Primary Biological Motivators in Food Advertisements: Energy Density and Sexual Appeals Compete for Appetitive Motivational Activation

Abstract

Energy density of food potentiates appetitive responses due to biologically driven behaviors that encourage energy conservation. Sexual stimuli potentiate appetitive responses due to biologically imperative needs to pass on genetic information. This article examined how these primary biological motivators, when presented together, influenced individuals’ responses to food advertisements. Competing hypotheses were developed using communication and behavioral ecology theory and tested in two studies. Young adults viewed food advertisements that varied in presence of sex appeal and the energy density level of the food advertised. Psychophysiological responses, recognition memory, and self-reported emotional experience data were obtained. In general, results support an ecological interpretation in which these motivators can be viewed as competing rather than additive. Furthermore, sex of the viewer plays a role in response to these motivators that may be attributable to differences in the costs of procreative activities for males and females.

Keywords

biological communication food advertising sex appeal motivation optimal foraging

Using highly sexualized appeals in food advertisements is a growing trend, especially in the fast food industry (e.g., Carl’s Jr., Burger King). These ads have been described as, “a pornographic convergence of hot-off-the-grill hamburgers with hot-and-bothered writhing” with the acknowledgment that these advertisers are exploiting our “dual appetites” for both food and sex (Beckerman, 2010, para. 7). However, little is known regarding how the dual presentation of these appetitive stimuli affects the cognitive and emotional processing of information. Both food-related and sex-related information are part of a set of stimuli known as primary biological motivators or “reinforcers” that automatically evoke behaviors to further biological imperatives (Bradley, Codispoti, Cuthbert, & Lang, 2001). Research using the Limited Capacity Model of Motivated Mediated Message Processing (LC4MP; A. Lang, 2006) as a framework has examined how primary biological motivators in mediated contexts guide information processing, emotional reactions, and behaviors. A decade of this work has found that appetitive primary biological motivators elicit increases in positive emotional experience, encoding, and storage (see Sparks & Lang, 2015). However, relatively little research has examined processing of concurrently presented primary motivators.

To fill this gap, this article presents two studies that investigated whether the presence of sexual stimuli and foods of different biological value (i.e., energy value) may provide either additive appetitive influences on cognitive and emotional processing or actually inhibit one another. Competing hypotheses derived from the LC4MP and relevant theory from behavioral ecology, optimal foraging theory (Pyke, Pullium, & Charnov, 1977; Schoener, 1971), were developed to understand how these biologically motivating elements play a role in states of motivation, emotion, information processing, and behavior. It is proposed that qualitatively different processing states can be achieved via these contents that are, under the LC4MP, thought to be of similar motivational value in terms of experience created and cognitive processing patterns elicited. Understanding more about this message content combination will add nuance to motivated cognition theory (Bradley et al., 2001; A. Lang, 2006), especially as it concerns media processes and effects.

Motivated Cognition: The Role of Primary Biological Motivators

Motivation is considered here to be activation in either or both of two motivational systems, the appetitive and the aversive, that evolved to help organisms respond to stimuli appropriately (see Bradley et al., 2001; Cacioppo, Berntson, Norris, & Gollan, 2012; P. J. Lang, Bradley, & Cuthbert, 1997). In general, activation of these motivational systems guides attention, information processing, and affect (Bradley et al., 2001; Cacioppo & Gardner, 1999; P. J. Lang et al., 1997). The appetitive system is activated in contexts relating to food imagery, sexual imagery, and other elements that provide biological opportunities; the aversive system is activated in contexts relating to threat (Bradley et al., 2001; P. J. Lang et al., 1997). The main goal of appetitive activation is information intake in the pursuit of biological opportunities at the expense of processing other, potentially more extraneous, details (A. Lang, 2006; P. J. Lang et al., 1997). For example, the appetitive system prioritizes processing of food stimuli due to its survival relevance. The main goal of aversive motivational activation is initial identification of danger followed by avoidance (Bradley et al., 2001). Thus, threats automatically elicit aversive activation. Affect is considered an indication of activation in these motivational systems. Dimensional emotion theory (Bradley et al., 2001) posits that the activation in one or both motivational systems contributes to emotional valence (pleasant, unpleasant, ambivalent, neutral) while the intensity of the activation contributes to emotional arousal.

Over a decade of research using the LC4MP has tested these propositions and found that cognitive resource allocation, emotional response, and encoding and storage of information follow predicted patterns based on the activation functions of these evolved motivational systems (e.g., A. Lang, Potter, & Bolls, 2009; A. Lang, Park, Sanders-Jackson, Wilson, & Wang, 2007). In general, the LC4MP posits that motivationally relevant content in media—content relevant to an individuals’ biological success—automatically activates the appetitive and/or aversive systems, which then predispose attention, experiences, and behaviors in ways that would be most beneficial to survival and reproduction (A. Lang, 2006). Among this class of motivationally relevant content is a limited category of items called primary biological motivators, which deal directly with survival (i.e., threat, wounds, illness), energy conservation (i.e., food, shelter), and procreation (i.e., sexual stimuli; Bradley et al., 2001). Motivationally relevant content also includes emotional contexts (e.g., light vs. dark), social cues (e.g., happy vs. angry facial expressions), and objects that present opportunities or threats based on current needs of the viewer (e.g., fire, weapons, animals; A. Lang & Bailey, 2015).

Food as a Primary Biological Motivator

Food-related stimuli are part of the set of motivationally relevant stimuli that are considered primary motivators (Bailey, 2015, 2016; Bradley et al., 2001) because organisms need food to survive. Research has shown that both real and mediated food cues automatically activate reward regions in the brain as well as increase later food consumption independently of ratings of subjective hunger/food craving (Lawrence, Hinton, Parkinson, & Lawrence, 2012). However, food stimuli are not created equally with regard to the appetitive responses they elicit. Previous research has shown that mediated food cues that share some perceptual characteristics of actual food (i.e., color, texture, temperature of food) create automatic approach responses, more positive attitudes toward the ad and brand, more purchase intention, faster and stronger intentions to eat the food, and greater choice of foods for actual consumption (Bailey, 2015, 2017). Furthermore, the energy content of foods is highly influential. When highly energy dense (i.e., greater energy content per gram) food cues shared some perceptual characteristics of the food, food items were selected for eating faster than less energy dense foods and more energy dense foods without available cues (Bailey, Wang, & Liu, 2018).

