Use of protracted CPAP as supportive treatment for COVID-19 pneumonitis and associated outcomes: a national cohort study

BACKGROUND

Continuous positive airway pressure (CPAP) has been increasingly deployed to manage patients with COVID-19 and acute respiratory failure, often for protracted periods. However, concerns about protracted CPAP have been raised. This study aimed to examine the use of CPAP for patients with COVID-19 and the outcomes after protracted use.

METHODS

This was a national cohort study of all adults admitted to Scottish critical care units with COVID-19 from March 1, 2020 to December 25, 2021 who received CPAP. Protracted CPAP was defined as ≥ 5 continuous days of CPAP. Outcomes included CPAP failure rate (institution of invasive mechanical ventilation [IMV] or death), mortality, and outcomes after institution of IMV. Multivariable logistic regression was performed to assess the impact of protracted CPAP on mortality after IMV.

RESULTS

A total of 1961 patients with COVID-19 received CPAP for COVID-19 pneumonitis, with 733 patients (37.4%) receiving protracted CPAP. CPAP failure occurred in 891 (45.4%): 544 patients (27.7%) received IMV and 347 patients (17.7%) died in critical care without IMV. Hospital mortality rate was 41.3% for the population. For patients who subsequently commenced IMV, hospital mortality was 58.7% for the standard duration CPAP group and 73.9% for the protracted duration CPAP group (P=0.003); however, there was no statistical difference in hospital mortality after adjustment for confounders (odds ratio 1.4, 95% confidence interval 0.84-2.33, P=0.195).

CONCLUSIONS

Protracted CPAP was used frequently for managing patients with COVID-19. Whilst it was not associated with worse outcomes for those patients who subsequently required IMV, this might be due to residual confounding and differences in processes of care.

Prevention of posttraumatic stress during inpatient rehabilitation post spinal cord injury: Study protocol for a randomized controlled trial of Brief Prolonged Exposure Therapy (Brief PE)

Background

Scant research has focused on posttraumatic stress disorder (PTSD) in the SCI population, despite high prevalence estimates. Fortunately, prolonged exposure therapy (PE) is a well-researched and highly effective treatment for PTSD. Our recent clinical trial showed that standard 12-session PE was effective for PTSD treatment among inpatients with SCI. Early intervention with brief PE (3-sessions) delivered in the emergency department has also been effective for PTSD prevention, but has not been tested among people post-SCI. Thus, we aim to conduct the first test of the Brief PE intervention to prevent PTSD among patients with SCI.

Methods

Adults who have experienced a SCI (N = 200) will be randomly assigned during inpatient rehabilitation to either: (a) 3 60-min sessions of Brief PE (intervention group) or (b) treatment as usual (control group).

Results

The primary outcome measure (PTSD symptoms measured by the PSSI-5) and secondary outcome measures (depression, anxiety, pain, quality of life, sleep disturbance, and resilience) will be assessed at baseline, 1-month, 3-months, and 6-months. Hierarchical linear modeling (HLM) will be used to evaluate the effectiveness of the PE intervention on PTSD and secondary outcomes. Descriptive statistics will examine feasibility and will include the number of participants enrolled, the number of sessions completed, fidelity of Brief PE delivery, and average scores for difficulty and helpfulness of the intervention scales for those randomized to intervention.

Conclusions

Successful completion of this study will provide an evidence-based program to alleviate posttraumatic distress post spinal cord injury and prevent long-term development of PTSD.

