Kognitive Verarbeitung wertbasierter Entscheidungen bei Führungskräften - eine neuropsychoökonomische Studie

Die vorliegende Arbeit beschäftigt sich mit möglichen neurobiologischen Korrelaten wertbasierter Entscheidungen bei Führungskräften. Eine breite Theoriebasis zu Führungs- und Entscheidungsverhalten in Verbindung mit den Wertemustern einer Person deutete auf unterschiedliche kognitive Verarbeitungsmuster von Führungskräften im Vergleich zu Nicht-Führungskräften hin. In einem interdisziplinären Ansatz wurden in dieser Arbeit erstmals spezifische betriebswirtschaftliche Fragestellungen der Führungsforschung mit neurowissenschaftlichen Methoden untersucht. In einem ersten Experiment wurden mit Hilfe der funktionellen Magnetresonanztomographie (fMRT) mögliche unterschiedliche neurobiologische Korrelate wertbasierter Entscheidungen in Abhängigkeit vom dominierenden Wertemuster einer Person untersucht. Es zeigte sich, dass zwei Komponenten wertbasierter Verarbeitung in Abhängigkeit vom dominierenden Werteprofil einer Person unterschiedlich rekrutiert wurden: Personen mit überwiegend individualistischem Wertemuster zeigten eine stärkere Aktivierung der emotionalen Verarbeitungskomponente (Aktivierung in der Amygdala, dem Mandelkern des Gehirns), während kollektivistisch geprägte Personen eher Hirnregionen der rationalen Verarbeitungskomponente nutzten (Stirn- und Scheitellappen). In einem zweiten Experiment wurde das gleiche Experiment zu wertbasierter Entscheidungsfindung von Führungskräften und Nicht-Führungskräften durchgeführt, bei dem die Führungskräfte ganz überwiegend individualistische Wertemuster zeigten. Bei diesen Personen konnten Unterschiede in der kognitiven Verarbeitungsstrategie im Vergleich zu individualistischen Nicht-Führungskräften gefunden werden: Während die Nicht-Führungskräfte eine stärkere Aktivierung in verschiedenen Hirnrindenregionen zur Aufnahme und Verarbeitung der dargebotenen Stimuli und rationalen Entscheidungsfindung zeigten, dominierte bei den Führungskräften eine Aktivierung im Bereich der Stammganglien (Kopf des Nucleus caudatus (Schweifkern)), die mit kategoriellem Lernen und schnellem Online-Updating von Informationen zur Entscheidungsfindung in Verbindung gebracht wurde. Diese Ergebnisse deuteten somit darauf hin, dass Führungskräfte eine andere Art von Verarbeitung in einer einfachen, repetitiven Entscheidungssituation, wie sie im vorliegenden Paradigma verwendet wurde, nutzten als Nicht-Führungskräfte. Somit konnten neurowissenschaftliche Hinweise für die empirisch ermittelten und theoretisch vermuteten Unterschiede im Entscheidungsverhalten zwischen Führungskräften und Nicht-Führungskräften ermittelt werden

Notes on fiber length measurements : a case study in the underbelly of open source neuroscience

Being on the bleeding edge of research requires the use of new and regularly updated software. The result is the occasional and inevitable occurrence of bugs. In the following work we present a case study where a feature request introduced a bug in a neuroimaging software package, which had consequences for the quality of results in a published article. We discuss the process of diagnosis, rectification and analysis replication.peer-reviewe

The influence of bilingualism on gray matter volume in the course of aging: a longitudinal study