The finding that energy density of foods alters preference is far from new. For example, rats fail to adjust food intake based on homeostatic need and consume their regular food but also eat previously cued foods as well when they are available (Reppucci & Petrovich, 2012). This indicates something quite important about eating behavior—it is driven by environmental opportunities and constraints with safeguards constantly in place for lean times. For this reason, organisms tend to show a preference for more energy dense high fat, high sugar foods (Drewnowski, 1997; Toepel, Knebel, Hudry, le Coutre, & Murray, 2009), especially when they are easily obtained. Energy dense foods speed human information processing (Harrar, Toepel, Murray, & Spence, 2011) and motivated decision making (Bailey, Wang, & Liu, 2018) and activate brain areas important for identifying motivational relevance (Killgore et al., 2003; Toepel et al., 2009). When individuals need to replenish their energy stores, energy dense foods are even more preferred (Stoeckel, Cox, Cook, & Weller, 2007). Thus, not only is food a primary motivator, energy dense food is even more motivating, all else being equal.

Sex-Related Stimuli as Primary Biological Motivators

Sex-related stimuli are also primary motivators (Bradley et al., 2001; P. J. Lang, Greenwald, Bradley, & Hamm, 1993; Sparks & Lang, 2015). The passage of genetic information on to offspring, which is a biological imperative, relies on sexual behavior. For this reason, sexual stimuli, in real or mediated contexts, elicit automatic motivational responses that yield greater arousal (P. J. Lang et al., 1993), attention (A. Lang, Wise, Lee, & Cai, 2003; Sparks & Lang, 2015), and memory than nonsexual content (King, McClelland, & Furnham, 2015; Leka, McClelland, & Furnham, 2013). Furthermore, sex-related stimuli create more positive emotional responses (Geuens & De Pelsmacker, 1998; Sparks & Lang, 2015) and greater intentions to purchase products (Reichert, Heckler, & Jackson, 2001) due to their appetitive influences. Thus, both sex-related stimuli and food-related stimuli, especially of the most energy dense varieties, are considered primary appetitive motivators that elicit more, and in some cases faster, information processing as well as more appetitive and positive emotional responses. This article, however, seeks to understand what happens when they are presented concurrently.

Dual Motivational Activation: What Do We Know?

While the LC4MP has been successful in predicting how motivational activation in single systems influences information processing, emotion, and memory, less is understood regarding how combinations of appetitive and aversive motivationally relevant content come together to influence these outcomes. A few studies have begun to investigate one class of such content, coactive or ambivalent messages, which contain both appetitive and aversive content in varying amounts (Keene & Lang, 2016; Wang, Solloway, Tchernev, & Barker, 2012). Even fewer studies have examined how multiply-appetitive or multiply-aversive content have functioned (e.g., Leshner, Bolls, & Thomas, 2009; Sparks & Lang, 2015). In a multiply-aversive context, the LC4MP has been used to predict a somewhat additive response. For example, in anti-tobacco advertisements, the presence of fear- and disgust-inducing content were examined by themselves and together with the prediction that both together would be more likely to elicit defensive processing (Leshner et al., 2009), which was generally supported. In a multiply-appetitive context, Sparks and Lang (2015) also predicted an additive response. Sex and humor content were presented together and separately, and cognitive resource allocation, recognition, and motivational and emotional responses were examined. Results indicated that the addition of humor to sex produced less appetitive motivation than humor- or sex-only messages in appetitive foreground messages. To explain this, the authors argued that the messages that introduced appetitive stimuli—sex, humor, sex and humor—into already positive contexts created a ceiling effect in appetitive activation, yielding no change. This is one potential explanation that still views appetitive activation in a multiply-appetitive context to be additive.

An alternative explanation may be that the addition of humor to sex produces a qualitatively different appetitive state than sex or humor alone. From a neuroscientific perspective, it has been argued that the functional and structural networks supporting an organism’s attentional and affective systems are dynamical and, as such, rely on complex feedback and feedforward mechanisms that function at different time courses to help organisms behave in the most adaptive ways possible in different circumstances (Thayer & Friedman, 1997; Thayer & Lane, 2000). Therefore, when humor is introduced into a sexual context, this may inhibit appetitive activation driving sexual behaviors and result in a different affective, behavioral, and attentional state than the sexual stimuli alone.

The same is likely true when food-related stimuli are introduced into a sexual context. From a behavioral point of view, eating and having sex are at odds with one another and rarely occur together. Because the appetitive activation that is automatically occurring in response to these cues is occurring to gear the body up for adaptive action to actually approach opportunities (Bradley & Lang, 2000; Thayer & Lane, 2000), it may be best to consider how this appetitive activation will be used in service of behavior. Thus, it may make the most sense to consider which opportunity would be more biologically important to approach—food or sex? In this regard, LC4MP does not provide a prediction. Instead, we turn to theory from behavioral ecology.

Optimal foraging theory (Pyke et al., 1977; Schoener, 1971) posits that animals must search and acquire food in ways that maximize their potential to pass on genetic information most successfully (i.e., maximize fitness). Schoener’s (1971) original argument was that organisms select a “currency” that provides the most benefit to their ultimately achieving this goal. Energy that keeps bodily systems functioning until gene passage is the commonly assumed currency for animals. Thus, optimal foraging theory suggests that animals, including humans, will optimize their eating to maximize their net energy intake (i.e., energy gained by eating food minus the energy used to obtain it). This optimization ensures that energy needs are more likely to be met at all times via energy stores (i.e., body fat) if foraging turns up nothing. What this means behaviorally is that individuals will prefer the most energy dense foods they can find, but if they encounter other food along the way that is low cost to obtain, they will consume this in the interim, especially if they are in need of energy.

Because the assumed ultimate goal, biologically, is passage of genetic material, sexual stimuli that are likely to result in gene passage should be more motivating than food. However, if both options are concurrently available, the seeking of one of these biological opportunities generally means forgoing the other. Which is selected for approach may depend on the level of satiation in the organism as well as the opportunity cost of forgoing one or the other. Stimuli that signal sexual opportunities are not guarantees of sexual activity or procreation; food may be more motivating when sexual stimuli are present but indicate less opportunity. If sexual stimuli are present, approaching them when losing out on less energy dense foods would be more beneficial than approaching them when losing out on more energy dense foods. If sexual stimuli are not present, approaching more energy dense foods would be more beneficial than approaching less energy dense foods, all else being equal. This reasoning would support the prediction that if sexual stimuli and highly energy dense foods are concurrently present, approach of one may inhibit approach of the other. Therefore, this article tests two competing hypotheses derived from these different theoretical perspectives. The first, derived from the LC4MP and empirical work conducted using its framework, predicts additive appetitive activation when two highly motivating stimuli are present:

Competing Hypothesis 1 (CH1): The combination of more energy dense foods with sexual stimuli will elicit greater appetitive motivational activation and better encoding than less energy dense foods with sexual stimuli, more energy dense foods without sexual stimuli, or less energy dense foods without sexual stimuli.