Acceptance of mixed gambles is sensitive to the range of gains and losses experienced, and estimates of lambda (λ) are not a reliable measure of loss aversion: Reply to André and de Langhe (2020)

Walasek and Stewart (2015) demonstrated that loss aversion estimated from fitting accept–reject choice data from a set of 50–50 gambles can be made to disappear or even reverse by manipulating the range of gains and losses experienced in different conditions. André and de Langhe (2020) critique this conclusion because in estimating loss aversion on different choice sets, Walasek and Stewart (2015) have violated measurement invariance. They show, and we agree, that when loss aversion is estimated on the choices common to all conditions, there is no difference in prospect theory’s λ parameter. But there are two problems here. First, while there are no differences in λs across conditions, there are very large differences in the proportion of the common gambles that are accepted, which André and de Langhe chose not to report. These choice proportion differences are consistent with decision by sampling (but are inconsistent with prospect theory or any of the alternative mechanisms proposed by André & de Langhe, 2020). Second, we demonstrate a much more general problem related to the issue of measurement invariance: that λ estimated from the accept–reject choices is extremely unreliable and does not generalize even across random splits within large, balanced choice sets. It is therefore not possible to determine whether differences in choice proportions are due to loss aversion or to a bias in accepting or rejecting mixed gambles. We conclude that context has large effects on the acceptance of mixed gambles and that it is futile to estimate λ from accept–reject choices.

Complementary pre-screening strategies to uncover hidden prodromal and mild Alzheimer's disease: Results from the MOPEAD project

Introduction

The Models of Patient Engagement for Alzheimer's Disease (MOPEAD) project was conceived to explore innovative complementary strategies to uncover hidden prodromal and mild Alzheimer's disease (AD) dementia cases and to raise awareness both in the general public and among health professionals about the importance of early diagnosis.

Methods

Four different strategies or RUNs were used: (a) a web‐based (WB) prescreening tool, (2) an open house initiative (OHI), (3) a primary care–based protocol for early detection of cognitive decline (PC), and (4) a tertiary care–based pre‐screening at diabetologist clinics (DC).

Results

A total of 1129 patients at high risk of having prodromal AD or dementia were identified of 2847 pre‐screened individuals (39.7%). The corresponding proportion for the different initiatives were 36.8% (WB), 35.6% (OHI), 44.4% (PC), and 58.3% (DC).

Conclusion

These four complementary pre‐screening strategies were useful for identifying individuals at high risk of having prodromal or mild AD.

Officer bias, over-patrolling and ethnic disparities in stop and search

Black and Asian people in the United Kingdom are more likely to be stopped and searched by police than White people. Following a panel of 36,000 searches by 1,100 police officers at a major English police force, we provide officer-specific measures of over-searching relative to two baselines: the ethnic composition of crime suspects officers interact with and the ethnic composition of the areas they patrol. We show that the vast majority of officers over-search ethnic minorities against both baselines. But we also find that the over-searching by individual officers cannot account for all of the over-representation of ethnic minorities in stop and search: over-patrolling of minority areas is also a key factor. Decomposing the overall search bias, we find that the over-representation of Asian people in stop and search is primarily accounted for by over-patrolling, while the over-representation of Black people is a combination of officer and patrol effects, with the larger contribution coming from biases of officers.

Neutropenia in patients under treatment with clozapine and COVID-19 infection

Introduction

Clozapine is among the most effective antipsychotics used for treatment resistant schizophrenia. Adverse reactions to clozapine include neutropenia. Case series report that clozapine-treated patients with COVID-19 have no documented neutropenia.

Objectives

We sought to investigate the potential adverse effect of coronavirus disease (COVID-19) in patients taking clozapine.

Methods

We retrospectively inspected data of 13 consecutive patients on clozapine, admitted to Highgate Mental Health Centre -Camden & Islington NHS Foundation Trust between March and June 2020. Selection was based on their COVID-19 symptoms presentation and/or COVID-19 positive test. We used a linear regression model with COVID status as independent variable and absolute neutrophil count (ANC) as dependent variable to inform about a correlation between COVID-19 status and neutrophil count. STATA was used for statistics.

