The causes of government and the consequences for growth and well-being

Using a large cross-country data set, the authors examine the factors that cause governments to grow, and analyze how the size of government affects growth, whether measured as income growth or other measures of well-being, such as infant mortality and life expectancy. They find no robust link between government size and per capita income. The factors they find to be important in explaining government size are relative prices, the age-dependency ratio, how long a country has been independent, relative political freedom, and openness in trade. Their results also partially support the view that governments use consumption to buffer external risk, especially in low-income countries. As for how government size affects growth, they find a robust and significant negative relationship between growth and government size, as measured by consumption. Policy distortions, predictably, also have a negative effect on growth. But the positive effects of well-functioning institutions and high quality in government bureaucracies can offset the negative influence of large government size alone. Finally, they find that social-sector spending can exert a positive influence by reducing infant mortality and raising life expectancy. Better income distribution, higher per capita income, higher per capita income growth, and more political freedom have the same positive effect on those two measures of well-being.Environmental Economics&Policies,Economic Theory&Research,National Governance,Payment Systems&Infrastructure,Knowledge Economy,Knowledge Economy,Environmental Economics&Policies,National Governance,Economic Theory&Research,Inequality

Event-based modelling in temporal lobe epilepsy demonstrates progressive atrophy from cross-sectional data

OBJECTIVE: Recent work has shown that people with common epilepsies have characteristic patterns of cortical thinning, and that these changes may be progressive over time. Leveraging a large multi-centre cross-sectional cohort, we investigated whether regional morphometric changes occur in a sequential manner, and whether these changes in people with mesial temporal lobe epilepsy and hippocampal sclerosis (MTLE-HS) correlate with clinical features. METHODS: We extracted regional measures of cortical thickness, surface area and subcortical brain volumes from T1-weighted (T1W) MRI scans collected by the ENIGMA-Epilepsy consortium, comprising 804 people with MTLE-HS and 1,625 healthy controls from 25 centres. Features with a moderate case-control effect size (Cohen's d≥0.5) were used to train an Event-Based Model (EBM), which estimates a sequence of disease-specific biomarker changes from cross-sectional data and assigns a biomarker-based fine-grained disease stage to individual patients. We tested for associations between EBM disease stage and duration of epilepsy, age of onset and anti-seizure medicine (ASM) resistance. RESULTS: In MTLE-HS, decrease in ipsilateral hippocampal volume along with increased asymmetry in hippocampal volume was followed by reduced thickness in neocortical regions, reduction in ipsilateral thalamus volume and, finally, increase in ipsilateral lateral ventricle volume. EBM stage was correlated to duration of illness (Spearman's ρ=0.293, p=7.03x10-16 ), age of onset (ρ=-0.18, p=9.82x10-7 ) and ASM resistance (AUC=0.59, p=0.043, Mann-Whitney U test). However, associations were driven by cases assigned to EBM stage zero, which represents MTLE-HS with mild or non-detectable abnormality on T1W MRI. SIGNIFICANCE: From cross-sectional MRI, we reconstructed a disease progression model that highlights a sequence of MRI changes that aligns with previous longitudinal studies. This model could be used to stage MTLE-HS subjects in other cohorts and help establish connections between imaging-based progression staging and clinical features

White matter abnormalities across different epilepsy syndromes in adults: an ENIGMA-Epilepsy study

The epilepsies are commonly accompanied by widespread abnormalities in cerebral white matter. ENIGMA-Epilepsy is a large quantitative brain imaging consortium, aggregating data to investigate patterns of neuroimaging abnormalities in common epilepsy syndromes, including temporal lobe epilepsy, extratemporal epilepsy, and genetic generalized epilepsy. Our goal was to rank the most robust white matter microstructural differences across and within syndromes in a multicentre sample of adult epilepsy patients. Diffusion-weighted MRI data were analysed from 1069 healthy controls and 1249 patients: temporal lobe epilepsy with hippocampal sclerosis (n = 599), temporal lobe epilepsy with normal MRI (n = 275), genetic generalized epilepsy (n = 182) and non-lesional extratemporal epilepsy (n = 193). A harmonized protocol using tract-based spatial statistics was used to derive skeletonized maps of fractional anisotropy and mean diffusivity for each participant, and fibre tracts were segmented using a diffusion MRI atlas. Data were harmonized to correct for scanner-specific variations in diffusion measures using a batch-effect correction tool (ComBat). Analyses of covariance, adjusting for age and sex, examined differences between each epilepsy syndrome and controls for each white matter tract (Bonferroni corrected at P < 0.001). Across ‘all epilepsies’ lower fractional anisotropy was observed in most fibre tracts with small to medium effect sizes, especially in the corpus callosum, cingulum and external capsule. There were also less robust increases in mean diffusivity. Syndrome-specific fractional anisotropy and mean diffusivity differences were most pronounced in patients with hippocampal sclerosis in the ipsilateral parahippocampal cingulum and external capsule, with smaller effects across most other tracts. Individuals with temporal lobe epilepsy and normal MRI showed a similar pattern of greater ipsilateral than contralateral abnormalities, but less marked than those in patients with hippocampal sclerosis. Patients with generalized and extratemporal epilepsies had pronounced reductions in fractional anisotropy in the corpus callosum, corona radiata and external capsule, and increased mean diffusivity of the anterior corona radiata. Earlier age of seizure onset and longer disease duration were associated with a greater extent of diffusion abnormalities in patients with hippocampal sclerosis. We demonstrate microstructural abnormalities across major association, commissural, and projection fibres in a large multicentre study of epilepsy. Overall, patients with epilepsy showed white matter abnormalities in the corpus callosum, cingulum and external capsule, with differing severity across epilepsy syndromes. These data further define the spectrum of white matter abnormalities in common epilepsy syndromes, yielding more detailed insights into pathological substrates that may explain cognitive and psychiatric co-morbidities and be used to guide biomarker studies of treatment outcomes and/or genetic research