The second was derived from neurovisceral dynamic models and optimal foraging theory, which would predict inhibited appetitive activation:

Competing Hypothesis 2 (CH2): The combination of sexual stimuli and more energy dense foods will elicit less appetitive motivational activation and poorer encoding than less energy dense foods with sexual stimuli and more energy dense foods without sexual stimuli.

These hypotheses were tested in experiments using a food advertising context. Individuals viewed ads for more and less energy dense foods that contained a sexual appeal or did not. During exposure, individuals’ psychophysiological responses were obtained to index dynamic motivational activation and attention. Postexposure self-reported emotion and visual recognition were obtained to examine emotional and cognitive processing resulting from this motivational activation.

Study 1

Method

Design

A 2 (food energy density: more, less) × 2 (sexual appeal: present, absent) × 2 (repetition) × 2 (order of presentation) mixed factorial design was used. Order was the only between-subjects factor. This design limited the influence of individual differences on the dependent variables, especially the psychophysiological metrics, which tend to have high intersubject variability. Order was used to control for carryover effects. The repetition factor here means that advertisements for two different food product/brands were used in each combination of manipulations. This allowed for better generalization of results to ad stimulus types rather than individual ads/brands/products. Therefore, a total of eight recent 17 to 20 second English-language advertisements were selected that varied in food energy density and sexual appeal.¹ Food energy density was manipulated based on the amount of kcal per gram of food advertised (e.g., Little Debbie snack cakes 5.43 kcal/g were more energy dense than Baby Carrots snack packs 0.44 kcal/g). Sexual appeal was manipulated based on the way food was consumed in the ads. In half the ads, food was eaten in a sexually provocative manner. In the other half, the food was eaten in a nonsexually provocative manner. A separate pretest ensured that the sexual appeals were perceived as more sexually oriented. Participants (N = 83) watched each ad and rated, on 7-point scales from 1 (not at all) to 7 (very), how much the ad attempted to use sexual imagery and how sexy the ad was to the participant. These items were correlated, r = .80. Analysis of the index of these items confirmed sexual ads (M = 5.19, SE = .11) were rated sexier than nonsexual ads (M = 1.79, SE = .09), F(1, 82) = 620.35, p < .001, η² = .88.

Participants

Participants (N = 42) were undergraduates at a Northwestern university who received extra credit for participating. These participants were young (M = 21.76 years, SD = 5.82), primarily female (59.5%), and predominantly Caucasian (86%). One participant elected not to participate in psychophysiological data collection. One recognition file was lost due to corruption. Specifying a small effect size (.20) and an α of .05 in the G*Power program (Faul, Erdfelder, Lang, & Buchner, 2007), the proposed design requires at least 36 participants to have a .95 power estimate.

Dependent variables

Psychophysiological metrics

Heart rate (HR), skin conductivity level (SCL), and two channels of facial electromyography were collected to index attentional resource allocation, emotional arousal, and emotional valence, respectively (see Fridlund & Cacioppo, 1986; P. J. Lang et al., 1993; A. Lang et al., 2009; Potter & Bolls, 2012). Appropriately sized floating Ag-AgCL surface electrodes were affixed to the participants’ forearms (HR), palms (SCL), and over the left orbicularis oculi (OO; smiling) and corrugator supercilii (CS; frowning) facial muscle groups. These data were collected using a Biopac MP150 unit with wireless bioamplifier modules. Greater detail regarding collection procedures, sampling, filtering, and quantification can be found in Online Appendix B.

Recognition

A forced-choice speeded visual recognition task was developed to examine visual encoding of information. Two targets were obtained by taking screenshots from each ad. Two visually matched foils were obtained by taking screenshots from similar ads that the participants did not view. These screenshots were presented one at a time in a random order. Participants were instructed to press one of two response keys that indicated “Yes” if they had viewed the image or “No” if they had not as quickly as they could without sacrificing accuracy. DirectRT software (Jarvis, 2014) was used to deliver the stimuli and collect the responses.

Self-reported emotional experience

Following Lee and Lang (2015), and Wang, Morey, and Srivastava (2014), we measured self-reported arousal, positivity, and negativity using 7-point semantic differential questions (anchored by 1 = not at all and 7 = very) after each ad. The questions were structured in the following way: How aroused/positive/negative did you feel while viewing this ad? Arousal was always asked first. Positivity and negativity were asked next in a randomly assigned order.

Procedure

Upon arrival to the lab, participants’ informed consents were obtained. Participants completed the protocol individually. First, they were seated with access to a computer keyboard and prepped with physiological data collection sensors. Then, the participants viewed each ad presented in one of two counterbalanced orders while their physiological measures were obtained. After each, they rated the ad on the specified emotional experience scales. MediaLab software (Jarvis, 2014) was used to deliver the experimental stimuli and questionnaires. After participants completed viewing and rating each ad, the participants were asked to complete some food knowledge and behavior questionnaires as well as demographics. Then, participants were debriefed, thanked, and dismissed. The entire procedure lasted between 45 and 60 minutes.

Data reduction and analysis

HR, SCL, OO, and CS data were sampled at 1,000 Hz and averaged into half-second intervals. Change data were computed using the half-second of ad onset as the reference point. Proportion correct recognition data were computed. These data and the self-reported emotion data were submitted to a 2 (food energy density) × 2 (sexual appeal) × 2 (repetition) repeated-measures analysis of variance (ANOVA). The psychophysiological data were submitted to the same model with the addition of a time factor that included 34 half seconds of measurement across ad exposure. The p values and degrees of freedom corrected for sphericity assumption violation using the Greenhouse-Geisser method are reported where appropriate. HR data were not significant at any level and will not be discussed further.

