Monday, April 17, 2023

Income raises human well-being indefinitely, but the impacts gradually become marginal with higher income; age consistently slashes well-being

Income raises human well-being indefinitely, but age consistently slashes it. Chao Li & Shunsuke Managi. Scientific Reports volume 13, Article number: 5905. Apr 11 2023. https://www.nature.com/articles/s41598-023-33235-7

Abstract: The relationships among human well-being, income, and age have long been debated. The association between human well-being and income is believed to be U-shaped, although the reasons remain elusive. A recent study shows a turning point in the link between human well-being and income; that is, increased income does not always improve well-being. However, the mechanisms of the effects of income and age on human well-being are unknown. Here, we illustrate the total cumulative effects of income and age on evaluated well-being through all observed causal pathways based on a 1.6-million-observation global dataset and the structural causal model. This is the first study to investigate those casual relationships globally. We find that an increase in age always reduces evaluated well-being, and the adverse effects are aggravated with age. Furthermore, increased income continuously improves human well-being, but the impacts gradually become marginal with higher income. Our results demonstrate that physical health improvement in older people is the most effective way to intervene against the harmful effects of age on well-being. Moreover, increased income may dramatically enhance the well-being of people living close to the poverty line.

Conclusion

This is the first study to investigate the causal relationships among human well-being, income, and age using a global dataset. Intervention for gradually deteriorating health in an aging society is the most effective way to maintain or improve human well-being. While increasing age is not inherently detrimental to human well-being, it can lead to various physical and mental health issues that ultimately harm overall well-being. Additionally, the effectiveness of an increase in income is typically most pronounced when individuals initially have low incomes. Although a turning point in the relationship between well-being and income, such as 60,000 to 75,000 USD/year, regarding life evaluation was not detected, the contribution of increased income to life evaluation beyond these amounts is marginal. Increased income always leads to human well-being improvement because its effects on the direct and indirect factors are always positive in most pathways observed in this study.

Participants had better memory for tweets than news headlines

Memory for tweets versus headlines: Does message consistency matter? Tori Peña, Raeya Maswood, Melissa Chen, Suparna Rajaram. Applied Cognitive Psychology, April 13 2023. https://doi.org/10.1002/acp.4068

Abstract: People routinely use news outlets and social media platforms to keep up with recent events. While information from these common sources often aligns in the messages conveyed, news headlines and microblogs on social media also frequently provide contradictory messages. In this study, we examined how people recall and recognize tweets and news headlines when these sources provide inconsistent messaging. We tested this question in person (Experiment 1) and online (Experiment 2). Participants studied news headlines and tweets that provided either consistent messaging or inconsistent messaging, then completed a free recall and recognition memory task sequentially, and provided confidence ratings for recognition judgments. Findings were similar across memory tasks and experiments: Participants had better memory for tweets than news headlines regardless of message consistency. We discuss the implications of these findings for understanding memory in the digital age where social media use is widespread and messaging across sources is often inconsistent.


Sunday, April 16, 2023

Harbingers of failure do exist: Their positive (negative) pre-release movie reviews provide a strong predictive signal that the movie will turn out to be a flop (success)

What reviews foretell about opening weekend box office revenue: the harbinger of failure effect in the movie industry. Pantelis Loupos, Yvette Peng, Sute Li & Hao Hao. Marketing Letters, April 13 2023. https://link.springer.com/article/10.1007/s11002-023-09665-8


Abstract: We empirically investigate the harbinger of failure phenomenon in the motion picture industry by analyzing the pre-release reviews written on movies by film critics. We find that harbingers of failure do exist. Their positive (negative) pre-release movie reviews provide a strong predictive signal that the movie will turn out to be a flop (success). This signal persists even for the top critic category, which usually consists of professional critics, indicating that having expertise in a professional domain does not necessarily lead to correct predictions. Our findings challenge the current belief that positive reviews always help enhance box office revenue and shed new light on the influencer-predictor hypothesis. We further analyze the writing style of harbingers and provide new insights into their personality traits and cognitive biases.


