Publications by authors named "Michael Varnum"

How do natural changes in disease avoidance motivation shape thoughts about and behaviors toward ingroup and outgroup members? During the COVID-19 pandemic, political party affiliation has been a strong predictor in the United States of COVID-19-related opinions, attitudes, and behaviors. Using a six-wave longitudinal panel survey of representative Americans (on Prolific, = 1,124, from April 2020 to February 2021), we explored how naturally occurring changes across time in both risks of COVID-19 infection and people's disease avoidance motivation shaped thoughts about and behaviors toward Republicans and Democrats (e.g.

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We examine the opportunities and challenges of expert judgment in the social sciences, scrutinizing the way social scientists make predictions. While social scientists show above-chance accuracy in predicting laboratory-based phenomena, they often struggle to predict real-world societal changes. We argue that most causal models used in social sciences are oversimplified, confuse levels of analysis to which a model applies, misalign the nature of the model with the nature of the phenomena, and fail to consider factors beyond the scientist's pet theory.

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Many animal species exhibit seasonal changes in their physiology and behavior. Yet despite ample evidence that humans are also responsive to seasons, the impact of seasonal changes on human psychology is underappreciated relative to other sources of variation (e.g.

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How much cultural variation is explained by the physical and social ecologies people inhabit? Here, we provide an answer using nine ecological variables and 66 cultural variables (including personality traits, values and norms) drawn from the EcoCultural Dataset. We generate a range of estimates by using different statistical metrics (e.g.

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At the onset of the COVID-19 pandemic, psychological scientists frequently made on-the-record predictions in public media about how individuals and society would change. Such predictions were often made outside these scientists' areas of expertise, with justifications based on intuition, heuristics, and analogical reasoning (Study 1; = 719 statements). How accurate are these kinds of judgments regarding societal change? In Study 2, we obtained predictions from scientists (N = 717) and lay Americans ( = 394) in Spring 2020 regarding the direction of change for a range of social and psychological phenomena.

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Adult zebrafish respond to retinal injury with a regenerative response that replaces damaged neurons with Müller glia-derived regenerated neurons. The regenerated neurons are functional, appear to make appropriate synaptic connections, and support visually mediated reflexes and more complex behaviors. Curiously, the electrophysiology of damaged, regenerating, and regenerated zebrafish retina has only recently been examined.

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Introduction: Zebrafish regenerate their retinas following damage, resulting in restoration of visual function. Here we evaluate recovery of retinal function through qualitative and quantitative analysis of the electroretinogram (ERG) over time following retinal damage, in correlation to histological features of regenerated retinal tissue.

Methods: Retinas of adult zebrafish were lesioned by intravitreal injection of 10 μM (extensive lesion; destroys all neurons) or 2 μM (selective lesion; spares photoreceptors) ouabain.

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Why has fiction been so successful over time? We make the case that fiction may have properties that enhance both individual and group-level fitness by (a) allowing risk-free simulation of important scenarios, (b) effectively transmitting solutions to common problems, and (c) enhancing group cohesion through shared consumption of fictive worlds.

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Scholars interested in cultural diversity have long suggested that similarities and differences across human populations might be understood, at least in part, as stemming from differences in the social and physical ecologies individuals inhabit. Here, we describe the EcoCultural Dataset (ECD), the most comprehensive compilation to date of country-level ecological and cultural variables around the globe. ECD covers 220 countries, 9 ecological variables operationalized by 11 statistical metrics (including measures of variability and predictability), and 72 cultural variables (including values, personality traits, fundamental social motives, subjective well-being, tightness-looseness, indices of corruption, social capital, and gender inequality).

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The COVID-19 pandemic caused drastic social changes for many people, including separation from friends and coworkers, enforced close contact with family, and reductions in mobility. Here we assess the extent to which people's evolutionarily-relevant basic motivations and goals-fundamental social motives such as Affiliation and Kin Care-might have been affected. To address this question, we gathered data on fundamental social motives in 42 countries ( = 15,915) across two waves, including 19 countries (  10,907) for which data were gathered both before and during the pandemic (pre-pandemic wave: 32 countries,  = 8998; 3302 male, 5585 female;   24.

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How does psychology vary across human societies? The fundamental social motives framework adopts an evolutionary approach to capture the broad range of human social goals within a taxonomy of ancestrally recurring threats and opportunities. These motives-self-protection, disease avoidance, affiliation, status, mate acquisition, mate retention, and kin care-are high in fitness relevance and everyday salience, yet understudied cross-culturally. Here, we gathered data on these motives in 42 countries (N = 15,915) in two cross-sectional waves, including 19 countries (N = 10,907) for which data were gathered in both waves.