Results

Appetitive motivational activation and emotional experience

CH1 predicted that the combination of sexual stimuli and greater energy density would create greater appetitive motivational activation (indicated by greater SCL, more OO activation/less CS activation, greater self-reported arousal and positivity, and less self-reported negativity) than sexual stimuli paired with less energy dense foods, and more and less energy dense foods without sexual stimuli. CH2 predicted that the combination of sexual stimuli and greater energy density would elicit less appetitive motivational activation (indicated by lower SCL, less OO activation/more CS activation, and lower self-reported arousal and positivity) than sexual appeals for less energy dense foods or more energy dense foods not using sex appeals. For either of these competing hypotheses, the prediction was an interaction of sexual stimuli and energy density. This was found on SCL, F(1, 39) = 5.02, p = .031, η² = .11, but not OO and CS (Fs < 1). Sexual stimuli and energy density also interacted with time on SCL, F(33, 1287) = 1.74, p = .01, η² = .04, but not on OO or CS (Fs < 1). Figure 1 illustrates this SCL pattern across exposure to the ads. All ads elicited increases in skin conductivity, but the increase was greatest in response to the ads for more energy dense foods not using sexual appeals, followed by ads for less energy dense foods using sexual appeals and ads for more energy dense foods using sexual appeals. SCL data suggest that the combination of sexual stimuli and more energy dense foods created less intense motivational activation, a result in support of CH2.

Figure 1.

SCL change over times as a function of sexual appeal and ED.

The self-reported emotional experience variables do not map onto these psychophysiological responses. The predicted interaction of energy density and sexual stimuli did not achieve significance in self-reported negativity, positivity, or arousal. Thus, results failed to support either hypothesis. Main effects of sexual stimuli were present across the board, self-reported arousal, F(1, 41) = 4.77, p = .040, η² = .10; positivity, F(1, 41) = 7.08, p = .011, η² = .15; and negativity, F(1, 41) = 15.73, p < .001, η² = .28, such that ads that contained sex appeal were more arousing, less positive (though still above the midpoint), and more negative than those that did not (see Table 1 for means).

Table 1.

Means (Standard Deviations) for Self-Reported Emotional Experience Variables.

Ad type	Self-reported arousal	Self-reported positivity	Self-reported negativity
Study 1
Sexy	4.48 (1.10)	4.01 (1.29)	3.17 (1.27)
Nonsexy	4.02 (0.98)	4.64 (0.96)	2.30 (0.91)
Less ED	4.01 (0.99)	4.19 (1.01)	2.88 (1.02)
More ED	4.48 (0.98)	4.45 (1.01)	2.59 (0.97)
Study 2
Sexy	4.11 (1.27)	3.99 (1.20)	2.49 (1.18)
Nonsexy	3.27 (1.12)	4.57 (1.15)	1.83 (0.84)
Less ED	3.71 (1.02)	4.23(1.04)	2.20 (0.89)
More ED	3.68 (1.17)	4.35 (1.08)	2.12 (0.86)

Note. ED = energy density.

Encoding

CH1 predicted that the combination of sexual stimuli and greater energy density would result in better encoding than sexual stimuli paired with less energy dense foods, and more and less energy dense foods without sexual stimuli. CH2 predicted that the combination of sexual stimuli and greater energy density would elicit less appetitive motivational activation than sexual stimuli paired with less energy dense foods, and more energy dense foods without sexual stimuli, resulting in less well encoded information. Again, the prediction was an interaction of sexual stimuli and energy density. This was found on recognition proportion correct, F(1, 41) = 6.70, p = .013, η² = .14. Recognition for all ads was better than chance, but the proportion correct for less energy dense food ads without sexual appeals was least well recognized (M = .67, SE = .04). All other types did not differ significantly (sexual appeal more energy dense [M = .83, SE = .04], no sexual appeal more energy dense [M = .82, SE = .04], sexual appeal less energy dense [M = .89, SE = .03]). Table 2 contains paired comparisons. Results failed to support either hypothesis.

Table 2.

Paired Comparisons for ED and Sex Appeal Interactions.

Recognition Comparisons	t	df	p (2-tailed)
Study 1
Sexy less ED vs. sexy more ED	1.220	41	.23
Sexy less ED vs. nonsexy less ED	3.609	41	.001*
Sexy less ED vs. nonsexy more ED	1.232	41	.23
Sexy more ED vs. nonsexy less ED	2.804	41	.008*
Sexy more ED vs. nonsexy more ED	0.1980	41	.844
Nonsexy less ED vs. nonsexy more ED	0.2.614	41	.012
Study 2, females only
Sexy less ED vs. sexy more ED	2.227	34	.04
Sexy less ED vs. nonsexy less ED	2.953	34	.006*
Sexy less ED vs. nonsexy more ED	0.3290	34	.744
Sexy more ED vs. Nonsexy less ED	0.8280	34	.413
Sexy more ED vs. Nonsexy more ED	1.642	34	.110
Nonsexy less ED vs. nonsexy more ED	2.315	34	.027
Study 2, males only
Sexy less ED vs. sexy more ED	0.4660	36	.64
Sexy less ED vs. nonsexy less ED	0.0000	36	1.0
Sexy less ED vs. nonsexy more ED	0.7700	36	.50
Sexy more ED vs. nonsexy less ED	0.5290	36	.60
Sexy more ED vs. nonsexy more ED	0.2260	36	.82
Nonsexy less ED vs. nonsexy more ED	0.7700	36	.50

Note. ED = energy density.

Significant after Bonferroni correction for multiple comparisons (adjusted alpha = .008).

Discussion

This study examined how the co-presentation of food and sexual stimuli affected the motivational response and information processing of mediated messages. Two competing hypotheses were developed from extant theory in communication, neuroscience, and behavioral ecology. The LC4MP-derived hypothesis predicted additive appetitive activation, while the optimal foraging-derived hypothesis predicted inhibitive appetitive activation. In general, these data offer greater support to the inhibitive hypothesis than the additive hypothesis. SCL data indicated that more energy dense foods that did not use sexual appeals elicited the most sympathetic arousal. These data also indicated that more energy dense foods using sexual appeals elicited less sympathetic arousal than sexual appeals for less energy dense foods. This supports that these two primary biological motivators are competing, or inhibiting each other. When rewarding food and sexual opportunities are cued together, there seems to be underlying automatic inhibition that precludes approach toward one or the other type of stimuli. In this food advertising context where food is persistently present, albeit more and less energetically valuable, this automatic inhibition affects self-reported emotional experiences as well. No differences for energy density were found, but sexual appeal did create differences.