Conclusions and discussion

Predicting a movie’s box office revenue is one of the most fundamental needs in the motion picture industry. This becomes even more challenging when someone tries to predict the opening weekend box office revenue since there is little to no information available about the wider audience’s reaction. As Cabral and Natividad (2016) show in their work, doing well at the box office during the opening weekend has an economically and statistically significant effect on the movie’s eventual performance. Prior research has explored how different attributes of a movie, such as star inclusion (Elberse, 2007; Karniouchina, 2011; Liu et al., 2014), the activity level of editors and viewers of the movie’s corresponding entry in Wikipedia (Mestyán et al., 2013), and competition among movies that are released at the same time (Ainslie et al., 2005; Hennig-Thurau et al., 2007; Delre et al., 2016), could predict the box office performance. With regard to online movie reviews, Moon et al. (2010) show that movie ratings from professional critics and viewers’ communities are predictive of total box office revenue. Moreover, Basuroy et al. (2003) find that both positive and negative reviews are significantly correlated with box office revenue with the impact of negative reviews (but not positive reviews) diminishing over time. We diverge from this research and propose that a distinction should be made among movie critics because as we demonstrate not all positive (negative) reviews are a signal for success (failure).

More specifically, we combine three different data sources to empirically investigate the harbinger of failure phenomenon in the motion picture industry. We analyze the pre-release reviews written on movies by film critics and find that harbingers of failure do exist. Their positive pre-release reviews provide a strong predictive signal that the movie will turn out to be a flop. Moreover, we find the harbinger effect to be symmetric. That is, there are harbinger critics who give negative reviews and the movie turns out to be successful. These findings shed new light on the influencer-predictor hypothesis. We document that in a pre-release setting, there is a portion of movie critics that neither influence nor predict the right outcome of a movie. On the contrary, the outcome of the movie turns out to be the exact opposite of their prediction.

We further analyze the writing style of film critics and connect them to potential cognitive biases that might give rise to the harbinger phenomenon. We find that harbinger critics engage in an analytical and formal style of writing and have a lower rate of self-reference pronouns compared to non-harbingers. These differences indicate that harbinger critics are less self-reflective about the audience’s opinion compared to non-harbingers and tend to show overconfidence in their abilities. When we stratify the analysis across the critic status category, we find the aforementioned differences between harbingers and non-harbingers to be even more significant. In the cohort of top critics, which usually consists of professional and experienced reviewers, we find that top critic harbingers are also using more adverbs than their counterparts in their positive reviews indicating that they are over-optimistic in their assessments of movies. In the case of negative reviews, we find that the top critic harbingers are significantly more analytical than their counterparts.

Our findings have important managerial implications for the motion picture industry and its key channel entities: movie studios, distribution companies, and movie theaters. First, our research provides a methodology based on pre-release film reviews that allows movie producers and distributors to identify early on which movies are going to perform badly. This will in turn allow them to make better pre-launch marketing decisions and save significant marketing costs on flop movies. It will also allow theaters to better allocate their theater space, a finite resource that is crucial to the success of theaters. Second, film studios can greatly benefit from identifying the harbinger critics and using them during the early stages of production. More specifically, movie studios can use harbinger critics to select the scripts that will maximize their box office revenue instead of using mere guesswork. Our approach complements that of Eliashberg et al. (2007), which uses natural-language processing to select the winning scripts. Third, our approach can potentially serve as a diagnostic for reviewers across fields. It is crucial for companies that employ reviewers to know whether their reviewers’ opinions can be used as a diagnostic tool to determine success or failure. Based on that, companies might want to reclassify who they designate as a “top reviewer” or create a new class of reviewers.

