Disgust and the Politics of Sex: Exposure to a Disgusting Odorant Increases Politically Conservative Views on Sex and Decreases Support for Gay Marriage

Disgust has been implicated as a potential causal agent underlying socio-political attitudes and behaviors. Several recent studies have suggested that pathogen disgust may be a causal mechanism underlying social conservatism. However, the specificity of this effect is still in question. The present study tested the effects of disgust on a range of policy preferences to clarify whether disgust is generally implicated in political conservatism across public policy attitudes or is uniquely related to specific content domains. Self-reported socio-political attitudes were compared between participants in two experimental conditions: 1) an odorless control condition, and 2) a disgusting odor condition. In keeping with previous research, the present study showed that exposure to a disgusting odor increased endorsement of socially conservative attitudes related to sexuality. In particular, there was a strong and consistent link between induced disgust and less support for gay marriage.     

Parasite primes make foreign-accented English sound more distant to people who are disgusted by pathogens (but not by sex or morality)

To avoid disease, people should maintain close ties with ingroup members but maintain distance from outgroup members who possess novel pathogens. Consistent with this disease-avoidance hypothesis, pathogenic stimuli, as well as increased personal vulnerability to disease, are associated with xenophobic and ethnocentric attitudes. Researchers assume that this disease-avoidance process is an automatic emotional response that compels negative attitudes and behavioral avoidance. However, when outgroup contact can represent fitness costs or benefits, and when group membership is an uncertain cue to infection risk, it becomes a fitness advantage for a social perceiver to track group membership and thus infection risk. Given that accents can be a cue to group membership, we predicted that the perception of linguistic similarity to ingroup speakers and dissimilarity from outgroup speakers would increase with individual differences in pathogen disgust, and that this association would be most apparent when threat of disease was salient. This hypothesis was confirmed in two experiments. Further, the mechanism was domain specific—disgust due to sexual acts and moral violations did not moderate perceived linguistic distance. The disease-avoidance mechanism is not just an automatic disgust-based reaction; it also operates through the cognitive appraisal of social distance.     

Disease avoidance as a functional basis for stigmatization

Stigmatization is characterized by chronic social and physical avoidance of a person(s) by other people. Infectious disease may produce an apparently similar form of isolation-disease avoidance-but on symptom remission this often abates. We propose that many forms of stigmatization reflect the activation of this disease-avoidance system, which is prone to respond to visible signs and labels that connote disease, irrespective of their accuracy. A model of this system is presented, which includes an emotional component, whereby visible disease cues directly activate disgust and contamination, motivating avoidance, and a cognitive component, whereby disease labels bring to mind disease cues, indirectly activating disgust and contamination. The unique predictions of this model are then examined, notably that people who are stigmatized evoke disgust and are contaminating. That animals too show avoidance of diseased conspecifics, and that disease-related stigma targets are avoided in most cultures, also supports this evolutionary account. The more general implications of this approach are then examined, notably how it can be used to good (e.g. improving hygiene) or bad (e.g. racial vilification) ends, by yoking particular labels with cues that connote disease and disgust. This broadening of the model allows for stigmatization of groups with little apparent connection to disease.     

Social neuroscience of disgust

Disgust can be thought of as an affective system that has evolved to detect signs of pathogens, parasite and toxins as well as to stimulate behaviors that reduce the risk of their acquisition. Disgust incorporates social cognitive mechanisms to regulate exposure to and, or anticipate and avoid exposure to pathogens and toxins. Social cognition entails the acquisition of social information about others (ie, social recognition) and from others (ie, social learning). This involves recognizing and assessing other individuals and the pathogen/parasite/contamination/toxin threat they pose and deciding about when and how to interact with and, or avoid them. Social cognition provides a frame‐work for examining the expression of disgust and the associated neurobiological mechanisms. Here, we briefly consider the relations between social cognition and pathogen/parasite/toxin avoidance behaviors. We briefly discuss aspects of: (1) the odor mediated social recognition of actual and potentially infected individuals and the impact of parasite/pathogen threat on disgust mate and social partner choice; (2) the roles of “out‐groups” (strangers, unfamiliar individuals) and “in‐groups” (familiar individuals) in the expression of disgust and pathogen avoidance behaviors; (3) individual and social learning of disgust and empathy for disgust; (4) toxin elicited disgust and anticipatory disgust; (5) the neurobiological mechanisms, and in particular the roles of the nonapeptide, oxytocin and estrogenic mechanism associated with social cognition and the expression of disgust. These findings on the social neuroscience of disgust have a direct bearing on our understanding of the roles of disgust in shaping human and nonhuman social behavior.     

