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Background: Findings of reward disturbances in unaffected relatives of patients with schizophrenia suggest reward disturbances as an endophenotype for schizophrenia. Twin studies, where 1 twin has been diagnosed with a schizophrenia spectrum disorder, can further explore this. Methods: We used Danish registries to identify twin pairs with at least 1 twin having a schizophrenia spectrum disorder diagnosis and control twin pairs matched on age, sex, and zygosity. The analyses included data from 34 unaffected co-twins (16 females), 42 probands with schizophrenia spectrum disorder (17 females), and 83 control twins (42 females). Participants performed a modified incentive delay task during functional magnetic resonance imaging. Whole-brain group differences were analyzed by performing comparisons between co-twins and control twins. Correlations with cognitive flexibility were tested. Results: Compared with control twins, co-twins showed no differences in striatal regions, but increased signal in the dorsolateral prefrontal cortex (DLPFC) during missed target contrast was observed. In co-twins, increased DLPFC signal was associated with lower intra-extra dimensional set-shifting scores indicative of higher cognitive flexibility. Conclusions: Unaffected co-twins did not have decreased striatal activity during anticipation as previously reported for patients with schizophrenia. Instead, they showed increased activity in the DLPFC during evaluation of missed target contrast, which correlated with their level of cognitive flexibility. Unaffected co-twins had no diagnosis at a mean age of 40 years. This could indicate that greater cognitive flexibility and increased activity in the right DLPFC during processing of unexpected negative outcome represents a compensatory resilience mechanism in predisposed twins.

Background: Findings of reward disturbances in unaffected relatives of patients with schizophrenia suggest reward disturbances as an endophenotype for schizophrenia. Twin studies, where 1 twin has been diagnosed with a schizophrenia spectrum disorder, can further explore this. Methods: We used Danish registries to identify twin pairs with at least 1 twin having a schizophrenia spectrum disorder diagnosis and control twin pairs matched on age, sex, and zygosity. The analyses included data from 34 unaffected co-twins (16 females), 42 probands with schizophrenia spectrum disorder (17 females), and 83 control twins (42 females). Participants performed a modified incentive delay task during functional magnetic resonance imaging. Whole-brain group differences were analyzed by performing comparisons between co-twins and control twins. Correlations with cognitive flexibility were tested. Results: Compared with control twins, co-twins showed no differences in striatal regions, but increased signal in the dorsolateral prefrontal cortex (DLPFC) during missed target contrast was observed. In co-twins, increased DLPFC signal was associated with lower intra-extra dimensional set-shifting scores indicative of higher cognitive flexibility. Conclusions: Unaffected co-twins did not have decreased striatal activity during anticipation as previously reported for patients with schizophrenia. Instead, they showed increased activity in the DLPFC during evaluation of missed target contrast, which correlated with their level of cognitive flexibility. Unaffected co-twins had no diagnosis at a mean age of 40 years. This could indicate that greater cognitive flexibility and increased activity in the right DLPFC during processing of unexpected negative outcome represents a compensatory resilience mechanism in predisposed twins.