We should acknowledge here the limitations of this work and present potential future research avenues. The main limitation of our research, similar to Anderson et al. (2015) and Simester et al. (2019), is that we do not provide a causal explanation about where the harbingers’ preferences are coming from. However, we do provide insights into their personality traits and cognitive biases based on their writing style. This paves new avenues for further experimental behavioral research about the underlying mechanisms of the harbinger phenomenon. A second potential limitation of our research is that movie producers and distributors could potentially strategically pick which critics to invite to their pre-release screenings. However, there is no substantial evidence that this is happening in the movie industry, as it would jeopardize the reputation of, and confidence in, movie studios and movie critics alike. Last, another possibility, unobserved to the researcher, is that critics are getting influenced by other critics before they submit their review by either reading their reviews or talking to them. Future research might include further contextual variables, such as the choice of movies to review by harbingers, the timing of the reviews, and the lack of learning, to further the theoretical understanding of the harbinger phenomenon in the motion picture industry.

To conclude, does the positive (negative) feedback given by film critics before the release of a movie signal its financial failure (success) instead of its success (failure) as currently believed? Our findings document that this is not always the case. At least in a pre-release movie setting, a distinction should be made among film critics because of the existence of harbinger critics; their endorsement of a movie is a signal of the opposite outcome. 

The origin of pleasant sensations: insight from direct electrical brain stimulation

The origin of pleasant sensations: insight from direct electrical brain stimulation. Cécile Villard et al. Cortex, April 13 2023. https://doi.org/10.1016/j.cortex.2023.03.007

Abstract: Research into the neuroanatomical basis of emotions has resulted in a plethora of studies over the last twenty years. However, studies about positive emotions and pleasant sensations remain rare and their anatomical-functional bases are less understood than that of negative emotions. Pleasant sensations can be evoked by electrical brain stimulations (EBS) during stereotactic electroencephalography (SEEG) performed for pre-surgical exploration in patients with drug-resistant epilepsy. We conducted a retrospective analysis of 10 106 EBS performed in 329 patients implanted with SEEG in our epileptology department. We found that 13 EBS in 9 different patients evoked pleasant sensations (0.60% of all responses). By contrast we collected 111 emotional responses of negative valence (i.e., 5.13 % of all responses). EBS evoking pleasant sensations were applied at 50 Hz with an average intensity of 1.4 ± 0.55 mA (range 0.5−2 mA). Pleasant sensations were reported by nine patients of which three patients presented responses to several EBS. We found a male predominance among the patients reporting pleasant sensations and a prominent role of the right cerebral hemisphere. Results show the preponderant role of the dorsal anterior insula and amygdala in the occurrence of pleasant sensations.

Keywords:Brain stimulationPositive emotionstereoelectroencephalographyAmygdalaInsula

4. Discussion

To our knowledge, our study is the first to focus specifically on the generation of pleasant sensations, in the broad meaning of the term, from a large collection of EBS obtained during SEEG recordings (10 106 stimulations in 329 patients). We found that pleasant sensations were exceptional events during EBS, much rarer than negative sensations, as we observed only 13 positives sensations (0.55%, versus 5.13 % for negative feelings). This is possibly a particularity of the mammalian brain, which is more likely to generate negative emotions for rapid adaptive reactions favoring survival of species, e.g. when facing a danger(Phan et al., 2002). Another explanation lies in the largely subcortical and brainstem location of reward networks(Liu et al., 2011Wise, 2002) when compared to the focus of EBS on cortical structures during SEEG for presurgical evaluation of epilepsy (see limitations).

4.1. Amygdala and anterior insula: two core regions for pleasant sensations

Our results identified two brain regions more frequently involved in pleasant sensations: the anterior insula (AI) and the amygdala. The AI is the source of heterogeneous clinical manifestations when it is involved in seizure or stimulated electrically as it can evoke gustatory, olfactory, auditory, somatosensitive, vestibular, viscerosensitive, visceromotor, experiential or emotional sensations(Mazzola et al., 2006201420172019). Functional neuroimaging highlighted the role played by the insula in the integration of information from our environment and the genesis of adapted emotions, showing the notable role of the AI(Kurth et al., 2010). Our data are congruent with previous EBS studies showing the involvement of AI in pleasant emotions and particularly ecstatic sensations (Bartolomei et al., 2019Nencha et al., 2022aOstrowsky et al., 2000). Gschwind and Picard (2016), in a meta-analysis of ecstatic aura, defined ecstatic sensations as the association of "intense positive emotion (bliss)", "improved physical well-being", "increased self-awareness or increased perception of the external world (clarity)". According to a recent neurocognitive theory, the brain would operate on a prediction model (Clark, 2013), comparing real internal and external stimuli with reference theoretical patterns. The insula would be the key structure for processing the internal states of the body through interoceptive signals. Disruption of the predictive role of AI has been proposed as an explanation of the ecstatic auras(Picard et al., 2021). Recently a feeling of time dilation with a sense of pleasant eternity has been reported during AI stimulation (Sheikh et al., 2022).

