Do sleep disruptions promote social fragmentation?

Sleep changes predate shifts in mood/affect, thought processing, mental and physical health, civic engagement, and contextual circumstances, among other things. Theory predicts that these changes may lead to shifts in political and social beliefs. Do sleep disruptions shape how individuals see the world, the people around them, and themselves in relation to others? In this article, we use daily survey data from the 77 waves (N ≈ 460,000) of the University of California, Los Angeles's 2019-2021 Nationscape Survey-a nationally representative political survey-to examine the effect of an exogenous short-term sleep disruption on measures of political views, polarization, and discriminatory beliefs. Using this data set, we leverage the modest sleep disruption that occurs at the start (and end) of Daylight Saving Time (DST) and employ a regression discontinuity in time design around the precise DST cutoff (which we supplement with event study models). Despite strong theoretical expectations and correlational connection between measures of sleep and many outcomes related to social fragmentation, we find that the DST change has little to no causal effect on citizens' levels of polarization or their discriminatory attitudes. These effects are precise enough to rule out small effects, robust to a host of specification checks, and consistent across potential subgroups of interest. Our work adds to a small but growing body of research on the social and political effects of sleep disruptions.

Social and moral psychology of COVID-19 across 69 countries.

The COVID-19 pandemic has affected all domains of human life, including the economic and social fabric of societies. One of the central strategies for managing public health throughout the pandemic has been through persuasive messaging and collective behaviour change. To help scholars better understand the social and moral psychology behind public health behaviour, we present a dataset comprising of 51,404 individuals from 69 countries. This dataset was collected for the International Collaboration on Social & Moral Psychology of COVID-19 project (ICSMP COVID-19). This social science survey invited participants around the world to complete a series of moral and psychological measures and public health attitudes about COVID-19 during an early phase of the COVID-19 pandemic (between April and June 2020). The survey included seven broad categories of questions: COVID-19 beliefs and compliance behaviours; identity and social attitudes; ideology; health and well-being; moral beliefs and motivation; personality traits; and demographic variables. We report both raw and cleaned data, along with all survey materials, data visualisations, and psychometric evaluations of key variables.

Education and Public Support for COVID-19 Mitigation Measures.

Governments around the world have adopted many mitigation strategies to stop the spread of the coronavirus disease 2019 (COVID-19) pandemic. Public support for these strategies varies widely. In this visualization the authors examine whether college education might play a role in support for various COVID-19 mitigation strategies. To do so, they leverage original data from surveys conducted across six countries. The authors find that the association between education and support for COVID-19 restrictions varies considerably in direction, both by restriction type and by country. Given this finding, in many contexts, the educational status of the intended audience should be considered in how public health messaging campaigns are developed and targeted.

Validated names for experimental studies on race and ethnicity.

A large and fast-growing number of studies across the social sciences use experiments to better understand the role of race in human interactions, particularly in the American context. Researchers often use names to signal the race of individuals portrayed in these experiments. However, those names might also signal other attributes, such as socioeconomic status (e.g., education and income) and citizenship. If they do, researchers would benefit greatly from pre-tested names with data on perceptions of these attributes; such data would permit researchers to draw correct inferences about the causal effect of race in their experiments. In this paper, we provide the largest dataset of validated name perceptions to date based on three different surveys conducted in the United States. In total, our data include over 44,170 name evaluations from 4,026 respondents for 600 names. In addition to respondent perceptions of race, income, education, and citizenship from names, our data also include respondent characteristics. Our data will be broadly helpful for researchers conducting experiments on the manifold ways in which race shapes American life.

Perceived Motives of Public Diplomacy Influence Foreign Public Opinion.

Although many countries engage in public diplomacy, we know relatively little about the conditions under which their efforts create foreign support for their desired policy outcomes. Drawing on the psychological theory of "insincerity aversion," we argue that the positive effects of public diplomacy on foreign public opinion are attenuated and potentially even eliminated when foreign citizens become suspicious about possible hidden motives. To test this theory, we fielded a survey experiment involving divergent media frames of a real Russian medical donation to the U.S. early in the COVID-19 pandemic. We find that an adapted news article excerpt describing Russia's donation as genuine can decrease American citizens' support for sanctions on Russia. However, exposing respondents to information suggesting that Russia had political motivations for their donation is enough to cancel out the positive effect. Our findings suggest theoretical implications for the literature on foreign public opinion in international relations, particularly about the circumstances under which countries can manipulate the attitudes of other countries' citizens. Supplementary Information: The online version contains supplementary material available at 10.1007/s11109-022-09849-4.

Americans do not select their doctors based on race.

