discussed above, there is more evidence that anger stimuli influence evaluative judgments (Smits & Kuppens, 2005), behavior (Wacker, Hedmann,

& Stemmler, 2003), and attention (van Honk, Tuiten, de Haan, van den Hout, & Stam, 2001). Although anger has negative valence, numerous studies have shown that it shares motivational properties with positive affect (Carver & Jones, 2009; Jones, 2003a). Anger is associated with an approach orientation (Carver & Harmon-Jones, 2009; Harmon-Harmon-Jones, 2003b) and, most relevant, anger is linked to high optimism and experiences of high control (Lerner & Keltner, 2001). Moreover, Putman, Hermans, and van Honk, (2004) found a facilitating effect of angry faces on selective attention. In this study, participants with low trait anger faster identified colors in a Stroop task when they were exposed to angry faces than when neutral faces were presented. Altogether, this suggests that anger should have a facilitating effect on behavior: Anger should be associated with ease.

II.2.2.c. Effort-Related Cardiovascular Response

According to Wright’s (1996) integration of motivational intensity theory (Brehm

& Self, 1989) with Obrist’s (1981) active coping approach, beta-adrenergic sympathetic impact on the heart responds proportionally to the level of experienced task demand as long as success is possible and justified. Noninvasively, beta-adrenergic impact is best assessed as increased cardiac contractility and thus shortened cardiac pre-ejection-period

49 (PEP)—the time interval between the beginning of left ventricular excitation and the opening of the aortic valve (Berntson, Lozano, Chen, & Cacioppo, 2004). In support of Wright’s integrative model, PEP sensitively responds to variations in experienced task demand (Richter, Friedrich, & Gendolla, 2008), incentive value (Richter & Gendolla, 2009), and combinations of both (Richter, 2010b; Silvestrini & Gendolla, 2011a).

Numerous studies have also quantified effort as reactivity of systolic blood pressure (SBP), which is systematically influenced by cardiac contractility through its impact on cardiac output (see Gendolla & Richter, 2010; Wright & Kirby, 2001).

However, both systolic and diastolic blood pressure (DBP) are also influenced by peripheral vascular resistance, which is not systematically influenced by ß-adrenergic impact (Levick, 2003) and can mask contractility effects on SBP and DBP. Still other studies (e.g., Eubanks & Wright, 2002) have quantified effort as responses in heart rate (HR). However, HR is influenced by both sympathetic and parasympathetic impact and should only reflect effort mobilization if the sympathetic impact is stronger (Berntson, Lozano, Chen, & Cacioppo, 2004). Consequently, PEP is the most reliable and valid indicator of effort intensity among these parameters (Kelsey, 2012). Nevertheless, PEP should always be assessed together with blood pressure and HR to control for possible pre-load (ventricular filling) or after-load (arterial pressure) effects (Sherwood et al., 1990).

II.2.2.d. Overview Over the Present Studies

Our primary goal was to test the facilitating effect of implicit anger during task performance using cardiovascular measures. Moreover, we aimed to provide additional evidence for the IAPE model (Gendolla, 2012) idea that the effects of affect primes on effort-related cardiovascular response are emotion category-specific rather than valence-specific. If the effect is emotion category-specific, anger primes should have different effects than primes of other negative emotions that are associated with difficulty.

Therefore, we contrasted the effects of anger primes not only against a neutral prime

Therefore, we contrasted the effects of anger primes not only against a neutral prime