However, this inhibition does not seem to affect the automatic allocation of resources to processing. Encoding of information was high overall and the only ad type that showed lesser encoding was less energy dense foods without sex appeal. Though the additive hypothesis was not necessarily supported here—the more energy density sexual appeal ads were not best encoded—the inhibition hypothesis was not either. From both perspectives—because both share biological imperative assumptions—it makes sense that biological motivators would draw encoding resources. Though organisms need to prioritize energy expenditures to create the greatest net energy, remembering where opportunities may be in the future may save resources that would otherwise be used searching would be adaptive. Thus, the dual presentation of appetitive motivators elicits disparate emotional responses but potentially better memory. From a practical point of view, this means individuals may remember the ad but not like it as much.

Though these data are interesting, certain limitations need to be addressed. First, it may be that sex of the viewer plays an important role that is missed here. The ads include sexual appeals that may appeal more to males: mainly women eating foods in sexually provocative ways. Though females have been shown to be more generalized in their sexual arousal responses (Baumeister, 2000; Chivers, Rieger, Latty, & Bailey, 2004), it may be that the sexes have different responses to these appeals for various reasons. From a socialization perspective, the perceived sexiness of these appeals as well as their appropriateness may differ, which would influence both cognitive and emotional reactions. From a parental investment perspective (Trivers, 1972), the immediate costs of procreative activities are similar between males and females, but the long-term costs are potentially far higher for females in terms of child rearing. In either case, sex of the viewer may influence motivational responses.

Furthermore, current appetitive states of need for energy and/or desire for sexual interaction may be even more important drivers of motivational responses than sex of the viewer. Though individuals automatically respond to stimuli they encounter in their environments, they also tend to focus on what they need or want. Ecological perception theory (Gibson, 1977) argues that humans automatically perceive what behaviors are afforded by different environmental stimuli (i.e., objects, substances, other animals, and humans). In other words, humans automatically detect what can be done with stimuli they encounter and much of this is predicated on what they need. Therefore, if one needs energy, or in search of potential mates, this potentiates contextually appropriate behaviors more readily when stimuli that might meet these needs. Thus, understanding how sex of the viewer and individual differences in food and mate seeking tendencies interact with sexual appeal and energy density to influence motivational, emotional, and cognitive processing of ads may shed light on which of the competing hypotheses—additive appetitive activation (LC4MP) or inhibitive appetitive activation (optimal foraging)—is more supported. Therefore, a second study was performed with minor changes in the protocol: A new set of participants was asked to indicate their sex and partner preferences as well as their current food and mate seeking interests before completing the study.

Study 2

Method

Design

The study design is replicated from Study 1 with two changes: the inclusion of sex of the viewer as a 2 factor (male, female) between-subjects variable, and the inclusion of two covariates: food and mate seeking interest. Food seeking interest was assessed using the index of two items. Participants used a 7-point scale (1 = not at all, 7 = very) to indicate their interest in finding and eating food currently and how hungry they were currently. These items were correlated, r = .77. Participants were, on average, moderately interested in eating food (M = 4.27, SD = 1.33). There was no significant difference between males and females in food-seeking interest, F(1, 72) = 1.07, p = .305. Mate seeking interest was assessed using the index of two items. Participants used a 7-point scale (1 = not at all, 7 = very) to indicate their interest in finding sexual partners currently and their interest in having sex currently. These items were correlated, r = .81. Participants were, on average, less interested in sexual behaviors (M = 3.18, SD = 1.62). Males (M = 3.74, SD = 1.66) reported greater mate-seeking interest than females (M = 2.59, SD = 1.36), F(1, 72) = 10.38, p = .002.

Participants

Participants (N = 73) were undergraduate students at a Northwestern university. These participants were young (M = 20.03, SD = 2.27), predominantly Caucasian (80.8%) and heterosexual (90%). The sample was almost evenly split between males (n = 38) and females (n = 35). Sexual partner preference did not directly or in coalition with the manipulated independent variables influence the dependent variables and will not be discussed further. Due to equipment error or excessive artifact, 10 participants were excluded from psychophysiological data analysis. Specifying an effect size similar to that found in Study 1 and other psychophysiological studies (.15), and an α of .05 in the G*Power program (Faul et al., 2007), the proposed within-between interaction repeated-measures design requires at least 62 participants to have a .95 power estimate. A smaller effect size was used to estimate power here to ensure that the psychophysiological metrics, which generally have small effects, were adequately powered.

Manipulation check

Participants used a 7-point scale (1 = not at all, 7 = very) to indicate how much the ad used a sexual appeal and how sexy the appeal in the ad was to the participant. These items were correlated, r = .81. Analysis of the index of these items indicates that sexual appeal ads (M = 5.19, SD = 0.12) were rated sexier than the nonsexual appeal ads (M = 1.64, SD = 0.08), F(1, 71) = 989.97, p < .001, η² = .93. No significant differences in this index were due to sex of the viewer, F < 1.

Procedure

Minimal changes to the procedure reported in Study 1 were made in Study 2. Participants were asked to report individual differences in mate and food seeking interests and sexual partner preference directly after being prepped with psychophysiological sensors (before seeing any experimental stimuli). After each ad, they were asked to rate the ad on the specified emotional experience scales but also were asked manipulation check questions.

Data analysis

The self-reported emotion and encoding data were submitted to a 2 (food energy density) × 2 (sexual appeal) × 2 (repetition) × 2 (sex of the viewer) repeated-measures analysis of covariance (ANCOVA). The psychophysiological data were submitted to the same model with the addition of the time factor. Food and mate seeking interest indices were entered as covariates. The p values and degrees of freedom corrected for sphericity violation using the Greenhouse-Geisser method are reported.

Results

Appetitive motivational activation and emotional experience

The two competing hypotheses—additive and inhibitive—were tested again. For either hypothesis, the prediction is an interaction of sexual stimuli and energy density. The question here is whether this interaction is moderated by sex of the viewer after controlling for food and mate seeking interest individual differences. After these controls, no differences based on sexual appeal, energy density of food, or sex of the viewer or their interaction were found on CS or OO data. However, a significant interaction of sexual appeal, energy density of food, sex of the viewer, and time was found on SCL, F(2.97, 175.04) = 2.85, p = .040, η² = .05. As shown in Figure 2, sexual appeals for less energy dense foods elicited the most skin conductivity in male viewers. Sexual appeals for more energy dense foods elicited initial increases in arousal, though this tapered off steeply. Female viewers exhibited the greatest skin conductivity during ads for more energy dense foods that did not use sexual appeals.

Figure 2.

SCL as a function of sex of the viewer, sexual appeal, and ED.