To what extent do Americans racially discriminate against doctors? While a large literature shows that racial biases pervade the American healthcare system, there has been no systematic examination of these biases in terms of who patients select for medical treatment. We examine this question in the context of the ongoing global COVID-19 pandemic, where a wealth of qualitative evidence suggests that discrimination against some historically marginalized communities, particularly Asians, has increased throughout the United States. Conducting a well-powered conjoint experiment with a national sample of 1,498 Americans, we find that respondents do not, on average, discriminate against Asian or doctors from other systematically minoritized groups. We also find no consistent evidence of treatment effect heterogeneity; Americans of all types appear not to care about the racial identity of their doctor, at least in our study. This finding has important implications for the potential limits of American prejudice.

Patient traits shape health-care stakeholders' choices on how to best allocate life-saving care.

During global pandemics, health-care decision makers often face critical shortages of life-saving medical equipment. How do medical stakeholders prioritize which patients are most deserving of scarce treatment? We report the results of three conjoint experiments conducted in the United States in 2020, testing for biases in US physicians', citizens' and elected politicians' preferences for scarce ventilator distribution. We found that all stakeholders prioritized younger patients and patients who had a higher probability of surviving with ventilator access. When patients' survivability was tied, physicians prioritized patients from racial/ethnic minorities (that is, Asian, Black and Hispanic patients) over all-else-equal white patients, religious minorities (that is, Muslim patients) over religious majority group members (that is, Catholic patients) and patients of lower socio-economic status over wealthier patients. The public also prioritized Black and Hispanic patients over white patients but were biased against religious minorities (that is, Atheist and Muslim patients) relative to religious majority group members. Elected politicians were also biased against Atheist patients. Our effects varied by political party-with Republican physicians, politicians and members of the public showing bias against religious minority patients and Democratic physicians showing preferential treatment of racial and religious minorities. Our results suggest that health-care stakeholders' personal biases impact decisions on who deserves life-saving medical equipment.

National identity predicts public health support during a global pandemic.

Changing collective behaviour and supporting non-pharmaceutical interventions is an important component in mitigating virus transmission during a pandemic. In a large international collaboration (Study 1, N = 49,968 across 67 countries), we investigated self-reported factors associated with public health behaviours (e.g., spatial distancing and stricter hygiene) and endorsed public policy interventions (e.g., closing bars and restaurants) during the early stage of the COVID-19 pandemic (April-May 2020). Respondents who reported identifying more strongly with their nation consistently reported greater engagement in public health behaviours and support for public health policies. Results were similar for representative and non-representative national samples. Study 2 (N = 42 countries) conceptually replicated the central finding using aggregate indices of national identity (obtained using the World Values Survey) and a measure of actual behaviour change during the pandemic (obtained from Google mobility reports). Higher levels of national identification prior to the pandemic predicted lower mobility during the early stage of the pandemic (r = -0.40). We discuss the potential implications of links between national identity, leadership, and public health for managing COVID-19 and future pandemics.

Are Americans less likely to reply to emails from Black people relative to White people?

In this article, we present the results from a large-scale field experiment designed to measure racial discrimination among the American public. We conducted an audit study on the general public-sending correspondence to 250,000 citizens randomly drawn from public voter registration lists. Our within-subjects experimental design tested the public's responsiveness to electronically delivered requests to volunteer their time to help with completing a simple task-taking a survey. We randomized whether the request came from either an ostensibly Black or an ostensibly White sender. We provide evidence that in electronic interactions, on average, the public is less likely to respond to emails from people they believe to be Black (rather than White). Our results give us a snapshot of a subtle form of racial bias that is systemic in the United States. What we term everyday or "paper cut" discrimination is exhibited by all racial/ethnic subgroups-outside of Black people themselves-and is present in all geographic regions in the United States. We benchmark paper cut discrimination among the public to estimates of discrimination among various groups of social elites. We show that discrimination among the public occurs more frequently than discrimination observed among elected officials and discrimination in higher education and the medical sector but simultaneously, less frequently than discrimination in housing and employment contexts. Our results provide a window into the discrimination that Black people in the United States face in day-to-day interactions with their fellow citizens.

Gender differences in the prosecution of police assault: Evidence from a natural experiment in Sweden.

States often seek to regulate the use of police force though citizen complaint systems. This paper examines these systems, specifically, whether patterns of bias found in other juridical contexts are mirrored in the adjudication of police assault. The analysis focuses on prosecutors as the first instance of adjudication who determine whether to move forward with investigation, effectively deciding the majority of cases. We ask whether prosecutor sex is associated with the probability that a police assault claim will be investigated. We leverage a natural experiment in Sweden where prosecutors are assigned through a modified lottery system, effectively randomizing appointment. Our findings suggest that prosecutor gender plays a role in judicial outcomes: women prosecutors are 16 percentage points more likely to investigate claims of police assault than their male counterparts. These findings have implications for scholars interested in state human rights abuses, democratic institutions, and judicial inequality.