Results

We collected data on thirteen patients of which nine were male. The median age was of 41.97 years; six subjects were Black, three were Asian and four were White Caucasian. Ten subjects tested positive to COVID-19 and 3 were suspected cases -these latter were excluded from stastical analysis. During COVID-19 infection, neutrophils count (ANC) dropped significantly to 4.215 from a baseline value of 5.337. The beta values of 0.83 shows that ANC declined significantly during COVID-19 infection (p =<.0001, R2 = 95%). In three of thirteen patients, ANC drop was significant and changed the patients’ monitoring status from green to amber and required frequent blood tests.

Conclusions

Clinicians should bear in mind that a significant drop in neutrophils count may occur in COVID-19 -infected patients taking clozapine.

Disclosure

No significant relationships.

The association between gambling and financial, social and health outcomes in big financial data

Gambling is an ordinary pastime for some people, but is associated with addiction and harmful outcomes for others. Evidence of these harms is limited to small-sample, cross-sectional self-reports, such as prevalence surveys. We examine the association between gambling as a proportion of monthly income and 31 financial, social and health outcomes using anonymous data provided by a UK retail bank, aggregated for up to 6.5 million individuals over up to 7 years. Gambling is associated with higher financial distress and lower financial inclusion and planning, and with negative lifestyle, health, well-being and leisure outcomes. Gambling is associated with higher rates of future unemployment and physical disability and, at the highest levels, with substantially increased mortality. Gambling is persistent over time, growing over the sample period, and has higher negative associations among the heaviest gamblers. Our findings inform the debate over the relationship between gambling and life experiences across the population.

Clozapine, neutropenia and Covid-19: should clinicians be concerned? 3 months report

Background

Clozapine is among the most effective antipsychotics used for treatment resistant schizophrenia. Adverse reactions to clozapine include neutropenia. In March 2020, at the start of the Coronavirus −19 pandemic, clinicians raised concerns regarding continuation of antipsychotic treatment, and specifically of clozapine, in patients with coronavirus disease. We aimed here at providing a short report focusing on the association between neutropenia and clozapine in a case series of psychiatric inpatients diagnosed with COVID-19.

Patients & methods

We retrospectively inspected data of 10 patients on clozapine, admitted to Highgate Mental Health Centre, Camden & Islington NHS Foundation Trust, between March and July 2020; selection was based on their COVID-19 positive PCR test. We used a linear regression model to estimate whether there was a significant drop in the neutrophil count during SARS-CoV-2 infection.

The analysis was done in R using a linear regression to the origin.

Results

Data were collected on 10 patients, of which 7 were males. During COVID-19 infection, neutrophils’ count (ANC) was 4.13 ​× ​10⁹/l (SD ​= ​2.70) which constituted a significant drop from a baseline value of 5.2 ​× ​10⁹/l (SD ​= ​2.24). The mean relative reduction in ANC was −0.2729 (SD ​= ​0.1666). The beta value of 0.8377 obtained with the linear regression showed that ANC values during SARS-CoV-2 infection were 83.77% of the baseline ANC showing that within the two time points there was a decrease of 16.23%. The linear regression had a pvalue ​= ​8.96 ​× ​10^–8 and an adjusted R² of 95.94% which shows that the variability of the data is very well explained by the model. We also compared baseline ANC with ANC values approximately a month after resolution of the infection and results indicate that ANC values return to a 95% of baseline.

Conclusions

Clinicians should bear in mind that a significant drop in neutrophils’ count may occur in patients taking clozapine and affected from a SARS-CoV-2 infectionand that this drop is only transitory.

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Clinicians raised concerns regarding continuation of clozapine in patients with coronavirus disease.

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We inspected data of patients COVID positive taking clozapine between March and July 2020.

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Absolute Neutrophil Count (ANC) dropped significantly with a 16.23% decrease of baseline values.

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Following resolution of COVID-19 infection ANC values subsequently increased up to 95% of the pre-infection values.

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A significant drop in neutrophils’ count may occur. However, this is likely to normalise once the infection is resolved.