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Fertility rates have been declining worldwide over the past 50 years, part of a phenomenon known as "the demographic transition." Prior work suggests that this decline is related to population density. In the present study, we draw on life history theory to examine the relationship between population density and fertility across 174 countries over 69 years (1950 to 2019).

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Human societies are not static. Attitudes, norms, institutions, behavior, and cultural products shift over time, sometimes with dizzying speed. However psychological science has either largely ignored cultural change or tacitly treated it as a source of noise.

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How do experts in human behavior think the world might change after the coronavirus (COVID-19) pandemic? What advice do they have for the postpandemic world? Is there a consensus on the most significant psychological and societal changes ahead? To answer these questions, we analyzed interviews from the World After COVID Project-reflections of more than 50 of the world's top behavioral and social science experts, including fellows of National Academies and presidents of major scientific societies. These experts independently shared their thoughts on possible psychological changes in society in the aftermath of the COVID-19 pandemic and provided recommendations how to respond to the new challenges and opportunities these shifts may bring. We distilled these predictions and suggestions via human-coded analyses and natural language processing techniques.

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Although casual sex is increasingly socially acceptable, negative stereotypes toward women who pursue casual sex remain pervasive. For example, a common trope in television, film, and other media is that women who engage in casual sex have low self-esteem. Despite robust work on prejudice against women who engage in casual sex, little empirical work has focused on the lay theories individuals hold about them.

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Cultural neuroscience research has provided substantial evidence that culture shapes the brain by providing systematically different sets of experiences. However, cultures are ever-changing in response to the physical and social environment. In the present paper, we integrate theories and methods from cultural neuroscience with the emerging body of research on cultural change and suggest several ways in which the two fields can inform each other.

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We propose that grounded procedures may help explain psychological variations across cultures. Here we offer a set of novel predictions based on the interplay between the social and physical ecology, chronic sensorimotor experience, and cultural norms.

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Song lyrics are rich in meaning. In recent years, the lyrical content of popular songs has been used as an index of culture's shifting norms, affect, and values. One particular, newly uncovered, trend is that lyrics of popular songs have become increasingly simple over time.

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Empathy has been a key focus of social, developmental, and affective neuroscience for some time. However, research using neural measures to study empathy in response to social victimization is sparse, particularly for young children. In the present study, 58 children's (White, non-Hispanic; five to nine years old) mu suppression was measured using electroencephalogram methods (EEG) as they viewed video scenarios depicting social injustices toward White and Black children.

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Objective: We test the proposition that both social orientation and cognitive style are constructs consisting of loosely related attributes. Thus, measures of each construct should weakly correlate among themselves, forming intraindividually stable profiles across measures over time.

Method: Study 1 tested diverse samples of Americans (N = 233) and Japanese (N = 433) with a wide range of measures of social orientation and cognitive style to explore correlations among these measures in a cross-cultural context, using demographically heterogeneous samples.

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Article Synopsis
  • The study investigated how culture influences the regulation of neural responses related to emotions, specifically using a measure called the late positive potential (LPP).
  • European Americans and Mexican participants successfully regulated their LPP responses to both positive and negative images, while Mexican participants specifically managed to down-regulate their responses to positive images.
  • In contrast, participants from Chinese cultural backgrounds showed no significant ability to up- or down-regulate their LPP responses, highlighting cultural differences in emotional regulation.
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What motives do people prioritize in their social lives? Historically, social psychologists, especially those adopting an evolutionary perspective, have devoted a great deal of research attention to sexual attraction and romantic-partner choice (mate seeking). Research on long-term familial bonds (mate retention and kin care) has been less thoroughly connected to relevant comparative and evolutionary work on other species, and in the case of kin care, these bonds have been less well researched. Examining varied sources of data from 27 societies around the world, we found that people generally view familial motives as primary in importance and mate-seeking motives as relatively low in importance.

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Baumard proposes a model to explain the dramatic rise in innovation that occurred during the Industrial Revolution, whereby rising living standards led to slower life history strategies, which, in turn, fostered innovation. We test his model explicitly using time series data, finding limited support for these proposed linkages. Instead, we find evidence that rising living standards appear to have a time-lagged bidirectional relationship with increasing innovation.

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