Social learning influences the preferences of domestic hens for novel food

It has been argued that social learning helps animals either avoid noxious substances or identify food items, but evidence suggests that avian social learning is fundamentally different from that of mammals. In two experiments, we investigated whether the preferences of domestic hens, Gallus g. domesticus, for novel food were influenced by observing the feeding behaviour of conspecifics. In experiment 1, we attempted to confirm that birds can develop socially learnt aversions to unpalatable foods. Despite demonstrators showing a highly visible ‘disgust reaction’ after eating unpalatable coloured food, observers did not develop aversions to similarly coloured food. In experiment 2, we aimed to determine whether preferences for palatable food were socially learnt, and whether the extent of a demonstrator's preference for novel food affected the magnitude of the observer's socially learned preference. Demonstrators ate coloured food of standard or high palatability, or did not peck food at all. When the demonstrators pecked more frequently or fed more quickly from the food, the observers consumed a greater proportion of food of the same colour; however, this was only when the food was red, not green. We argue this indicates an unlearned aversion to red food, overcome by social learning of the food being highly palatable. The results provide no evidence that adult hens learn aversions through observing disgust reactions, but show that hens are sensitive to the extent of demonstrator preferences for palatable food. The data do not support the hypothesis that avian social learning is fundamentally different from that of mammals. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.     

Disgust sensitivity predicts sociosexuality across cultures

Restricted sociosexuality has been linked to sexual disgust, suggesting that decreasing sexual behavior may be a pathogen avoidance technique. Using the behavioral immune system framework, which posits that humans experience disgust after exposure to pathogen cues, we replicate and expand on previous studies by analyzing the influence of three domains of disgust (sexual, moral, pathogen) on psychological (desire and attitude) and behavioral domains of sociosexuality (SOI) in four diverse samples: American university students (n = 155), Salvadoran community members (n = 98), a global online sample (n = 359), and a four-country online sample (US, India, Italy, and Brazil; n = 822) collected during the SARS-CoV-2 pandemic. In contrast with previous studies, we account for shared variance in sexual, pathogen, and moral disgust by entering all three in a multiple regression to predict composite SOI. In both large samples, sexual disgust and pathogen disgust had opposing effects on composite SOI; that is, higher sexual disgust and lower pathogen disgust were associated with more restricted composite SOI. Additionally, we constructed a multi-group structural equation model (SEM) to determine the impact of each domain of disgust on each domain of SOI across all our samples simultaneously, while controlling for age and sex. Within this model we also assessed how the psychological domains of SOI – attitude and desire – mediate the relationship between disgust and sociosexual behavior. Pathogen disgust positively predicted SOI attitude and desire, but not behavior, consistently across all groups. SOI behavior was only predicted by pathogen disgust when mediated by SOI attitude, again across all groups, suggesting that behavior seems to be driven largely by the psychological facets of SOI. We discuss these findings in light of the behavioral immune system and the bet-hedging hypothesis, which make opposing predictions on the relationship between infection risk and sexual behavior.     

Great Apes Do Not Learn Novel Tool Use Easily: Conservatism,Functional Fixedness,or Cultural Influence?