The role of alcohol in the link between national football (soccer) tournaments and domestic abuse - Evidence from England

Domestic abuse is increasingly recognised as a serious public health concern worldwide. Previous research has suggested a link between national football (soccer) tournaments and domestic abuse. While hypothesized to be a significant factor, the role alcohol plays in this relationship has not yet been explored quantitatively. In this study, using 10 years' worth of crime data (from 2010 to 2019) from the second largest police force in England (West Midlands Police), we explored the effect of England draws, losses, and wins in national football tournaments on the number of alcohol and non-alcohol-related domestic abuse cases reported to the police. Results from a series of negative binomial regression analyses show that the number of reported alcohol-related domestic abuse cases increases by 47%, 95% confidence interval [26%-71%], following an England football victory. This effect is limited to alcohol-related cases. The estimate translates into a 0.53, 95% CI [0.3-0.8], increase in the daily rate of alcohol-related cases per 100,000 individuals. The England win effect survives various robustness checks (including the re-analysis of a dataset from another geographical area in England), and its time course is strongly consistent with a causal link between England's football victories and an increase in alcohol-related domestic abuse. We also found a comparable increase in the number of other (not classified as domestic abuse) alcohol-related violent crimes on England win days. Further research is required to understand the exact causal pathway between national football tournaments, alcohol consumption, and violent behaviours in domestic settings.

Clinical presentation, sonographic features and treatment options of segmental stiff skin syndrome

Segmental stiff skin syndrome is a rare genetic connective tissue disease, which is often misdiagnosed. High-frequency ultrasonography can represent a useful clinical adjunct in the differential diagnosis of this condition, in conjunction with the clinical and histopathological findings. Treatment options are limited and evidence is scarce. We present the clinical, sonographic and histological features of five paediatric patients diagnosed at our institution and discuss their response to treatment.

A dilution effect without dilution: When missing evidence, not non-diagnostic evidence, is judged inaccurately

When asked to combine two pieces of evidence, one diagnostic and one non-diagnostic, people show a dilution effect: the addition of non-diagnostic evidence dilutes the overall strength of the evidence. This non-normative effect has been found in a variety of tasks and has been taken as evidence that people inappropriately combine information. In a series of five experiments, we found the dilution effect, but surprisingly it was not due to the inaccurate combination of diagnostic and non-diagnostic information. Because we have objectively correct answers for our task, we could see that participants were relatively accurate in judging diagnostic evidence combined with non-diagnostic evidence, but overestimated the strength of diagnostic evidence alone. This meant that the dilution effect - the gap between diagnostic evidence alone and diagnostic evidence combined with non-diagnostic evidence - was not caused by dilution. We hypothesized that participants were filling in "missing" evidence in a biased fashion when presented with diagnostic evidence alone. This hypothesis best explained the experimental results.

Multialternative decision by sampling: A model of decision making constrained by process data

Sequential sampling of evidence, or evidence accumulation, has been implemented in a variety of models to explain a range of multialternative choice phenomena. But the existing models do not agree on what, exactly, the evidence is that is accumulated. They also do not agree on how this evidence is accumulated. In this article, we use findings from process-tracing studies to constrain the evidence accumulation process. With these constraints, we extend the decision by sampling model and propose the multialternative decision by sampling (MDbS) model. In MDbS, the evidence accumulated is outcomes of pairwise ordinal comparisons between attribute values. MDbS provides a quantitative account of the attraction, compromise, and similarity effects equal to that of other models, and captures a wider range of empirical phenomena than other models.

