Paul Rozin

Negativity Bias, Negativity Dominance, and Contagion

We hypothesize that there is a general bias, based on both innatepredispositions and experience, in animals and humans, to give greater weight to negative entities (e.g., events, objects, personal traits). This is manifested in 4 ways: (a) negative potency (negative entities are stronger than the equivalent positive entities), (b) steeper negative gradients (the negativity of negative events grows more rapidly with approach to them in space or time than does the positivity of positive events, (c) negativity dominance (combinations of negative and positive entities yield evaluations that are more negative than the algebraic sum of individual subjective valences would predict), and (d) negative differentiation (negative entities are more varied, yield more complex conceptual representations, and engage a wider response repertoire). We review evidence for this taxonomy, with emphasis on negativity dominance, including literary, historical, religious, and cultural sources, as well as the psychological literatures on learning, attention, impression formation, contagion, moral judgment, development, and memory. We then consider a variety of theoretical accounts for negativity bias. We suggest that 1 feature of negative events that make them dominant is that negative entities are more contagious than positive entities.

Individual differences in sensitivity to disgust: A scale sampling seven domains of disgust elicitors

We describe the development of a reliable measure of individual differences in disgust sensitivity. The 32-item Disgust Scale includes 2 true-false and 2 disgust-rating items for each of 7 domains of disgust elicitors (food, animals, body products, sex, body envelope violations, death, and hygiene) and for a domain of magical thinking (via similarity and contagion) that cuts across the 7 domains of elicitors. Correlations with other scales provide initial evidence of convergent and discriminant validity: the Disgust Scale correlates moderately with Sensation Seeking (r= - 0.46) and with Fear of Death (r= 0.39), correlates weakly with Neuroticism (r = 0.23) and Psychoticism (r= - 0.25), and correlates negligibly with Self-Monitoring and the Eysenck Personality Questionnaire Extraversion and Lie scales. Females score higher than males on the Disgust Scale. We suggest that the 7 domains of disgust elicitors all have in common that they remind us of our animality and, especially, of our mortality. Thus we see disgust as a defensive emotion that maintains and emphasizes the line between human and animal.

The CAD triad hypothesis: a mapping between three moral emotions (contempt, anger, disgust) and three moral codes (community, autonomy, divinity).

It is proposed that 3 emotions--contempt, anger, and disgust--are typically elicited, across cultures, by violations of 3 moral codes proposed by R. A. Shweder and his colleagues (R. A. Shweder, N. C. Much, M. Mahapatra, & L. Park, 1997). The proposed alignment links anger to autonomy (individual rights violations), contempt to community (violation of communal codes including hierarchy), and disgust to divinity (violations of purity-sanctity). This is the CAD triad hypothesis. Students in the United States and Japan were presented with descriptions of situations that involve 1 of the types of moral violations and asked to assign either an appropriate facial expression (from a set of 6) or an appropriate word (contempt, anger, disgust, or their translations). Results generally supported the CAD triad hypothesis. Results were further confirmed by analysis of facial expressions actually made by Americans to the descriptions of these situations.

The Selection of Foods by Rats, Humans, and Other Animals

Publisher Summary This chapter discusses the selection of food by rats, humans, and other animals, and focuses on the complex problems, especially in food recognition and choice, in the omnivores or generalists. Food selection implies food ingestion. Food ingestion implies the presence of food. Therefore, background for the study of food selection includes the food search process: search images and search mechanisms for finding appropriate food stimuli in the environment. Honey bees provide fine examples of a highly developed food search system. Food selection also implies the ability to obtain or capture food, and to assimilate it, for which many often exotic mechanisms have been evolved. Given the presence of potential food, ingestion then usually depends on an internal state or detector indicating a “need” for the particular food or class of foods, and recognition of the potential food as food. Omnivores, such as rats and humans, faced with an enormous number of potential foods, must choose wisely. They are always in danger of eating something harmful or eating too much of a good thing. Although there are some helpful internal mechanisms, such as poison detoxification, nutrient biosynthesis, and nutrient storage, the major share of the burden for maintaining nutritional balance must out of necessity come from incorporation of appropriate nutrients in the environment and, hence, behavior. The most striking parallel between human and rat feeding is in the neophobia seen in both. The chapter discusses the multiple determinants of food selection in man that are divided into biological factors and effects of individual experience, on one hand, and cultural influences, on the other.

Body image, attitudes to weight, and misperceptions of figure preferences of the opposite sex: a comparison of men and women in two generations.

This study explores some possible causes of the recent increase in dieting and eating disorders among American women. Measures on body image, attitudes to eating and weight, and eating behaviors were collected from male (sons) and female (daughters) college students and their biological parents. All groups but the sons considered their current body shape to be heavier than their ideal. Mothers and daughters believed that men (of their own generation) prefer much thinner women than these men actually prefer. Mothers and daughters both showed great concern about weight and eating. Although fathers resembled mothers and daughters in their perception of being overweight, they were more similar to their sons in being relatively unconcerned about weight and eating. Hence, the major factor in concern about weight is sex rather than generation or discrepancy between perception of current and ideal body shape.