Animal culture has been of interest for decades but the concept remains controversial. Many researchers feel that animal behavior should not be granted the label “culture” because the latter includes more than “simple” behavioral variation. In recent years, the study of animal culture has been concerned mainly with social learning mechanisms, often claimed to be human specific, which led to the uniqueness of human culture. In addition, failure to innovate novel cultural behavior as often as humans is usually explained by psychological mechanisms presented as more parsimonious, such as conservatism or functional fixedness. However, it is unclear how cognitively complex these mechanisms are in the first place. Here, I analyze recent data obtained with wild chimpanzees (Pan troglodytes schweinfurthii) and wild-born orangutans (Pongo abelii) using the honey-trap experiment, in which individuals must devise a solution to reach inaccessible honey. I compare behavior of apes that developed a tool-based solution in the task with those that did not, and test whether conservatism and functional fixedness can explain individual variation in ape behavior. I find evidence of conservatism, with apes relying on their existing knowledge, and evidence of functional fixedness, with this knowledge potentially preventing them from innovating. However, the apes showed large intraspecific variability. I discuss the two mechanisms through a representational perspective to tackle their cognitive complexity. Understanding how conservatism and functional fixedness interact with ape cultural knowledge to limit innovation of novel tool use appears necessary to understand the full extent of ape cultures and how they compare to human cultures.     

The neurobiology of pair bond formation,bond disruption,and social buffering

Enduring social bonds play an essential role in human society. These bonds positively affect psychological, physiological, and behavioral functions. Here, we review the recent literature on the neurobiology, particularly the role of oxytocin and dopamine, of pair bond formation, bond disruption, and social buffering effects on stress responses, from studies utilizing the socially monogamous prairie vole (Microtus ochrogaster).     

Emotion Regulation as the Foundation of Political Attitudes: Does Reappraisal Decrease Support for Conservative Policies?

Cognitive scientists, behavior geneticists, and political scientists have identified several ways in which emotions influence political attitudes, and psychologists have shown that emotion regulation can have an important causal effect on physiology, cognition, and subjective experience. However, no work to date explores the possibility that emotion regulation may shape political ideology and attitudes toward policies. Here, we conduct four studies that investigate the role of a particular emotion regulation strategy – reappraisal in particular. Two observational studies show that individual differences in emotion regulation styles predict variation in political orientations and support for conservative policies. In the third study, we experimentally induce disgust as the target emotion to be regulated and show that use of reappraisal reduces the experience of disgust, thereby decreasing moral concerns associated with conservatism. In the final experimental study, we show that use of reappraisal successfully attenuates the relationship between trait-level disgust sensitivity and support for conservative policies. Our findings provide the first evidence of a critical link between emotion regulation and political attitudes.     

Social Network Ties and Inflammation in U.S. Adults with Cancer

The growing evidence linking social connectedness and chronic diseases such as cancer calls for a better understanding of the underlying biophysiological mechanisms. This study assessed the associations between social network ties and multiple measures of inflammation in a nationally representative sample of adults with a history of cancer (N = 1,075) from the National Health and Nutrition Examination Survey III (1988–94). Individuals with lower social network index (SNI) scores showed significantly greater inflammation marked by C-reactive protein and fibrinogen, adjusting for age and sex. Compared to fully socially integrated individuals (SNI = 4), those who were more socially isolated or had a SNI score of 3 or less exhibited increasingly elevated inflammation burdens. Specifically, the age- and sex-adjusted odds ratios (95%CI) for SNIs of 3, 2, and 0–1 were 1.49 (1.08, 2.06), 1.69 (1.21, 2.36), and 2.35 (1.62, 3.40), respectively (p < .001). Adjusting for other covariates attenuated these associations. The SNI gradients in the risks of inflammation were particularly salient for the lower socioeconomic status groups and remained significant after adjusting for other social, health behavioral, and illness factors. This study provided initial insights into the immunological pathways by which social connections are related to morbidity and mortality outcomes of cancer in particular and aging-related diseases in general.     

Regulation of PDF receptor signaling controlling daily locomotor rhythms in Drosophila

Each day and in conjunction with ambient daylight conditions, neuropeptide PDF regulates the phase and amplitude of locomotor activity rhythms in Drosophila through its receptor, PDFR, a Family B G protein-coupled receptor (GPCR). We studied the in vivo process by which PDFR signaling turns off, by converting as many as half of the 28 potential sites of phosphorylation in its C terminal tail to a non-phosphorylatable residue (alanine). We report that many such sites are conserved evolutionarily, and their conversion creates a specific behavioral syndrome opposite to loss-of-function phenotypes previously described for pdfr. That syndrome includes increases in the amplitudes of both Morning and Evening behavioral peaks, as well as multi-hour delays of the Evening phase. The precise behavioral effects were dependent on day-length, and most effects mapped to conversion of only a few, specific serine residues near the very end of the protein and specific to its A isoform. Behavioral phase delays of the Evening activity under entraining conditions predicted the phase of activity cycles under constant darkness. The behavioral phenotypes produced by the most severe PDFR variant were ligand-dependent in vivo, and not a consequence of changes to their pharmacological properties, nor of changes in their surface expression, as measured in vitro. The mechanisms underlying termination of PDFR signaling are complex, subject to regulation that is modified by season, and central to a better understanding of the peptidergic modulation of behavior.     