BackgroundBilingualism is associated with higher gray matter volume (GMV) as a form of brain reserve in brain regions such as the inferior frontal gyrus (IFG) and the inferior parietal lobule (IPL). A recent cross-sectional study reported the age-related GMV decline in the left IFG and IPL to be steeper for bilinguals than for monolinguals. The present study aimed at supporting this finding for the first time with longitudinal data.MethodsIn the current study, 200 participants aged 19 to 79 years (87 monolinguals, 113 sequential bilinguals, mostly native German speakers with variable second language background) were included. Trajectories of GMV decline in the bilateral IFG and IPL were analyzed in mono- and bilinguals over two time points (mean time interval: 3.6 years). For four regions of interest (left/right IFG and left/right IPL), mixed Analyses of Covariance were conducted to assess (i) GMV changes over time, (ii) GMV differences for language groups (monolinguals/bilinguals), and (iii) the interaction between time point and language group. Corresponding analyses were conducted for the two factors of GMV, surface area (SA) and cortical thickness (CT).ResultsThere was higher GMV in bilinguals compared to monolinguals in the IPL, but not IFG. While the left and right IFG and the right IPL displayed a similar GMV change in mono- and bilinguals, GMV decline within the left IPL was significantly steeper in bilinguals. There was greater SA in bilinguals in the bilateral IPL and a steeper CT decline in bilinguals within in the left IPL.ConclusionThe cross-sectional observations of a steeper GMV decline in bilinguals could be confirmed for the left IPL. Additionally, the higher GMV in bilinguals in the bilateral IPL may indicate that bilingualism contributes to brain reserve especially in posterior brain regions. SA appeared to contribute to bilinguals’ higher GMV in the bilateral IPL, while CT seemed to account for the steeper structural decline in bilinguals in the left IPL. The present findings demonstrate the importance of time as an additional factor when assessing the neuroprotective effects of bilingualism on structural features of the human brain

The role of thickness inhomogeneities in hierarchical cortical folding

For long it has been known that specific patterns of folding are necessary for an optimally functioning brain. For instance, lissencephaly and polymicrogyria can lead to severe mental retardation, short life expectancy, epileptic seizures, and tetraplegia. The construction of a quantitative model on how and why these folds appear is the first step in understanding the cause of these conditions. In recent years, there have been various attempts to understand and model the mechanisms of brain folding. Previous works have shown that mechanical instabilities play a crucial role in the formation of brain folds, and that the geometry of the fetal brain is one of the main factors in dictating the folding characteristics. However, modeling higher-order folding, one of the main characteristics of the human brain, has not been fully tackled. The effects of thickness inhomogeneity in the gyrogenesis of the mammalian brain are studied through finite-element simulations of rectangular slabs. The slabs are divided into two distinct regions, where the outer layer mimics the gray matter, and the inner layer the underlying white matter. Differential growth is introduced by only growing the top layer. The brain tissue is modeled as a neo-Hookean hyperelastic material. Simulations are performed with both, homogeneous and inhomogeneous cortical thickness. The homogeneous cortex is shown to fold into a single wavelength, as common for bilayered materials, while the inhomogeneous cortex folds into more complex conformations: In their early stages of development, structures reminiscent of the deep sulci in the brain are obtained. As the cortex continues to develop, secondary undulations, which are shallower and more variable than the structures obtained in earlier gyrification stage emerge, reproducing well-known characteristics of higher-order folding in the mammalian, and particularly the human, brain.Comment: 13 pages,10 figure

Cytoarchitectonic mapping of the human frontal operculum—New correlates for a variety of brain functions

The human frontal operculum (FOp) is a brain region that covers parts of the ventral frontal cortex next to the insula. Functional imaging studies showed activations in this region in tasks related to language, somatosensory, and cognitive functions. While the precise cytoarchitectonic areas that correlate to these processes have not yet been revealed, earlier receptorarchitectonic analysis resulted in a detailed parcellation of the FOp. We complemented this analysis by a cytoarchitectonic study of a sample of ten postmortem brains and mapped the posterior FOp in serial, cell-body stained histological sections using image analysis and multivariate statistics. Three new areas were identified: Op5 represents the most posterior area, followed by Op6 and the most anterior region Op7. Areas Op5-Op7 approach the insula, up to the circular sulcus. Area 44 of Broca’s region, the most ventral part of premotor area 6, and parts of the parietal operculum are dorso-laterally adjacent to Op5-Op7. The areas did not show any interhemispheric or sex differences. Three-dimensional probability maps and a maximum probability map were generated in stereotaxic space, and then used, in a first proof-of-concept-study, for functional decoding and analysis of structural and functional connectivity. Functional decoding revealed different profiles of cytoarchitectonically identified Op5-Op7. While left Op6 was active in music cognition, right Op5 was involved in chewing/swallowing and sexual processing. Both areas showed activation during the exercise of isometric force in muscles. An involvement in the coordination of flexion/extension could be shown for the right Op6. Meta-analytic connectivity modeling revealed various functional connections of the FOp areas within motor and somatosensory networks, with the most evident connection with the music/language network for Op6 left. The new cytoarchitectonic maps are part of Julich-Brain, and publicly available to serve as a basis for future analyses of structural-functional relationships in this region

