Differential responses to ethical vegetarian appeals: Exploring the role of traits, beliefs, and motives.

OBJECTIVE: This research examines differential responses to ethical vegetarian appeals as a fuction of individuals' personalities. BACKGROUND: Ethical vegetarian appeals are persuasive messages promoting the adoption of a plant-based diet on moral grounds. Individuals may vary in their receptivity to such appeals, depending on their morally relevant traits (e.g., agreeableness), beliefs (e.g., speciesism), and motives (e.g., concerns about animal welfare). METHODS: We explored (Study 1, N = 907) and then attempted to confirm (Study 2, N = 980) differential responses to three vegetarian appeals-two highlighting moral concerns (animal welfare, the environment) and a third focusing on individual health (control condition). RESULTS: Both studies revealed several differential effects of our vegetarian appeals on the perceived effectiveness of the appeal and resultant intentions to reduce meat consumption. These mostly consisted of differences in receptivity to appeals focused on animal welfare. However, only one such effect observed in Study 1 was clearly replicated in Study 2: People who more strongly believed that eating meat was "normal" rated the vegetarian appeals focused on animal welfare as less effective. CONCLUSION: Ethical vegetarian appeals may elicit different responses from different people, particularly those focused on animal welfare, depending on how normative one believes meat-eating to be. Such insights can inform behavior change efforts in this area.

Evaluating the effectiveness of vegetarian appeals in daily life: Comparing positive and negative imagery, and gauging differential responses.

Persuasive appeals designed to reduce meat consumption often employ graphic images of the harms perpetuated by eating meat (e.g., cruel factory farming practices). However, because people are motivated to see themselves as moral, appeals that highlight omnivores' moral failings might be resisted or even backfire. Furthermore, individuals differ in ways that may influence their motivations and attitudes toward animals and meat-eating, and their responses to these appeals. Thus, in a two-week intervention study (N = 427), we compared effects of two vegetarian appeals-one employing graphic negative imagery (footage of factory farming cruelty), the other employing positive imagery (footage from farmed animal sanctuaries)-on daily meat consumption and related affects and cognitions. We also examined several personality traits and other individual differences that may confer differential effects of these appeals. Although neither appeal significantly reduced meat consumption, both the positive and negative appeal increased intentions to eat less meat, and led to more negative affect and cognition when eating meat. Moreover, several individual difference variables moderated the effects of these appeals on actual and intended meat consumption. Findings are discussed in relation to the difficulty of changing morally troublesome behaviour, and the use of graphic appeals despite their unclear impact on behaviour.

Does openness/intellect predict sensitivity to the reward value of information?

A recent theory proposes that the personality trait openness/intellect is underpinned by differential sensitivity to the reward value of information. This theory draws on evidence that midbrain dopamine neurons respond to unpredicted information gain, mirroring their responses to unpredicted primary rewards. Using a choice task modelled on this seminal work (Experiment 1, N = 139, 69% female), we examined the relation between openness/intellect and willingness to pay for non-instrumental information (i.e., information with no secondary utility). We also assessed whether any such relation was moderated by the dopamine D2 receptor antagonist sulpiride (Experiment 2, N = 164, 100% male). Unexpectedly, most measures of openness/intellect were unrelated to costly information preference in both experiments, and some predicted a decreased willingness to incur a cost for information. In Experiment 2, this cost-dependent association between openness/intellect and information valuation appeared in the placebo condition but not under sulpiride. In addition, participants were more willing to pay for moderately costly information under sulpiride compared to placebo, consistent with a dopaminergic basis to information valuation. Potential refinements to the information valuation theory of openness/intellect are discussed in the light of these and other emerging findings.

Who gives a veg? Relations between personality and Vegetarianism/Veganism.

With rates of vegetarianism and veganism (i.e., veg*nism) rising around the world, a growing body of research has begun to explore psychological characteristics that distinguish vegetarians and vegans from omnivores. However, relatively few studies have examined how veg*nism is related to differences in basic personality traits such as the "Big Five", with those that have tending to yield conflicting results. Moreover, none of these studies have examined personality at the lower levels of the personality trait hierarchy (i.e., aspects and facets of the Big Five). Thus, we sought to clarify how personality traits are related to veg*nism. In Study 1, comprising two samples (S1a: N = 797, S1b: N = 1534), participants were categorised as Veg*n vs Restricted-omnivore vs Omnivore, and completed personality questionnaires at the domain and aspect levels of the Big Five. In Study 2, participants (N = 562) completed both categorical and continuous measures of veg*nism, along with personality questionnaires at the domain, aspect, and facet levels. Across both studies, we found that people who scored higher on traits within the openness/intellect and agreeableness domains most consistently reported higher levels of veg*nism. Patterns in the data also suggested that the relation between personality and veg*nism might depend on the way veg*nism is measured. Theoretical and practical implications of these findings are discussed.