Topographic divergence of atypical cortical asymmetry and atrophy patterns in temporal lobe epilepsy

Temporal lobe epilepsy, a common drug-resistant epilepsy in adults, is primarily a limbic network disorder associated with predominant unilateral hippocampal pathology. Structural MRI has provided an in vivo window into whole-brain grey matter structural alterations in temporal lobe epilepsy relative to controls, by either mapping (i) atypical inter-hemispheric asymmetry; or (ii) regional atrophy. However, similarities and differences of both atypical asymmetry and regional atrophy measures have not been systematically investigated. Here, we addressed this gap using the multisite ENIGMA-Epilepsy dataset comprising MRI brain morphological measures in 732 temporal lobe epilepsy patients and 1418 healthy controls. We compared spatial distributions of grey matter asymmetry and atrophy in temporal lobe epilepsy, contextualized their topographies relative to spatial gradients in cortical microstructure and functional connectivity calculated using 207 healthy controls obtained from Human Connectome Project and an independent dataset containing 23 temporal lobe epilepsy patients and 53 healthy controls and examined clinical associations using machine learning. We identified a marked divergence in the spatial distribution of atypical inter-hemispheric asymmetry and regional atrophy mapping. The former revealed a temporo-limbic disease signature while the latter showed diffuse and bilateral patterns. Our findings were robust across individual sites and patients. Cortical atrophy was significantly correlated with disease duration and age at seizure onset, while degrees of asymmetry did not show a significant relationship to these clinical variables. Our findings highlight that the mapping of atypical inter-hemispheric asymmetry and regional atrophy tap into two complementary aspects of temporal lobe epilepsy-related pathology, with the former revealing primary substrates in ipsilateral limbic circuits and the latter capturing bilateral disease effects. These findings refine our notion of the neuropathology of temporal lobe epilepsy and may inform future discovery and validation of complementary MRI biomarkers in temporal lobe epilepsy.11Nsciescopu

Benefit Incidence of Public Education and Health Spending Worldwide: Evidence From A New Database

This paper compiles a new database on the benefit incidence of public education and health spending covering 56 countries over 1960–2000. The database represents a significant improvement in quality and coverage over existing compilations. First, it covers a broader set of industrial and developing countries. Second, it provides information on benefit incidence over time. Third, the database reports auxiliary identifiers of a benefit incidence analysis, allowing for consistent comparisons within and across countries. The database is used to ascertain which income groups tend to benefit more from social spending. We also explore the relationship between benefit incidence on the one hand and indicators of access to education and health services and social outcomes on the other, using simple measures of association. The paper explores policy implications of these findings. Researchers interested in analyzing the effectiveness of social spending and the role of government would find the database an invaluable tool for further analyses.National Government Expenditures and Related Policies, benefit incidence, public spending on education and health, targeting, progressivity

Disarming fears of diversity: ethnic heterogeneity and state militarization, 1988-2002

This study investigates whether ethnic and other forms of social diversity affect militarization of society. Recent scholarship in economics finds that high diversity leads to lower provision of public goods. At the same time, many conflict studies find that highly diverse societies face a lower risk of civil war, as opposed to relatively more homogenous populations. The authors explore whether diversity prompts governments to militarize heavily in order to prevent armed conflict, which would then crowd out spending on other public goods in a `guns versus butter' trade-off. Thus, `preventive militarization' would explain both outcomes. Yet the authors find the opposite: higher levels of ethnic diversity predict lower levels of militarization. If high diversity lowers the hazard of civil war, as many find, then it does not happen via preventive militarization. If diverse societies spend less on public goods, then this is not because they are crowded out by security spending. The results support those who suggest that diversity may, in fact, pose a lower security threat to states, since it is highly likely that states facing potential social strife would prioritize state militarization