Context-dependent sensitivity to losses: Range and skew manipulations

The assumption that losses loom larger than gains is widely used to explain many behavioral phenomena in judgment and decision-making. It is also generally accepted that loss aversion is a stable, traitlike individual difference characterizing people’s sensitivity to gains and losses. This interpretation was recently challenged by Walasek and Stewart (2015), who showed that by manipulating the range of the gains and losses used in the accept−reject task it is possible to find loss aversion, loss neutrality, and a reversal of loss aversion. Here, we reexamined the claim that these context effects arise as a result of people being sensitive to the rank position of a given gain among other gains and the rank position of a loss among other losses. We used skewed distributions of outcomes to manipulate the rank position of gains and losses while keeping the range of possible outcomes constant. We found a small but robust effect of skew on the propensity to accept mixed gambles. We compared the sizes of skew and range effects and found that they are of similar magnitude but that the range effects are smaller than those reported by Walasek and Stewart. We were able to attenuate loss aversion, but we were not able to replicate Walasek and Stewart’s reversal of loss aversion. We conclude that rank effects are, at least in part, responsible for the loss aversion seen in the accept−reject task.

Dissimilarity is used as Evidence of Category Membership in Multidimensional Perceptual Categorization: A Test of the Similarity–Dissimilarity Generalized Context Model

In exemplar models of categorization, the similarity between an exemplar and category members constitutes evidence that the exemplar belongs to the category. We test the possibility that the dissimilarity to members of competing categories also contributes to this evidence. Data were collected from two 2-dimensional perceptual categorization experiments, one with lines varying in orientation and length and the other with coloured patches varying in saturation and brightness. Model fits of the similarity–dissimilarity generalized context model were used to compare a model where only similarity was used with a model where both similarity and dissimilarity were used. For the majority of participants the similarity–dissimilarity model provided both a significantly better fit and better generalization, suggesting that people do also use dissimilarity as evidence.

Crowdsourcing Samples in Cognitive Science

Crowdsourcing data collection from research participants recruited from online labor markets is now common in cognitive science. We review who is in the crowd and who can be reached by the average laboratory. We discuss reproducibility and review some recent methodological innovations for online experiments. We consider the design of research studies and arising ethical issues. We review how to code experiments for the web, what is known about video and audio presentation, and the measurement of reaction times. We close with comments about the high levels of experience of many participants and an emerging tragedy of the commons.

Three-dimensional changes in head shape after extended sagittal strip craniectomy with wedge ostectomies and helmet therapy

OBJECTIVE Outcome studies for sagittal strip craniectomy have largely relied on the 2D measure of the cephalic index (CI) as the primary indicator of head shape. The goal of this study was to measure the 2D and 3D changes in head shape that occur after sagittal strip craniectomy and postoperative helmet therapy. METHODS The authors performed a retrospective review of patients treated with sagittal strip craniectomy at their institution between January 2012 and October 2015. Inclusion criteria were as follows: 1) isolated sagittal synostosis; 2) age at surgery < 200 days; and 3) helmet management by a single orthotist. The CI was calculated from 3D images. Color maps and dot maps were generated from 3D images to demonstrate the regional differences in the magnitude of change in head shape over time. RESULTS Twenty-one patients met the study inclusion criteria. The mean CI was 71.9 (range 63.0-77.9) preoperatively and 81.1 (range 73.0-89.8) at the end of treatment. The mean time to stabilization of the CI after surgery was 57.2 ± 32.7 days. The mean maximum distances between the surfaces of the preoperative and 1-week postoperative and between the surfaces of the preoperative and end-of-treatment 3D images were 13.0 ± 4.1 mm and 24.71 ± 6.83 mm, respectively. The zone of maximum change was distributed equally in the transverse and vertical dimensions of the posterior vault. CONCLUSIONS The CI normalizes rapidly after sagittal strip craniectomy (57.2 days), with equal distribution of the change in CI occurring before and during helmet therapy. Three-dimensional analysis revealed significant vertical and transverse expansion of the posterior cranial vault. Further studies are needed to assess the 3D changes that occur after other sagittal strip craniectomy techniques.