Human Rights Texts: Converting Human Rights Primary Source Documents into Data.

We introduce and make publicly available a large corpus of digitized primary source human rights documents which are published annually by monitoring agencies that include Amnesty International, Human Rights Watch, the Lawyers Committee for Human Rights, and the United States Department of State. In addition to the digitized text, we also make available and describe document-term matrices, which are datasets that systematically organize the word counts from each unique document by each unique term within the corpus of human rights documents. To contextualize the importance of this corpus, we describe the development of coding procedures in the human rights community and several existing categorical indicators that have been created by human coding of the human rights documents contained in the corpus. We then discuss how the new human rights corpus and the existing human rights datasets can be used with a variety of statistical analyses and machine learning algorithms to help scholars understand how human rights practices and reporting have evolved over time. We close with a discussion of our plans for dataset maintenance, updating, and availability.

Short-term visual deprivation, tactile acuity, and haptic solid shape discrimination.

Previous psychophysical studies have reported conflicting results concerning the effects of short-term visual deprivation upon tactile acuity. Some studies have found that 45 to 90 minutes of total light deprivation produce significant improvements in participants' tactile acuity as measured with a grating orientation discrimination task. In contrast, a single 2011 study found no such improvement while attempting to replicate these earlier findings. A primary goal of the current experiment was to resolve this discrepancy in the literature by evaluating the effects of a 90-minute period of total light deprivation upon tactile grating orientation discrimination. We also evaluated the potential effect of short-term deprivation upon haptic 3-D shape discrimination using a set of naturally-shaped solid objects. According to previous research, short-term deprivation enhances performance in a tactile 2-D shape discrimination task - perhaps a similar improvement also occurs for haptic 3-D shape discrimination. The results of the current investigation demonstrate that not only does short-term visual deprivation not enhance tactile acuity, it additionally has no effect upon haptic 3-D shape discrimination. While visual deprivation had no effect in our study, there was a significant effect of experience and learning for the grating orientation task - the participants' tactile acuity improved over time, independent of whether they had, or had not, experienced visual deprivation.

Aging and the perception of slant from optical texture, motion parallax, and binocular disparity.

The ability of younger and older observers to perceive surface slant was investigated in four experiments. The surfaces possessed slants of 20 degrees, 35 degrees, 50 degrees, and 65 degrees, relative to the frontoparallel plane. The observers judged the slants using either a palm board (Experiments 1, 3, and 4) or magnitude estimation (Experiment 2). In Experiments 1-3, physically slanted surfaces were used (the surfaces possessed marble, granite, pebble, and circle textures), whereas computer-generated 3-D surfaces (defined by motion parallax and binocular disparity) were utilized in Experiment 4. The results showed that the younger and older observers' performance was essentially identical with regard to accuracy. The younger and older age groups, however, differed in terms of precision in Experiments 1 and 2: The judgments of the older observers were more variable across repeated trials. When taken as a whole, the results demonstrate that older observers (at least through the age of 83 years) can effectively extract information about slant in depth from optical patterns containing texture, motion parallax, or binocular disparity.

Modeling neuromuscular effects of ankle foot orthoses (AFOs) in computer simulations of gait.

Ankle foot orthoses (AFOs) provide immediate changes to gait kinematics and alter EMG-recorded muscle activity during gait; yet our understanding of neuromuscular adaptations while using AFOs remains incomplete. To address this, we have developed a tunable AFO model to predict torque from ankle angle and velocity and to identify plausible changes in muscle excitation and function in a walking simulation. Using a dynamometer in passive mode, we isolated flexion/extension torque of three polypropylene spring leaf AFOs at 5 degrees/s, 30 degrees/s and 120 degrees/s, from which a model of AFO torque as a function of deformation angle, velocity and size was derived with predictive ability of R2>0.9. The model coefficients did not vary linearly with size, illustrating the need to test AFO deformation response individually. We applied the tuned models to simulations of normal healthy gait to isolate AFO-induced neuromuscular changes. Compared to the No-AFO condition, AFO results show decreased net tibialis anterior excitation. Our results also show that net soleus excitation is not diminished with an AFO although soleus-induced ankle accelerations were reduced. With a tunable AFO model applied to walking simulations, we can quantify the contributions of muscle and orthosis to net joint torque and predict changes in neuromuscular control during walking.