The risk of climate change impacts occurring is a function of a socioecological system’s exposure and vulnerability to climate-related hazards. Vulnerability itself is the result of a system's sensitivity and adaptive capacity. The potential climate change driven biophysical impacts on the municipality Totonicapán in the western highlands of Guatemala are well documented in outcome vulnerability studies and projected to be severe. They include droughts, frosts, forest fires and life zone changes which also represent important hazards to the municipality’s population. Yet, recent detailed socioeconomic information on the municipality’s contextual vulnerability is scarce. Moreover, social capital which is central to the yet successful management of the unique communal coniferous forests is poorly understood. The present study evaluates the contextual vulnerability of the municipality's population and communal forests using 5 interviews and 167 household surveys from 3 communities for 15 socioeconomic indicators. Qualitative analysis of the interviews urges for further investigation into the link between emigration to the USA, the loss of social capital and communal forest management. Quantitative analysis of the indicators and their aggregation into a vulnerability index by Principal Component Analysis demonstrates that education is the most important vulnerability factor, followed by income which was negatively related to natural resource dependency. An overarching theme was gender inequality. The study is a plea for location and population specific research and adaptation strategies as it identifies significant differences even between communities of the same municipality., El riesgo de que ocurran impactos climáticos es la función de la exposición y vulnerabilidad de un sistema socioecológico frente a peligros. La vulnerabilidad es el resultado de la sensibilidad y capacidad adaptativa de un sistema. Los posibles impactos biofísicos debido al cambio climático en el municipio de Totonicapán en el Altiplano de Guatemala son bien documentados en estudios de vulnerabilidad resultante y proyectados a ser severos. Se tratan de sequías, heladas, incendios forestales y cambios en las zonas de vida, que también representan peligros importantes para la población del municipio. Sin embargo, información socioeconómica actualizada y detallada sobre la vulnerabilidad contextual del municipio es escasa. Además, el capital social del municipio que es clave para el manejo exitoso de sus bosques comunales es poco entendido. El presente estudio evalúa la vulnerabilidad contextual de la población del municipio y de los bosques comunales usando 5 entrevistas y 167 encuestas de hogares de 3 comunidades, analizando 15 indicadores socioeconómicos. El análisis cualitativo de las entrevistas resalta que la comprensión del vínculo entre la emigración a los Estados Unidos, la pérdida de capital social y el manejo de los bosques comunales requiere un mayor esfuerzo investigativo. El análisis cuantitativo de los indicadores y su agregación a un índice de vulnerabilidad mediante el Análisis de Componentes Principales demuestra que la educación es el factor más importante de la vulnerabilidad, seguido por el ingreso, que guarda una relación inversa con la dependencia en recursos naturales. Un tema transversal ha sido la desigualdad de género. Identificando diferencias significativas incluso entre comunidades de la misma municipalidad, el estudio es una súplica para investigaciones locales y estrategias de adaptación.

The risk of climate change impacts occurring is a function of a socioecological system’s exposure and vulnerability to climate-related hazards. Vulnerability itself is the result of a system's sensitivity and adaptive capacity. The potential climate change driven biophysical impacts on the municipality Totonicapán in the western highlands of Guatemala are well documented in outcome vulnerability studies and projected to be severe. They include droughts, frosts, forest fires and life zone changes which also represent important hazards to the municipality’s population. Yet, recent detailed socioeconomic information on the municipality’s contextual vulnerability is scarce. Moreover, social capital which is central to the yet successful management of the unique communal coniferous forests is poorly understood. The present study evaluates the contextual vulnerability of the municipality's population and communal forests using 5 interviews and 167 household surveys from 3 communities for 15 socioeconomic indicators. Qualitative analysis of the interviews urges for further investigation into the link between emigration to the USA, the loss of social capital and communal forest management. Quantitative analysis of the indicators and their aggregation into a vulnerability index by Principal Component Analysis demonstrates that education is the most important vulnerability factor, followed by income which was negatively related to natural resource dependency. An overarching theme was gender inequality. The study is a plea for location and population specific research and adaptation strategies as it identifies significant differences even between communities of the same municipality., El riesgo de que ocurran impactos climáticos es la función de la exposición y vulnerabilidad de un sistema socioecológico frente a peligros. La vulnerabilidad es el resultado de la sensibilidad y capacidad adaptativa de un sistema. Los posibles impactos biofísicos debido al cambio climático en el municipio de Totonicapán en el Altiplano de Guatemala son bien documentados en estudios de vulnerabilidad resultante y proyectados a ser severos. Se tratan de sequías, heladas, incendios forestales y cambios en las zonas de vida, que también representan peligros importantes para la población del municipio. Sin embargo, información socioeconómica actualizada y detallada sobre la vulnerabilidad contextual del municipio es escasa. Además, el capital social del municipio que es clave para el manejo exitoso de sus bosques comunales es poco entendido. El presente estudio evalúa la vulnerabilidad contextual de la población del municipio y de los bosques comunales usando 5 entrevistas y 167 encuestas de hogares de 3 comunidades, analizando 15 indicadores socioeconómicos. El análisis cualitativo de las entrevistas resalta que la comprensión del vínculo entre la emigración a los Estados Unidos, la pérdida de capital social y el manejo de los bosques comunales requiere un mayor esfuerzo investigativo. El análisis cuantitativo de los indicadores y su agregación a un índice de vulnerabilidad mediante el Análisis de Componentes Principales demuestra que la educación es el factor más importante de la vulnerabilidad, seguido por el ingreso, que guarda una relación inversa con la dependencia en recursos naturales. Un tema transversal ha sido la desigualdad de género. Identificando diferencias significativas incluso entre comunidades de la misma municipalidad, el estudio es una súplica para investigaciones locales y estrategias de adaptación.