Disease avoidance and ethnocentrism: the effects of disease vulnerability and disgust sensitivity on intergroup attitudes

Extending a model relating xenophobia to disease avoidance [Faulkner, J., Schaller, M., Park, J. H., & Duncan, L. A. (2004). Evolved disease-avoidance mechanisms and contemporary xenophobic attitudes. Group Processes & Intergroup Relations, 7(4), 333–353.], we argue that both inter- and intragroup attitudes can be understood in terms of the costs and benefits of interacting with the in-group versus out-groups. In ancestral environments, interaction with members of the in-group will generally have posed less risk of disease transmission than interaction with members of an out-group, as individuals will have possessed antibodies to many of the pathogens present in the former, in contrast to those prevalent among the latter. Moreover, because coalitions are more likely among in-group members, the in-group would have been a potential source of aid in the event of debilitating illness. We conducted two online studies exploring the relationship between disease threat and intergroup attitudes. Study 1 found that ethnocentric attitudes increase as a function of perceived disease vulnerability. Study 2 found that in-group attraction increases as a function of disgust sensitivity, both when measured as an individual difference variable and when experimentally primed. We discuss these results with attention to the relationships among disease salience, out-group negativity, and in-group attraction.     

Species-specific patterns of nonapeptide brain gene expression relative to pair-bonding behavior in grouping and non-grouping cichlids

Comparative studies have revealed that vasopressin–oxytocin pathways are associated with both pair bonding and grouping behavior. However, the relationship between pair bonding and grouping behavior remains unclear. In this study, our aim was to identify whether two species that differ in grouping behavior display a corresponding difference in their pair bonds, and in the underlying vasopressin–oxytocin hormonal pathways. Using two species of cichlid fishes, the highly social Neolamprologus pulcher and the non-social Telmatochromis temporalis, we measured proximity of pairs during pair bond formation, and then measured social behaviors (proximity, aggression, submission, affiliation) and brain gene expression of isotocin and arginine vasotocin (the teleost homologues of oxytocin and vasopressin, respectively), as well as their receptors, after a temporary separation and subsequent reunion of the bonded pairs. Pairs of the social species spent more time in close proximity relative to the non-social species. Rates of aggression increased in both species following the separation and reunion treatment, relative to controls that were not separated. Overall, whole brain expression of isotocin was higher in the social species relative to the non-social species, and correlated with proximity, submission, and affiliation, but only in the social species. Our results suggest that both a social and a non-social cichlid species have similar behavioral responses to a temporary separation from a mate, and we found no difference in the brain gene expression of measured hormones and receptors based on our separation–reunion treatment. However, our results highlight the importance of isotocin in mediating submissive and affiliative behaviors in cichlid fishes, and demonstrate that isotocin has species-specific correlations with socially relevant behaviors.     

New insights into the taxonomy and phylogeny of social voles inferred from mitochondrial cytochrome b sequences

We sequenced the entire cytochrome b gene in Microtus paradoxus from Turkmenistan and Microtus socialis from Crimea and Kalmykia. Phylogenetic relationships among social voles were reconstructed by the inclusion into analyses of a further 23 published haplotypes belonging to six species. The two probabilistic methods which were used in phylogenetic analyses, the Bayesian inference and Maximum Likelihood, yielded very similar results. Both trees showed two highly divergent lineages which were further subdivided into seven species. The socialis lineage encompassed four species (M. socialis, M. irani, M. anatolicus, and M. paradoxus), and the remaining three species clustered into the guentheri lineage (M. guentheri, M. hartingi, M. dogramacii). The ranges for nucleotide divergences between seven species of social voles (4.95–9.28% and 4.18–8.81% for mean and net divergences, respectively) mainly exceeded 4.3%, which is frequently regarded as the conservative cut-off between sibling species in the specious genus Microtus.     