Sex of the viewer also moderated self-reported emotional responses after controlling for the individual differences. The means are displayed in Figure 3. The interaction of sexual appeal and energy density approached significance on positivity ratings, F(1, 69) = 3.10, p = .083, η² = .04, but was moderated by sex of the viewer, F(1, 69) = 5.28, p = .035, η² = .07. Males and females rated ads that did not contain sexual appeals as highly positive. Females rated sexual appeals for more energy dense foods as more positive than sexual appeals for less energy dense foods. Men rated sexual appeal ads for less energy dense foods as more positive than sexual appeal ads for more energy dense foods, though this difference was not significant (t < 1). After controlling for individual differences, the interactions of sexual appeal and energy density with sex of the viewer was not significant on negativity ratings, Fs < 1. However, sex of the viewer was significant as a main effect, F(1, 69) = 5.70, p = .020, η² = .08, such that women rated the food ads overall as more negative than men did though these ratings were below the midpoint of the scale. This was especially the case when women rated food ads that contained sexual appeals, F(1, 69) = 7.85, p = .007, η² = .10. Men and women rated nonsexual appeal ads similarly on negativity. A significant interaction of sexual appeal and energy density was found on arousal ratings, F(1, 69) = 4.56, p = .036, η² = .06, but was not moderated by sex of the viewer, F(1, 69) = 1.59, p = .21. The sexual appeal ads for less energy dense foods were rated as most arousing, though not significantly more than the sexual appeal ads for more energy dense foods, t < 1.

Figure 3.

Self-reported arousal, positivity, and negativity as a function of sex of the viewer, sexual appeal, and energy density.

Encoding

After controlling for individual differences, the interaction of sexual appeal and energy density approached significance, F(1, 68) = 3.04, p = .09, η² = .04, but was not moderated by sex of the viewer, F(1, 68) = 2.58, p = .11, η² = .04. Sexual appeals for less energy dense foods and nonsexual appeals for more energy dense foods yielded best recognition. See Figure 4 and Table 2.

Figure 4.

Recognition proportion correct as a function of sex of the viewer, sexual appeal, and ED.

Discussion

These results indicate that sex of the viewer is important over and above current individual differences in food and mate seeking interest in both sympathetic nervous system activation (i.e., SCL) as well as summative, after-the-fact ratings of positive and negative emotions. Men were more sympathetically aroused when sexual opportunities were presented with less energy dense foods, while women were more sympathetically aroused when more energy dense foods were presented without sexual opportunities. When both sexual opportunity and high energy density foods are present, both men and women are initially sympathetically aroused, potentially gearing up for bodily action, but men show a steeper decline in this activation than women do. This is in line with the idea that men may be more interested in sex when the opportunity cost is low (i.e., less energy dense food) as opposed to when the opportunity cost is high (i.e., more energy dense foods). Women, on the other hand, are less inclined toward sex than men when the opportunity cost is present (i.e., when food is present at all), but because sex is of greater potential long-term energy cost for them (see Trivers, 1972), their preference is for greater energy dense foods. The self-reported emotional responses support this contention. Self-reported arousal differences were not moderated by sex of the viewer, but women rated sexual appeal ads in general as more negative and less positive than men (though, again, their ratings were below the midpoint for negativity) indicating overall positive dispositions toward the ads. However, women rated the sexual appeal ads for less energy dense foods as coactive (about as negative as positive), further indicating a preference to approach foods that would be more likely to meet potential energy expenditures when faced with energy-expending opportunities (i.e., sex).

No differences in OO and CS were found when controlling for food-seeking and mate-seeking interest. However, when these covariates were not included in the model, interactions on both were present: CS, F(33, 1980) = 2.37, p = .035, η² = .04, and OO, F(33, 2013) = 2.53, p = .055, η² = .04, that were not moderated by sex of the viewer. Figures 5 and 6, available in Online Appendix C, illustrate that exposure to ads for less energy dense foods that used sexual appeals elicited the greatest OO activation, and the ads for more energy dense foods that used sexual appeals elicited the least. Furthermore, all ads elicited a decrease in activation in the CS muscle area, which is indicative of greater positive response (Larsen, Norris, & Cacioppo, 2003), except the more energy dense food ads that used sex appeals. These data indicate a less intense and coactive response toward the greater energy dense food ads using sex appeal and a more intense and mostly positive response toward the more energy density foods not using sex appeal. These responses, first and foremost, are indicative of an inhibitive response when both food and sexual stimuli are present, supporting CH2. The fact that these differences are subsumed when controlling for food- and mate-seeking interest further indicates that opportunity costs are influencing how these motivators are approached when presented concurrently.

Overall Discussion

These studies examined how the co-presentation of food and sexual stimuli affected cognitive, motivational, and emotional responses. Two competing hypotheses were developed from theory in communication and behavioral ecology. The LC4MP-derived hypothesis predicted additive appetitive activation, while the optimal foraging-derived hypothesis predicted inhibitive appetitive activation. In general, these data offer greater support to the inhibitive hypothesis. Even after controlling for state-level interest in food and mate seeking, males and females both exhibited less sympathetic arousal when sexual appeals were paired with highly energy dense foods. Females, compared with males, showed greater sensitivity to the opportunity cost of sex as would be expected from a parental investment viewpoint (Trivers, 1972). Males, on the other hand, showed the greatest appetitive activation when food opportunity costs were low and sexual opportunity was apparent.

From an applied perspective, these results indicate using sexual appeals to sell energy dense foods is not necessarily advisable. If a target audience is comprised of males, using a sexual appeal may be more successful for foods that are perceived as lower opportunity cost (i.e., less energy dense). Sexual appeals may be less useful for females in general. However, if the goal is general brand awareness or memory, a sexual appeal may perform well across; all encoding performance was above chance. Future work should examine how specific contents are encoded to better determine whether attentional biases are at work. Future work should also examine how individual differences in cognitive control and executive functioning can influence memory for cues in advertisements as these differences have been found to influence attention and behavior in both sex-seeking (Wasserman, Crockett, & Hoffman, 2017) and food-seeking contexts (Kleiman, Trope, & Amodio, 2016).

These studies are limited in that the participants were young, predominantly Caucasian adults, and the foods were convenience foods. Future research should extend and replicate these findings in other types of individuals with different types of foods that cost more in terms of preparation resources (i.e., time, effort). Future research should also investigate more thoroughly how individual differences play a role here. This study used current food and mate seeking interest ratings to control for these likely very important moderators. Manipulating these factors may provide greater insight into whether this inhibition toward dual motivational opportunities has nonlinear components. Lastly, using sexual appeal ads was a strategic choice here; however, ads are targeted toward different demographic and psychographic groups. Using nonpersuasive messages in future studies will be important to generalize these results to circumstances representing motivational opportunity costs.