The role of amygdala in generating negative emotions, especially fear, is well known both from animal and human studies(Davis & Whalen, 2001LeDoux, 2003). However, the amygdala has also been involved in brain circuits related to happiness and pleasant sensations(Garavan et al., 2001Hamann & Mao, 2002Lanteaume et al., 2007Sabatinelli et al., 2011). Animal studies showed that amygdala neurons respond to conditioning stimuli that have been associated with either appetitive or aversive outcomes (reviewed in Fernando et al., 2013). The activation of the amygdala in response to pleasant stimuli is suggested by human fMRI studies, notably when observing a pleasant image, face, word or scene(Garavan et al., 2001Hamann & Mao, 2002Sabatinelli et al., 2011), or during mental imagery of pleasant situations(Costa et al., 2010). On the other hand, only few publications reported pleasant sensations during EBS in the amygdala (see (Guillory & Bujarski, 2014) for review). Lanteaume et al. (2007) reported sensations of "joy" or "happiness" during left amygdala stimulation in a minority of patients, as most EBS resulted in negative sensations. This study quantified subjective responses using a basic emotion scale (Izard scale). A more recent study found that only one out of 150 amygdala stimulation resulted in a subjective feeling of joy (Inman et al., 2020).

Our study also shows that the anterior cingulate gyrus and the temporal pole may also contribute to pleasant sensations. These observations are consistent with some data from EBS of the temporal pole. Analyzing the semiological aspects of temporal pole stimulation, Ostrowsky et al. (2000) reported a sensation of happiness in 4 out of 150 temporal pole stimulation. Meletti et al. (2006) also described a pleasant and relaxing sensation during EBS in the temporal pole. Similarly, experiments involving recollection of positive autobiographical memories and positive emotions revealed the activation of hippocampus and temporo-polar regions(Markowitsch et al., 2003Zotev et al., 2011)Concerning the anterior cingulate gyrus, in his work on the lateralization of affect, Smith et al. (2006a) described an euphoric sensation after its stimulation. Some functional imaging studies highlighted also the role of the anterior cingulate gyrus in the emotional mechanisms of happiness. Studies reported that when participants were asked to recall and attempt to re-experience and re-enact intense personal emotional episodes, there was an activation of the right insula, right somatosensory cortex, bilateral anterior cingulate cortex and right posterior cingulate cortex (Damasio et al., 2000; Suardi et al., 2016).

While our study highlights the predominant role in the conscious expression of positive affect of the AI and amygdala, these structures are likely embedded in a network of neural structures and probably do not act in isolation. There is evidence that direct high-frequency EBS activates a network of regions depending on the stimulation site and the effect produced(Bartolomei et al., 2019Perrone-Bertolotti et al., 2020). As such, a recent study on a manic state induced by EBS of the right lateral prefrontal cortex demonstrated significant increase of functional coupling between the right hemispheric limbic nodes, the temporal pole and the claustrum(Scholly et al., 2022). There is evidence that the genesis of emotions requires the interaction between several brain networks, widely distributed, although none of them seems to be specific to the "emotion function” (Morawetz et al., 2020Pessoa, 2018). Among these networks, the "salience network", which has been widely studied, would be involved in a larger scale network leading to the generation of emotions. The salience network involves, among others, connections between the anterior cingulate gyrus, the AI, the amygdala and the hypothalamus (Kober et al., 2008; Lindquist et al., 2016; Pessoa, 2018). The relative contribution of each of these regions in positive emotion networks remains to be determined.