Behavioral and physiological plasticity: Rapid changes during social ascent in an African cichlid fish

In many vertebrates, reproduction is regulated by social interactions in which dominant males control access to females and food. Subordinate males that displace dominant individuals must rapidly adopt behavioral and physiological traits of the higher rank to gain reproductive success. To understand the process of phenotypic plasticity during social ascent, we analyzed the temporal expression pattern of dominance behaviors and circulating androgen levels when socially-suppressed males of an African cichlid fish Astatotilapia burtoni ascended in status. These experiments tested a prediction of the ‘challenge hypothesis’ that, during periods of social instability, male androgen levels are higher than during socially stable times. We found that socially and reproductively suppressed males perform territorial and reproductive behaviors within minutes of an opportunity to ascend in status, and that animals switch from initial expression of territorial behaviors to more reproductive behaviors during territory establishment. Following this rapid response, social stability may be achieved within 1-3 days of social ascent. Consistent with predictions of the ‘challenge hypothesis’, circulating 11-ketotestosterone (11-KT) levels were elevated within 30 min following social opportunity, coincident with increased aggressive behavior. However, territorial behaviors and serum 11-KT levels were then dissociated by 72 h after social ascent, suggesting either rapid social stability and/or increased physiological potential for androgen production. This behavioral and physiological plasticity in male A. burtoni suggests that perception of social opportunity triggers a suite of quick changes to facilitate rapid transition towards reproductive success, and reveals important features of social ascent not previously recognized.     

Soybean molasses-based bioindicator system for monitoring sterilization process: Designing and performance evaluation

A novel cost-effective Bacillus atrophaeus Sterilization Bioindicator System (BIS) with a high quality and performance was developed from a soybean byproduct and compared with the commercial BIS. It was composed of recovery medium and dry-fermented spores with sand as the support. The BIS was developed and optimized using a sequential experimental design strategy. The recovery medium contained soluble starch (1.0 g/L), soybean molasses (30.0 g/L), tryptone (40.0 g/L), and bromothymol blue (0.02 g/L) at pH 8.5. The solid-state fermentation conditions of the bioreactor and environmental humidity had no significant effects on the spore yield and dry-heat resistance. The only substrate mineral that showed a positive effect was Mn²⁺, allowing Mg²⁺, K⁺, and Ca²⁺ to be eliminated from the formulation. Validation of optimized medium indicated D _160°C = 6.8±1.0 min (3.6 min more than the minimum) and spore yield = 2.3 ± 0.5 × 10⁹ CFU/g dry sand (10,000 × initial values). BIS performance resulted in D _160°C = 6.6 ± 0.1 min. Sporulation and germination kinetics allowed the sporulation process to be reduced to three days, and the growth of heat-damaged spores was sufficient to achieve visual identification of a non-sterile BIS within 21 h. Process economics was a minimum of 23.9%, and process cycle time was reduced from 29 to 15 days. The new BIS parameters demonstrated compliance to all regulatory requirements. No studies have yet described a BIS production from soybean molasses.     

Social plasticity in non-territorial male African cichlid fish <Emphasis Type="Italic">Astatotilapia burtoni</Emphasis>

The African cichlid fish Astatotilapia burtoni represents a valuable model system for studies of social decision-making due to its socially mediated phenotypic plasticity. The males reversibly transition in social status from reproductively dominant and territorial (DOM) to submissive and non-territorial (SUB). Males are traditionally categorized into these two behavioral phenotypes by observational scoring. There is evidence, however, that this dichotomous categorization might not capture the behavioral plasticity displayed by individuals transitioning between SUB and DOM status. To test this concept, we used focal observations of intrasexual conflict behavior in fish communities combined with a modified analysis of the ethogram typically used in A. burtoni. Results revealed a cluster of males close to the crossover point between SUB and DOM status as defined by the traditional dominance index. These intermediate males showed the highest frequency of intrasexual conflict behaviors, distinct behavioral responses to threats, and body pigment signaling displays that distinguish them from prototypical SUBs and DOMs. As such, our results provide a noninvasive behavioral metric to categorize A. burtoni males into three groups, thus further capturing the complex social dynamic of this model organism.     