Theoretically, this project adds to the motivated cognition literature by identifying an anomalous finding and bridging a theoretical gap by engaging theory from outside communication. The findings presented here indicate that qualitatively different processing states can be achieved via content that is, under current communication theory, thought to be of similar motivational value. These findings also support a situated cognition perspective which advances that environmental constraints are very important in understanding how mediated cues will intervene upon and perturb behavior. These factors may ultimately change much of what we think we know about motivated cognition and related constructs.

Supplemental Material

FoodandSex_CR_R2_OnlineAppendix – Supplemental material for Primary Biological Motivators in Food Advertisements: Energy Density and Sexual Appeals Compete for Appetitive Motivational Activation

Supplemental material, FoodandSex_CR_R2_OnlineAppendix for Primary Biological Motivators in Food Advertisements: Energy Density and Sexual Appeals Compete for Appetitive Motivational Activation by Rachel L. Bailey, Jiawei Liu and Tianjiao Wang in Communication Research

Footnotes

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

Notes

ORCID iD

Rachel L. Bailey

Supplemental Material

Supplemental material for this article is available online.

Author Biographies

Rachel L. Bailey (PhD Indiana University, 2014) is an assistant professor at Florida State University. Her research program seeks to explicate complex human interactions with and via media and is rooted in biological and evolutionary perspectives including embodied, situated cognition and motivated cognition.

Jiawei Liu (PhD Washington State University, 2018) is a postdoctoral researcher in the College of Journalism and Communications at the University of Florida. Her research focuses on information processing and health communication.

Tianjiao (Grace) Wang (PhD Washington State University, 2017) is an assistant professor of Communication in the Slane College of Communications and Fine Arts at Bradley University. Her research aims to understand the dynamic interactions underlying emotion, motivational systems, and cognitive processing.

References

Bailey

R. L.

(2015). Processing food advertisements: Initial biological responses matter. Communication Monographs, 82, 163-178. doi:10.1080/03637751.2014.971417

Bailey

R. L.

(2016). Modern foraging: Presence of food and energy density influence motivational processing of food advertisements. Appetite, 107, 568-574. doi:10.1016/j.appet.2016.09.001

Bailey

R. L.

(2017). Influencing eating choices: Biological food cues in advertising and packaging alter trajectories of decision-making and behavior. Health Communication, 32, 1183-1191. doi:10.1080/10410236.201xf6.1214222

Bailey

R. L.

Wang

Liu

(2018, May). Applying optimal foraging to young adult decision-making after food advertising exposure. Paper presented at the annual meeting of the International Communication Association, Prague, Czech Republic.

Baumeister

R. F.

(2000). Gender differences in erotic plasticity: The female sex drive as socially flexible and responsive. Psychological Bulletin, 126, 347-374. doi:10.1037/0033-2909.126.3.347

Beckerman

(2010, September 23). Women selling food: A delicious, kinda disturbing history. Esquire. Retrieved from http://www.esquire.com/food-drink/a8551/sexy-food-advertisments-092310

Bradley

M. M.

Codispoti

Cuthbert

B. N.

Lang

P. J.

(2001). Emotion and motivation I: Defensive and appetitive reactions in picture processing. Emotion, 1, 276-298. doi:10.1037/1528-3542.1.3.276

Bradley

M. M.

Lang

P. J.

(2000). Measuring emotion: Behavior, feeling, and physiology. In Lane

R. D.

Nadel

(Eds.), Series in Affective Science. Cognitive neuroscience of emotion (pp. 242-276). New York, NY: Oxford University Press.

Cacioppo

J. T.

Berntson

G. G.

Norris

Gollan

J. K.

(2012). The evaluative space model. In Van Lange

Kruglanski

Higgins

E. T.

(Eds.), Handbook of theories of social psychology (Vol. 1, pp. 50-72). Thousand Oaks, CA: SAGE.

10.

Cacioppo

J. T.

Gardener

(1999). Emotion. Annual Review of Psychology, 50, 191-214.

11.

Chivers

Rieger

Latty

Bailey

(2004). A sex difference in specificity of sexual arousal. Psychological Science, 15, 736-744. doi:10.1111/j.0956-7976.2004.00750.x

12.

Drewnowski

(1997). Taste preferences and food intake. Annual Review of Nutrition, 17, 237-250. doi:10.1146/annurev.nutr.17.1.237

13.

Faul

Erdfelder

Lang

Buchner

(2007). G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior Research Methods, 39, 175-191. doi:10.3758/BF03193146

14.

Fridlund

A. J.

Cacioppo

J. T.

(1986). Guidelines for human electromyographic research. Psychophysiology, 23, 567-589. doi:10.1111/j.1469-8986.1986.tb00676.x

15.

Geuens

De Pelsmacker

(1998). Feelings evoked by warm, erotic, humorous or non-emotional print advertisements for alcoholic beverages. Journal of Marketing and Consumer Research, 16, 247-262.

16.

Gibson

J. J.

(1977). The theory of affordances. In Shaw

Brnasford

(Eds.), Perceiving, acting, and knowing: Toward an ecological psychology (pp. 67-82). Hillsdale, NJ: Lawrence Erlbaum.

17.

Harrar

Toepel

Murray

Spence

(2011). Food’s visually-perceived fat content and discrimination speed in an orthogonal spatial task. Experimental Brain Research, 214, 351-356. doi:10.1007/s00221-011-2833-6

18.

Jarvis

B. G.

(2014). MediaLab and DirectRT Research Software (v2014). New York, NY: Empirisoft.

19.

Keene

J. R.

Lang

(2016). Dynamic motivated processing of emotional trajectories in public service announcements. Communication Monographs, 83, 468-485. doi:10.1080/03637751.2016.1198040

20.

Killgore

W. D.

Young

A. D.

Femia

L. A.

Bogorodzki

Rogowska

Yurgelun-Todd

D. A.

(2003). Cortical and limbic activation during viewing of high- versus low-calorie foods. NeuroImage, 19, 1381-1394. doi:10.1016/S1053-8119(03)00191-5

21.

King

McClelland

Furnham

(2015). Sex really does sell: The recall of sexual and non-sexual television advertisements in sexual and non-sexual programmes. Applied Cognitive Psychology, 29, 210-216. doi:10.1002/acp.3095

22.