A network of brain areas underpinning the experience of positive emotions and pleasant sensations could explain why, in two patients, stimulating different structures evoked the same sensations, with for patient P4, stimulation of the right amygdala and temporal pole evoking a feeling of well-being and for patient P8, stimulation of the right amygdala and AI evoking a feeling of well-being and positive emotion. The dense bidirectional connections between the anterior ventral part of the insula and the amygdala(Jakab et al., 2012Mesulam & Mufson, 1982) and between the AI and the anterior cingulate gyrus (Ghaziri et al., 2017) can account for similar sensations evoked by EBS in distant areas within the same functional network.

4.2. Effect of hemispheric laterality and sex

Our study revealed a right-sided predominance of pleasant sensations. A right-side predominance of negative emotional valence induction for right side stimulations has been reported in previous EBS studies (review in (Guillory & Bujarski, 2014)). A left lateralization of positive emotion during amygdala stimulation has been previously suggested (Lanteaume et al., 2007). This apparent contradiction could be linked to the underrepresentation in the previous studies of the anterior insula stimulation which is the prominent site in our experience for pleasant evoked sensations. Smith et al. (2006b) also reported dysphoric responses primarily during right stimulation, but no lateralization for pleasant emotional responses. No clear lateralization effect was found as a function of emotional valence in amygdala activation in a large neuroimaging meta-analysis(Baas et al., 2004).

There was a predominance of pleasant sensations in men in our study. No previous study using EBS has reported such a predominance of positive emotions, which could be related to the small number of patients in most EBS studies when compared to the large sample investigated here. However, regarding negative emotions Meletti et al. (2006) reported that the feeling of fear occurred significantly more in women than in men.

Data in the literature on gender differences in emotion are often inconsistent (Brody & Hall, 2000Wester et al., 2002). There is evidence, primarily from self-report data, that women experience emotions with greater intensity than men(Whittle et al., 2011). Women have been found to be more reactive to emotional stimuli, and particularly to unpleasant, threatening, or traumatic stimuli. Research has also suggested that gender differences in self-report are greater for negative emotions such as fear and jealousy, and some neuroimaging studies support greater brain activation in women for negative stimuli (review in (Whittle et al., 2011)). There is also evidence that males may be physiologically more reactive to certain pleasurable stimuli, particularly erotic ones (Allen et al., 2007). A study reported that males exhibited greater activity than females in the frontal lobe and amygdala during exposure to photo stimuli with positive valence (Wrase et al., 2003).

Further studies are needed to better define the effects of these two factors in the genesis of pleasant sensations.

4.3. Limitations of the study

The first limitation of our study is its retrospective nature. Responses were systematically collected, but subjective reports may not have been exhaustive. Patients may have described their symptoms in a simplified way because of difficulties in expressing their feelings (Cirignotta et al., 1980). Moreover, how to perceive and express these sensations may depend on education, culture, information given to the patients, context of occurrence, the patients ability to introspection, their vocabulary and therefore vary between patients but also within the same patient (Williams, 1956). To overcome these difficulties, quantification by self-administered questionnaires (Lanteaume et al., 2007) is interesting but was not carried out in the majority of patients in the study. Prospective studies using standardized questionnaires will be particularly useful, especially if coupled with objective measures of the autonomic response, such as the electrodermal response(Inman et al., 2020Lanteaume et al., 2007).

The second limitation is related to the spatial sampling of SEEG as it has been estimated that about 10,000 electrode contacts would be necessary to explore the brain volume covered by functional MRI(Lachaux et al., 2003). This limitation is partially counterbalanced by the large cohort of patients included and the large number of EBS considered in our analysis (the highest in the literature to date) that allow a large spatial sampling. In addition, the included patients cover a large temporal period with variations in the number of implanted electrodes and implanted sites. Insular implantations with orthogonal and especially oblique electrodes became more common from 2010 in our center. We can also note that, for feasibility and safety reasons, some regions cannot be explored, in particular the brainstem whose role in emotional processing is important (Venkatraman et al., 2017).

