The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

Party and Candidate Websites: A Comparative Explanatory Analysis

This study provides a systematic investigation of party and candidate websites across five countries. It examines three prominent features of current online political communication (interactivity, political personalization, and mobilization). Furthermore it assesses to what extent country, party, and source characteristics explain differences in the usage of these features. In total, 63 websites and 416 pages in Germany, Romania, Hungary, the Netherlands, and Great Britain were subject to a systematic content analysis. The findings suggest that differences in party and source characteristics explain variation in levels of mobilization, interactivity, and personalization, with, for example, party websites trying to mobilize citizens while websites belonging to politicians are used as a platform for self-promotion. In general, results show that the division of countries into East and West European is less important