The risk of violence associated with novel psychoactive substance misuse in patients presenting to acute mental health services

Novel psychoactive substance (NPS) availability is increasing at a phenomenal rate and so is their associated misuse. Currently, the harms associated with NPS misuse are unclear. This report presents the initial findings of a continuing study looking into the impact of NPS misuse on admissions to an acute mental health facility in London. Violence preadmission and violence during admission have been found to be significant in NPS misusers compared to non-NPS substance misusers. Our findings have important consequences for acute mental health, emergency, and public health services. NPS misusers require specific assessment and risk management to reduce the risk of violence towards others.

Syringomyelic Neuropathic Arthropathy of the Elbow

Neuropathic Arthropathy or Charcot joint is a progressive, destructive arthritis that is associated with an underlying neurological disorder. We present a case of a 30 year-old male who, three years prior, had ruptured his right distal biceps tendon with subsequent development of a deep infection. At representation, the patient's clinical picture was consistent with the re-emergence of a deep elbow infection. Laboratory testing found no evidence of infection. Magnetic Resonance Imaging (MRI) of the patient's spine revealed a syringomyelia and a NA was diagnosed. The purpose of this report is to raise awareness of a unique presentation of a rare clinical condition in the early stages of the disease. Neuropathic Arthropathy (NA) is a rare disorder which typically affects the joints of the lower limb. Involvement of the upper limb is uncommon. Among patients with NA, the elbow joint is thought to be affected in only 3% of cases. NA of the elbow as a presenting symptom of syringomyelia is extremely rare. We describe a unique case of NA of the right elbow preceded by a septic arthritis of the same joint. The purpose of this case report is to raise awareness of an uncommon pathology in its early stages where outcomes may be influenced by early diagnosis and management.

Implications of Visual Attention Phenomena for Models of Preferential Choice

We use computational modeling to examine the ability of evidence accumulation models to produce the reaction time (RT) distributions and attentional biases found in behavioral and eye-tracking research. We focus on simulating RTs and attention in binary choice with particular emphasis on whether different models can predict the late onset bias (LOB), commonly found in eye movements during choice (sometimes called the gaze cascade). The first finding is that this bias is predicted by models even when attention is entirely random and independent of the choice process. This shows that the LOB is not evidence of a feedback loop between evidence accumulation and attention. Second, we examine models with a relative evidence decision rule and an absolute evidence rule. In the relative models a decision is made once the difference in evidence accumulated for 2 items reaches a threshold. In the absolute models, a decision is made once 1 item accumulates a certain amount of evidence, independently of how much is accumulated for a competitor. Our core result is simple-the existence of the late onset gaze bias to the option ultimately chosen, together with a positively skewed RT distribution means that the stopping rule must be relative not absolute. A large scale grid search of parameter space shows that absolute threshold models struggle to predict these phenomena even when incorporating evidence decay and assumptions of either mutual inhibition or feedforward inhibition.

Eye Movements in Strategic Choice

In risky and other multiattribute choices, the process of choosing is well described by random walk or drift diffusion models in which evidence is accumulated over time to threshold. In strategic choices, level‐k and cognitive hierarchy models have been offered as accounts of the choice process, in which people simulate the choice processes of their opponents or partners. We recorded the eye movements in 2 × 2 symmetric games including dominance‐solvable games like prisoner's dilemma and asymmetric coordination games like stag hunt and hawk–dove. The evidence was most consistent with the accumulation of payoff differences over time: we found longer duration choices with more fixations when payoffs differences were more finely balanced, an emerging bias to gaze more at the payoffs for the action ultimately chosen, and that a simple count of transitions between payoffs—whether or not the comparison is strategically informative—was strongly associated with the final choice. The accumulator models do account for these strategic choice process measures, but the level‐k and cognitive hierarchy models do not. © 2015 The Authors. Journal of Behavioral Decision Making published by John Wiley & Sons Ltd.

Modulating effects of WT1 on interferon-β-vitamin D association in MS

OBJECTIVE

To investigate whether those genes involved in the vitamin D pathway modulate the relationship between 25-hydroxyvitamin D (25(OH)D) and IFN-β, the relationship between IFN-β and sun in predicting 25(OH)D, and the interaction between IFN-β and 25(OH)D in modulating relapse risk in patients with MS.