Third, SEEG was performed in patients with epilepsy, and seven of them reported positive sensations belonging to the subjective symptoms of their usual seizures. Moreover, the stimulated sites were part of the epileptogenic zone in 8 out of 13 cases. Indeed, the organization of brain networks and the excitability of the brain of patients with epilepsy may be different from a non-epileptic subject. Nevertheless, direct brain stimulation in the history of neuroscience has allowed progress in the knowledge of the role of certain regions in subjective phenomena generated by the human brain, such as psychosensory or emotional phenomena (reviewed (Trébuchon & Chauvel, 2016). Moreover, these phenomena can be obtained outside the usual clinical semiology of the patients (patients P1 and P7 in the present study) (Nencha et al., 2022b).

Saturday, April 15, 2023

The presumption of innocence, the prohibition against pretrial punishment, and the right to an impartial jury—constitutional bedrocks of the American criminal justice process—are potentially threatened by the practice of “perp walks”

Punishment before trial: public opinion, perp walks, and compensatory justice in the United States.Shanna R. Van Slyke, Leslie A. Corbo & Michael L. Benson. Crime, Law and Social Change volume 79, pages437–452. Nov 17 2022. https://link.springer.com/article/10.1007/s10611-022-10062-x

Abstract: The presumption of innocence, the prohibition against pretrial punishment, and the right to an impartial jury—constitutional bedrocks of the American criminal justice process—are potentially threatened by the practice of “perp walks.” Justice officials, politicians, and the news media have cited public demand as one justification for this controversial practice. Yet, this justification lacks an empirical basis. Drawing from work on procedural fairness, the present study suggests compensatory justice as a framework for understanding why some American citizens might support perp walks. We extend research on public attitudes towards perp walks with data from an internet survey of 1000 U.S. adults. We find that perp walks are not supported by a majority of the public and that attitudes towards perp walks are influenced by perceptions of the pros and cons of perp walks as well as of the legitimacy of the justice system.


Body odour disgust sensitivity is associated with xenophobia: evidence from nine countries across five continents

Body odour disgust sensitivity is associated with xenophobia: evidence from nine countries across five continents.Marta Z. Zakrzewska et al. Royal Society Open Science, April 12 2023. https://doi.org/10.1098/rsos.221407

Abstract: Body odour disgust sensitivity (BODS) reflects a behavioural disposition to avoid pathogens, and it may also involve social attitudes. Among participants in the USA, high levels of BODS were associated with stronger xenophobia towards a fictitious refugee group. To test the generalizability of this finding, we analysed data from nine countries across five continents (N = 6836). Using structural equation modelling, we found support for our pre-registered hypotheses: higher BODS levels were associated with more xenophobic attitudes; this relationship was partially explained by perceived dissimilarities of the refugees' norms regarding hygiene and food preparation, and general attitudes toward immigration. Our results support a theoretical notion of how pathogen avoidance is associated with social attitudes: ‘traditional norms’ often involve behaviours that limit inter-group contact, social mobility and situations that might lead to pathogen exposure. Our results also indicate that the positive relationship between BODS and xenophobia is robust across cultures.

4. Discussion

Understanding the link between disease detection/avoidance and xenophobia is critical for understanding the psychology of inter-group processes. Here, we focus on BODS, a potent sensory disease avoidance function, and how it is associated with xenophobic attitudes. Specifically, the present research used a large sample and a pre-registered set of hypotheses to extend previous findings of a positive relationship between BODS and explicit xenophobia [16] across countries and continents. Of particular interest was to understand whether or not body odour disgust is linked to negative attitudes to refugees because of the perceived dissimilarity of the refugees. We found that this was the case, and that our findings generalized well across most countries.