Moralization and Becoming a Vegetarian: The Transformation of Preferences Into Values and the Recruitment of Disgust:

We describe a rather common process that we call moralization, in which objects or activities that were previously morally neutral acquire a moral component. Moralization converts preferences into values, and in doing so influences cross-generational transmission (because values are passed more effectively in families than are preferences), increases the likelihood of internalization, invokes greater emotional response, and mobilizes the support of governmental and other cultural institutions. In recent decades, we claim, cigarette smoking in America has become moralized. We support our claims about some of the consequences of moralization with an analysis of differences between health and moral vegetarians. Compared with health vegetarians, moral vegetarians find meat more disgusting, offer more reasons in support of their meat avoidance, and avoid a wider range of animal foods. However, contrary to our prediction, liking for meat is about the same in moral and health vegetarians.

Chocolate craving and liking.

Liking and craving for chocolate and related substances were surveyed in a sample of University of Pennsylvania undergraduates (n = 249) and their parents (n = 319). Chocolate was highly liked in all groups, with a stronger liking by females. Chocolate is the most craved food among females, and is craved by almost half of the female sample (in both age groups). Although this craving is related to a sweet craving, it cannot be accounted for as a craving for sweets. About half of the female cravers show a very well defined craving peak for chocolate in the perimenstrual period, beginning from a few days before the onset of menses and extending into the first few days of menses. There is not a significant relation in chocolate craving or liking between parents and their children. The current motivation for chocolate preference seems to be primarily, if not entirely, sensory. Liking for chocolate correlates significantly with liking for sweets and white chocolate. The liking for the sensory properties could originate in innate or acquired liking based on the sweetness, texture and aroma of chocolate, or it could be based in part on interactions between the postingestional effects of chocolate and a persons state (e.g., mood, hormone levels). Based on correlational data, we find little evidence for a relation between addiction to chocolate or the pharmacological (e.g., xanthine-based) effects of chocolate and the liking for chocolate.

Quality of acquired responses to tastes by Rattus norvegicus depends on type of associated discomfort.

Rats were trained to avoid a sugar solution through pairing with LiCl toxicosis (upper gastrointestinal tract discomfort), shock (peripheral pain), or high levels of lactose (lower gastrointestinal tract discomfort). Among animals matched for strength of avoidance of the sugar solution, only the LiCl group showed orofacial responses (e.g., gaping) indicative of distaste; the other groups continued to show positive orofacial responses to the sugar solution. These results, in conjunction with recent results on humans, are interpreted to represent a distinction between food rejection based primarily on unpalatability (distaste) and food rejection based primarily on anticipated negative consequences of ingestion (danger). The results also support the hypothesis that upper gastrointestinal distress (most probably nausea) plays a special role in negative palatability shifts (acquired distastes). These results have implications for the understanding of predispositions in learning and suggest important differences in the quality (readout) of different types of associations. Prior research, by relying on intake measures alone, was insensitive to the differences revealed here by monitoring a wider range of responses.

Varieties of disgust faces and the structure of disgust.

In 3 facial expression identification studies, college students matched a variety of disgust faces to verbally described eliciting situations. The faces depicted specific muscle action movements in accordance with P. Ekman and W. V. Friesens (1978) Facial Action Coding System. The nose wrinkle is associated with either irritating or offensive smells and, to some extent, bad tastes. Gape and tongue extrusion are associated primarily with what we call core or food-offense disgust and also oral irritation. The broader range of disgust elicitors, including stimuli that remind humans of their animal origins (e.g., body boundary violations, inappropriate sex, poor hygiene, and death), a variety of aversive interpersonal contacts, and certain moral offenses are associated primarily with the raised upper lip. The results support a theory of disgust that posits its origin as a response to bad tastes and maps its evolution onto a moral emotion.

Preference for natural: instrumental and ideational/moral motivations, and the contrast between foods and medicines

Preference for natural refers to the fact that in a number of domains, especially food, people prefer natural entities to those which have been produced with human intervention. Two studies with undergraduate students and representative American adults indicate that the preference for natural is substantial, and stronger for foods than for medicines. Although healthfulness is often given as a reason for preferring natural foods, even when healthfulness or effectiveness (for medicines) of the natural and artificial exemplars is specified as equivalent, the great majority of people who demonstrate a preference for natural continue to prefer natural. In addition, when the natural and artificial exemplars are specified to be chemically identical, a majority of people who prefer natural continue to prefer it. This suggests that a substantial part of the motivation for preferring natural is ideational (moral or aesthetic), as opposed to instrumental (healthiness/effectiveness or superior sensory properties).