Stereopsis and aging.

Three experiments investigated whether and to what extent increases in age affect the functionality of stereopsis. The observers' ages ranged from 18 to 83 years. The overall goal was to challenge the older stereoscopic visual system by utilizing high magnitudes of binocular disparity, ambiguous binocular disparity [cf., Julesz, B., & Chang, J. (1976). Interaction between pools of binocular disparity detectors tuned to different disparities. Biological Cybernetics, 22, 107-119], and by making binocular matching more difficult. In particular, Experiment 1 evaluated observers' abilities to discriminate ordinal depth differences away from the horopter using standing disparities of 6.5-46 min arc. Experiment 2 assessed observers' abilities to discriminate stereoscopic shape using line-element stereograms. The direction (crossed vs. uncrossed) and magnitude of the binocular disparity (13.7 and 51.5 min arc) were manipulated. Binocular matching was made more difficult by varying the orientations of corresponding line elements across the two eyes' views. The purpose of Experiment 3 was to determine whether the aging stereoscopic system can resolve ambiguous binocular disparities in a manner similar to that of younger observers. The results of all experiments demonstrated that older observers' stereoscopic vision is functionally comparable to that of younger observers in many respects. For example, both age groups exhibited a similar ability to discriminate depth and surface shape. The results also showed, however, that age-related differences in stereopsis do exist, and they become most noticeable when the older stereoscopic system is challenged by multiple simultaneous factors.

Poor shape perception is the reason reaches-to-grasp are visually guided online.

Both judgment studies and studies of feedforward reaching have shown that the visual perception of object distance, size, and shape are inaccurate. However, feedback has been shown to calibrate feedfoward reaches-to-grasp to make them accurate with respect to object distance and size. We now investigate whether shape perception (in particular, the aspect ratio of object depth to width) can be calibrated in the context of reaches-to-grasp. We used cylindrical objects with elliptical cross-sections of varying eccentricity. Our participants reached to grasp the width or the depth of these objects with the index finger and thumb. The maximum grasp aperture and the terminal grasp aperture were used to evaluate perception. Both occur before the hand has contacted an object. In Experiments 1 and 2, we investigated whether perceived shape is recalibrated by distorted haptic feedback. Although somewhat equivocal, the results suggest that it is not. In Experiment 3, we tested the accuracy of feedforward grasping with respect to shape with haptic feedback to allow calibration. Grasping was inaccurate in ways comparable to findings in shape perception judgment studies. In Experiment 4, we hypothesized that online guidance is needed for accurate grasping. Participants reached to grasp either with or without vision of the hand. The result was that the former was accurate, whereas the latter was not. We conclude that shape perception is not calibrated by feedback from reaches-to-grasp and that online visual guidance is required for accurate grasping because shape perception is poor.

Learning to perceive differences in solid shape through vision and touch.

A single experiment was designed to investigate perceptual learning and the discrimination of 3-D object shape. Ninety-six observers were presented with naturally shaped solid objects either visually, haptically, or across the modalities of vision and touch. The observers' task was to judge whether the two sequentially presented objects on any given trial possessed the same or different 3-D shapes. The results of the experiment revealed that significant perceptual learning occurred in all modality conditions, both unimodal and cross-modal. The amount of the observers' perceptual learning, as indexed by increases in hit rate and d', was similar for all of the modality conditions. The observers' hit rates were highest for the unimodal conditions and lowest in the cross-modal conditions. Lengthening the inter-stimulus interval from 3 to 15 s led to increases in hit rates and decreases in response bias. The results also revealed the existence of an asymmetry between two otherwise equivalent cross-modal conditions: in particular, the observers' perceptual sensitivity was higher for the vision-haptic condition and lower for the haptic-vision condition. In general, the results indicate that effective cross-modal shape comparisons can be made between the modalities of vision and active touch, but that complete information transfer does not occur.

Aging and the perception of 3-D shape from dynamic patterns of binocular disparity.

In two experiments, we investigated the ability of younger and older observers to perceive and discriminate 3-D shape from static and dynamic patterns of binocular disparity. In both experiments, the younger observers' discrimination accuracies were 20% higher than those of the older observers. Despite this quantitative difference, in all other respects the older observers performed similarly to the younger observers. Both age groups were similarly affected by changes in the magnitude of binocular disparity, by reductions in binocular correspondence, and by increases in the speed of stereoscopic motion. In addition, observers in both age groups exhibited an advantage in performance for dynamic stereograms when the patterns of binocular disparity contained significant amounts of correspondence "noise." The process of aging does affect stereopsis, but the effects are quantitative rather than qualitative.