Most importantly, we show that how strongly people report to be disgusted by body odours is related to negative attitudes towards a fictitious refugee group (i.e. effect of BODS on xenophobia) and our overall effect size was very similar to previous findings in participants from the USA [16]. In the current study, data were analysed from nine culturally different and large samples in Africa, North America, South America, Europe, Asia and Oceania. The observed result was partially explained by how respondents perceived the refugee group as different in terms of food, hygiene and sanitary practices, and general attitudes towards immigration. This is in line with the disease avoidance theory that aims to explain suggesting that social behaviours and attitudes are connected to avoiding pathogens. Importantly, our results indicate that the relationship between BODS and xenophobia generalizes across populations, and can be partially explained by perceived outgroup norms. Our results thus provide support for the traditional norms account [2,4,19]. Hence, rather than geographical or genetic difference, perceived similarity in food preparation practices seems to be a driver of xenophobic attitudes, and it partially mediates the relationship between other key elements of disease avoidance (i.e. BODS) and xenophobia.

We extended previous findings by comparing attitudes towards the unfamiliar fictitious group from EA to attitudes towards a potentially more similar (at least for western cultures) fictitious outgroup coming from EE. Indeed, the EA Drashneans were consistently rated by most respondents as more dissimilar compared with the EE Drashneans; with the exception of Kenya, which is located in Eastern Africa. This manipulation potentially allows for better causal inferences, even if it worked on the intermediate variable only (perceived dissimilarity) and not the outcome (xenophobia); the difference in perception did not translate to higher levels of xenophobia for the EA Drashneans. This result is at odds with our hypothesis as we expected that the unfamiliar group would be both perceived as more different and elicit more negative attitudes (hypothesis 8 in Secondary hypotheses). However, even though EA Drashneans were perceived as more dissimilar, both groups were generally rated as being quite dissimilar, which might explain the lack of differences in the attitudes towards the two groups. Hence, while perceived group similarity is important in understanding the link between BODS and social attitudes, understanding the underlying mechanisms by which dissimilarity operates in these processes needs further exploration.

One limitation of the current study is that it is cross-sectional, comparing attitudes of individuals at one point in time. Exploring changing attitudes in a longitudinal perspective would add important knowledge on how the disgust/xenophobia relation evolves. As with most behavioural research, our study is also vulnerable to sample bias. For example, our study might have over-sampled from the more educated portions within the populations of reference. This might have an impact on the overall levels of xenophobia, since education typically is associated with lower levels of prejudice [35]. Similarily, our sample might be selective in terms of personality factors (e.g. openness to experience), which are also known to relate to prejudice (e.g. [36,37]). However, given the strengths of our study (e.g. the size and demographic stratification of the sample) in combination with the fact that results generalized well across nine countries, we are confident in the generalizability of our findings in a global context.

Our study points to several new lines of investigations relevant for future research in the field. Although explored only superficially in this study, there seems to be certain variability in the strength of the relationship between BODS and social attitudes. The effect was largest in Canada, and several other Western, English-speaking countries, but it was absent in Kenya—one East African country in our study. Such variability is not unexpected, as recent multi-country studies show variation even in highly robust findings [38]. It would be interesting to see if this variability is related to specific geographical, cultural or pandemic-related factors. Given the heterogeneity of our surveyed countries, however, such enquiries are outside the scope of the present study. An interesting topic to explore more with regard to pathogens and social interactions would be to see how disease avoidance affects other, less explored senses such as taste and touch. In fact, a recent study suggests that disease history might be related to affective touch diversity towards a close one [39]. Another important area of future research pertains to how individual differences related to disease avoidance mechanisms translate into behaviours during heightened risk of contamination, such as the COVID-19 pandemics. For example, it is unclear whether the COVID-19 pandemic has increased general levels of xenophobia [40]. However, what the current study shows is that the relationship between levels of BODS and xenophobia is similar to relations observed in an earlier, pre-pandemic study. This could suggest that a salient pathogen threat does not necessarily dramatically affect relations between disgust and attitudes towards fictitious outgroups of varying similarity.