Kleiman

Trope

Amodio

D. M.

(2016). Cognitive control modulates attention to food cues: Support for the control readiness model of self-control. Brain & Cognition, 110, 94-101. doi:10.1016/j.bandc.2016.04.006

23.

Lang

(2006). Using the limited capacity model of motivated mediated message processing to design effective cancer communication messages. Journal of Communication, 56, S57-S80. doi:10.1111/j.1460-2466.2006.00283.x

24.

Lang

Bailey

R. L.

(2015). Understanding information selection and encoding from a dynamic, energy saving, evolved, embodied, embedded perspective. Human Communication Research, 41, 1-20. doi:10.1111/hcre.12040

25.

Lang

Park

Sanders-Jackson

Wilson

Wang

(2007). Cognition and emotion in TV message processing: How valence, arousing content, structural complexity, and information density affect the availability of cognitive resources. Media Psychology, 10, 317-338. doi:10.1080/15213260701532880

26.

Lang

Potter

R. F.

Bolls

(2009). Where psychophysiology meets the media: Taking the effects out of mass media research. In Bryant

Oliver

M. B.

(Eds.), Media effects: Advances in theory and research (3rd ed., pp. 185-206). New York, NY: Lawrence Erlbaum.

27.

Lang

Wise

Lee

Cai

X. M.

(2003). The effects of sexual appeals on physiological, cognitive, emotional, and attitudinal responses for product and alcohol billboard advertising. In Reichert

Lambiase

(Eds.), Sex in advertising: Perspectives on the erotic appeal. Mahwah, NJ: Lawrence Erlbaum.

28.

Lang

P. J.

Bradley

M. M.

Cuthbert

B. N.

(1997). Motivated attention: Affect, activation, and action. In Lang

P. J.

Simons

R. F.

Balaban

M. T.

(Eds.), Attention and orienting: Sensory and motivational processes (pp. 97-135). Hillsdale, NJ: Lawrence Erlbaum.

29.

Lang

P. J.

Greenwald

Bradley

M. M.

Hamm

A. O.

(1993). Looking at pictures: Evaluative, facial, visceral, and behavioral responses. Psychophysiology, 30, 261-273. doi:10.1111/j.1469-8986.1993.tb03352.x

30.

Larsen

J. T.

Norris

C. J.

Cacioppo

J. T.

(2003). Effects of positive and negative affect on electromyographic activity over zygomaticus major and corrugator supercilii. Psychophysiology, 40, 776-785. doi:10.1111/1469-8986.00078

31.

Lawrence

N. S.

Hinton

E. C.

Parkinson

J. A.

Lawrence

A. D.

(2012). Nucleus accumbens response to food cues predicts subsequent snack consumption in women and increased body mass index in those with reduced self-control. NeuroImage, 63, 415-422. doi:10.1016/j.neuroimage.2012.06.070

32.

Lee

Lang

(2015). Redefining media content and structure in terms of available resources: Toward a dynamic human centric theory of communication. Communication Research, 42, 599-625. doi:10.1177/0093650213488416

33.

Leka

McClelland

Furnham

(2013). Memory for sexual and non-sexual television commercials as a function of viewing context and viewer gender. Applied Cognitive Psychology, 27, 584-592. doi:10.1002/acp.2939

34.

Leshner

Bolls

Thomas

(2009). Scare’em or disgust’em: The effects of graphic health promotion messages. Health Communication, 24, 447-458. doi:10.1080/10410230903023493

35.

Potter

Bolls

P. D.

(2012). Psychophysiological measurement and meaning: Cognitive and emotional processing of media. New York, NY: Routledge.

36.

Pyke

G. H.

Pullium

H. R.

Charnov

E. L.

(1977). Optimal foraging: A selective review of theory and tests. The Quarterly Review of Biology, 52, 137-154. doi:10.1016/j.cub.2008.02.072

37.

Reichert

Heckler

S. E.

Jackson

(2001). The effects of sexual social marketing appeals on cognitive processing and persuasion. Journal of Advertising, 30, 13-27. doi:10.1080/00913367.2001.10673628

38.

Reppucci

C.J.

Petrovich

G.D.

(2012). Learned food-cue stimulates persistent feeding in sated rats. Appetite, 59, 437-447.

39.

Schoener

T. W.

(1971). Theory of feeding strategies. Annual Review of Ecology and Systematics, 11, 369-404. doi:10.1146/annurev.es.02.110171.002101

40.

Sparks

J. V.

Lang

(2015). Mechanisms underlying the effects of sexy and humorous content in advertisements. Communication Monographs, 82, 134-162. doi:10.1080/03637751.2014.976

41.

Stoeckel

L. E.

Cox

J. E.

Cook

E. W.

III. . Weller

R. E.

(2007). Motivational state modulates the hedonic value of food images differently in men and women. Appetite, 48, 139-144. doi:10.1016/j.appet.2006.07.079

42.

Thayer

J. F.

Friedman

B. H.

(1997). The heart of anxiety: A dynamical systems approach. In Vingerhoest

(Ed.), The (non)expression of emotions in health and disease. Amsterdam: Springer Verlag.

43.

Thayer

J. F.

Lane

R. D.

(2000). A model of neurovisceral integration in emotion regulation and dysregulation. Journal of Affective Disorders, 61, 201-216. doi:10.1016/S0165-0327(00)00338-4

44.

Toepel

Knebel

J. F.

Hudry

le Coutre

Murray

M. M.

(2009). The brain tracks the energetic value in food images. NeuroImage, 44, 967-974. doi:10.1016/j.neuroimage.2008.10.0

45.

Trivers

(1972). Parental investment and sexual selection. In Cambpell

(Ed.), Sexual selection & the descent of man (pp. 136-179). Chicago, IL: Aldine.

46.

Wang

Morey

A. C.

Srivastava

(2014). Motivated selective attention during political ad processing: The dynamic interplay between emotional ad content and candidate evaluation. Communication Research, 41, 119-156. doi:10.1177/0093650212441793

47.

Wang

Solloway

Tchernev

J. M.

Barker

(2012). Dynamic motivational processing of antimarijuana messages: Coactivation begets attention. Human Communication Research, 38, 485-509. doi:10.1111/j.1468-2958.2012.01431.x

48.

Wasserman

Crockett

L. J.

Hoffman

(2017). Reward seeking and cognitive control: Using the dual systems model to predict adolescent sexual behavior. Journal of Research on Adolescence, 27, 907-913. doi:10.1111/jora.123

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