Temperature and salinity tolerances of larval Californian grunion, Leuresthes tenuis (Ayres): A comparison with gulf grunion, L. Sardina (Jenkins & Evermann)

Temperature and salinity tolerances were determined for larval California grunion, Leuresthes tenuis (Ayres), and compared with previous data for Gulf of California grunion, L. sardina (Jenkins & Evermann). Larvae of similar age and acclimation history showed little interspecific difference in thermal tolerance, as measured by half-hour LT₅₀ values for 20–30 day old late postlarvae acclimated at various temperatures, and by upper and lower incipient lethal temperatures for 18°C-acclimated prolarvae. The upper incipient lethal temperature differed by 1 deg.-C (32°C for L. tenuis, 31°C for L. sardina), while the lower incipient lethal temperature for the 18°C acclimated prolarvae of both species was 7.5°C. L. tenuis larvae were much less euryhaline than L. sardina, with incipient lethal salinities of 4.2–41 %. for prolarvae and 8.6–38 %. for 20-day-old postlarvae; comparable values for L. sardina are 4–67.5 %. and 5–57.5 %. Both species show a decrease in temperature and salinity tolerance with age. The larvae of these disjunct congeners show a significant physiological divergence in euryhalinity but not in overall temperature tolerance. These tolerances are discussed in relation to the respective geographic ranges and behavioral responses of the two species.     

Physiological and behavioral responses to strangers compared to friends as a source of disgust

Known as the source effect, feelings of disgust have been found to differ depending on the source of the disgusting material, with that emanating from oneself and familiar others eliciting less disgust than that of strangers. We tested the source effect on self-report of disgust feelings (Study 1), physiological response in heart rate (Study 2), and behavioral response in terms of approach–avoidance movement (Study 3). The results showed significantly higher levels of disgust feelings, more reduced heart rates, and faster avoidance behavior when processing disgusting material associated with strangers compared to that of familiar persons. Together these findings support the evolutionary view that disgust, as part of the human behavioral immune system to drive avoidance from disease-carrying agents, will likely be activated more intensely and quickly in response to unfamiliar as compared to familiar conspecifics who carry common germs more defendable by our shared physical immunity.     

Relationship between Sevoflurane Plasma Concentration,Clinical Variables and Bispectral Index Values during Cardiopulmonary Bypass

Background

Anesthetic administration is increasingly guided by electroencephalography (EEG)-based monitoring, such as the bispectral index (BIS). However, during cardiopulmonary bypass (CPB), factors other than the administered hypnotic agents may influence EEG signals, and their effects on BIS values are unknown.

Methods

This report is a secondary analysis of data from a prospective, controlled interventional study comparing the effect of sevoflurane administration guided by BIS monitoring (group Sevo_BIS) and constant administration of sevoflurane (group Sevo_1.8Vol%) during CPB. Sevoflurane plasma concentration (SPC) was measured using gas chromatography. The relationships of BIS to SPC, CPB pump flow, arterial pressure, hematocrit, temperature, time on CPB, and patient characteristics were analysed.

Results

No association was observed between BIS values and SPC in group Sevo_BIS. In group Sevo_1.8Vol%, a 40 μg ml^-1 increase in SPC, which encompassed the entire range of observed values of the SPC in this analysis, was associated with a decrease of 3.6 (95% confidence interval (CI): 1.1–6.1) in BIS values (p = 0.005). Each increase in CPB time of 10 minutes was associated with an increase in BIS values of 0.25 (95%CI: 0.11–0.39, p<0.001). Path analysis revealed that the BIS values of Sevo_BIS patients were 5.3 (95%CI: 3.2–7.5) units higher than those of Sevo_1.8Vol% patients (p<0.001), which was the strongest effect on BIS values. Path analysis revealed a slope of 0.5 (95%CI: 0.3–0.7) BIS units per 1°C body temperature (p<0.001).

Conclusion

BIS monitoring is insensitive to clinically relevant changes in SPC in individual patients during CPB.