The positive correlation between contradictory conspiracy beliefs mostly reflects that disbelieving one conspiracy theory predicts an increased likelihood of disbelieving a contradictory one

Just Dead, Not Alive: Reconsidering Belief in Contradictory Conspiracy Theories. Jan-Willem van Prooijen et al. Psychological Science, April 11, 2023. https://doi.org/10.1177/09567976231158570

Abstract: A well-established finding is that beliefs in contradictory conspiracy theories (e.g., Princess Diana was murdered vs. faked her own death) are positively correlated. This is commonly interpreted as evidence that people systematically believe blatant inconsistencies. Here, we propose that the field has insufficiently acknowledged a compelling alternative explanation: Disbelieving both conspiracy theories also yields a positive correlation. In four preregistered studies (total N = 7,641 adults), online participants evaluated 28 sets of contradictory conspiracy theories. Although the positive correlation was replicated in all cases, this was mostly due to participants who believed the official versions of these events (e.g., Princess Diana died in a car accident). Among participants who disbelieved these official stories, the correlation was inconsistent at best. A mini meta-analysis revealed a negative correlation among these participants, which was particularly due to the dead-or-alive cases. Apparently, researchers should reconsider the notion of systematic belief in contradictory conspiracy theories.

General Discussion

The results of four preregistered studies in three countries, along with a meta-analysis, yielded the following conclusions. First, beliefs in contradictory conspiracy theories are positively correlated, replicating the basic finding of Wood and colleagues (2012). Second, this correlation is mostly attributable to the participants in the sample who believe the official version of events (Studies 1–4) and to a lesser extent those who feel unsure what happened (Study 2). Among participants who disbelieve the official version of events, the positive correlation emerges sporadically but inconsistently. In a meta-analysis, the correlation among these participants was negative, particularly for dead-or-alive cases. Altogether, the positive correlation between contradictory conspiracy beliefs mostly reflects that disbelieving one conspiracy theory predicts an increased likelihood of disbelieving a contradictory one.
Some of the correlations among participants who disbelieved the official version of these events were underpowered (e.g., the Osama bin Laden case; Studies 3 and 4); moreover, some of the conspiracy theories yielded very low levels of belief (e.g., the theory that Princess Diana faked her own death; Studies 1 and 4). Note that both of these issues speak against (and not in favor of) systematic belief in contradictory conspiracy theories. An underpowered correlation implies that only a small proportion of the sample disbelieved the official version of a particular case to begin with (Imhoff et al., 2022Sutton & Douglas, 2022). Likewise, extremely low levels of belief on one of the items implies that few participants actually believe both contradictory conspiracy theories. And yet a positive overall correlation between contradictory conspiracy theories consistently emerged.
The current findings are limited to the populations and specific conspiracy theories investigated here, and future research may expand to different cultures and contradictory conspiracy theories. Moreover, our findings do not imply that people who believe contradictory conspiracy theories do not exist (see also Lukic et al., 2019Miller, 2020Petrović & Žeželj, 2022). Our data also contained participants who believed contradictory conspiracy theories, as well as other inconsistencies (i.e., believed the official version plus a conspiracy theory), although in low proportions (see Tables S1–S4 in the Supplemental Material). Instead, our findings suggest that researchers have overestimated the predictability and prevalence of such inconsistencies in a conspiratorial mindset.
This insight raises important new questions. For instance, to what extent is the correlation between conspiracy beliefs that are not mutually incompatible (often seen as reflecting a conspiratorial mindset) actually due to people who disbelieve both conspiracy theories? It is quite plausible that, among conspiracy theorists, the strength of this association is weaker than commonly assumed. More generally, the current studies underscore the methodological point that taking correlations at face value—without carefully examining underlying response distributions—can yield misguided conclusions.
This research domain hence should reconsider the notion of systematic belief in contradictory conspiracy theories. Certainly, many conspiracy theories are epistemically irrational in that they are based on weak evidence, pseudoscience, motivated reasoning, and unreliable sources. Moreover, most conspiracy theories do more harm than good for society (e.g., Douglas et al., 2019Jolley & Douglas, 2014Jolley et al., 2019van der Linden, 2015van Prooijen et al., 2022). That does not mean, however, that believing a person was murdered increases the likelihood of believing that same person faked their own death. It is time for the research field of conspiracy theories to accept the obvious: When people believe a person is dead, they are not more likely to believe that same person is still alive.