METHODS

Prospective cohort study of 169 participants with MS and genotype data followed 2002-2005. Gene-IFN-β and gene-IFN-β-sun interactions predicting 25(OH)D evaluated by multilevel mixed-effects linear regression. Gene-IFN-β interactions with 25(OH)D in modulating in relapse risk assessed using survival analysis.

RESULTS

The cohort was 71.6% female and of mean age 47.8. Two-independent intronic genotyped SNPs (rs10767935 and rs5030244) in WT1 significantly modified the IFN-β-25(OH)D association after adjustment (P(interaction) = 0.001, 0.0002; P(adj) = 0.003, 0.006, respectively). There was a marked difference in the interaction between self-reported sun exposure and IFN-β in predicting 25(OH)D by level of rs10767935, although this did not reach statistical significance. No SNPs modified the interaction between IFN-β and 25(OH)D in predicting relapse.

CONCLUSIONS

We have demonstrated that two-independent SNPs (rs10767935 and rs5030244) in WT1 modified the IFN-β-25(OH)D association in patients with MS. Some evidence was shown for a difference in the sun-IFN-β-25(OH)D association by level of rs10767935. These findings indicate that WT1 variants may play a role in altering the effects of IFN-β on vitamin D in MS.

Eye Movements in Risky Choice

We asked participants to make simple risky choices while we recorded their eye movements. We built a complete statistical model of the eye movements and found very little systematic variation in eye movements over the time course of a choice or across the different choices. The only exceptions were finding more (of the same) eye movements when choice options were similar, and an emerging gaze bias in which people looked more at the gamble they ultimately chose. These findings are inconsistent with prospect theory, the priority heuristic, or decision field theory. However, the eye movements made during a choice have a large relationship with the final choice, and this is mostly independent from the contribution of the actual attribute values in the choice options. That is, eye movements tell us not just about the processing of attribute values but also are independently associated with choice. The pattern is simple-people choose the gamble they look at more often, independently of the actual numbers they see-and this pattern is simpler than predicted by decision field theory, decision by sampling, and the parallel constraint satisfaction model. © 2015 The Authors. Journal of Behavioral Decision Making published by John Wiley & Sons Ltd.

How to make loss aversion disappear and reverse: tests of the decision by sampling origin of loss aversion

One of the most robust empirical findings in the behavioral sciences is loss aversion—the finding that losses loom larger than gains. We offer a new psychological explanation of the origins of loss aversion in which loss aversion emerges from differences in the distribution of gains and losses people experience. In 4 experiments, we tested this proposition by manipulating the range of gains and losses that individuals saw during the process of eliciting their loss aversion. We were able to find loss aversion, loss neutrality, and even the reverse of loss aversion.

In the attraction, compromise, and similarity effects, alternatives are repeatedly compared in pairs on single dimensions

In multi-alternative choice, the attraction, compromise, and similarity effects demonstrate that the value of an alternative is not independent of the other alternatives in the choice-set. Rather, these effects suggest that a choice is reached through the comparison of alternatives. We investigated exactly how alternatives are compared against each other using eye-movement data. The results indicate that a series of comparisons is made in each choice, with a pair of alternatives compared on a single attribute dimension in each comparison. We conclude that psychological models of choice should be based on these single-attribute pairwise comparisons.

Characterizing the time-perspective of nations with search engine query data

Vast quantities of data on human behavior are being created by our everyday internet usage. Building upon a recent study by Preis, Moat, Stanley, and Bishop (2012), we used search engine query data to construct measures of the time-perspective of nations, and tested these measures against per-capita gross domestic product (GDP). The results indicate that nations with higher per-capita GDP are more focused on the future and less on the past, and that when these nations do focus on the past, it is more likely to be the distant past. These results demonstrate the viability of using nation-level data to build psychological constructs.