Occipital Intralobar fasciculi : a description, through tractography, of three forgotten tracts

Diffusion MRI paired with tractography has facilitated a non-invasive exploration of manyassociation, projection, and commissuralfiber tracts. However, there is still a scarcity ofresearch studies related to intralobar associationfibers. The Dejerines’(two of the mostnotable neurologists of 19thcentury France) gave an in-depth description of the intralobarfibers of the occipital lobe. Unfortunately, their exquisite work has since been sparsely citedin the modern literature. This work gives a modern description of many of the occipitalintralobar lobefibers described by the Dejerines. We perform a virtual dissection andreconstruct the tracts using diffusion MRI tractography. The dissection is guided by theDejerines’treatise,Anatomie des Centres Nerveux. As an accompaniment to this article, weprovided a French-to-English translation of the treatise portion concerningfive intra-occipitaltracts, namely: the stratum calcarinum, the stratum proprium cunei, the vertical occipitalfasciculus of Wernicke, the transverse fasciculus of the cuneus and the transverse fasciculusof the lingual lobule of Vialet. It was possible to reconstruct all but one of these tracts.For completeness, the recently described sledge runner fasciculus, although not one of theDejerines’tracts, was identified and successfully reconstructed.peer-reviewe

Исследование технологических возможностей термической правки нежестких деталей из алюминиевого сплава АМГ6

В работе проведено экспериментальное исследование по поиску оптимальных режимов термоправки нежёсткой детали из алюминиевого сплава АМг6. Исследовано внутреннее напряженное состояние заготовок. Работа направлена на улучшение существующих технологий производства нежестких деталей.In this work, an experimental study was carried out to find the optimal modes of thermal correction for a non-rigid part made of an aluminum alloy AM6. The internal stress state of the blanks was studied. The work is aimed at improving existing production technologies for non-rigid parts

Sharing brain imaging data in the Open Science era:how and why?

The sharing of human neuroimaging data has great potential to accelerate the development of imaging biomarkers in neurological and psychiatric disorders; however, major obstacles remain in terms of how and why to share data in the Open Science context. In this Health Policy by the European Cluster for Imaging Biomarkers, we outline the current main opportunities and challenges based on the results of an online survey disseminated among senior scientists in the field. Although the scientific community fully recognises the importance of data sharing, technical, legal, and motivational aspects often prevent active adoption. Therefore, we provide practical advice on how to overcome the technical barriers. We also call for a harmonised application of the General Data Protection Regulation across EU countries. Finally, we suggest the development of a system that makes data count by recognising the generation and sharing of data as a highly valuable contribution to the community.</p

Age-Related Changes of Peak Width Skeletonized Mean Diffusivity (PSMD) Across the Adult Lifespan: A Multi-Cohort Study

Parameters of water diffusion in white matter derived from diffusion-weighted imaging (DWI), such as fractional anisotropy (FA), mean, axial, and radial diffusivity (MD, AD, and RD), and more recently, peak width of skeletonized mean diffusivity (PSMD), have been proposed as potential markers of normal and pathological brain ageing. However, their relative evolution over the entire adult lifespan in healthy individuals remains partly unknown during early and late adulthood, and particularly for the PSMD index. Here, we gathered and analyzed cross-sectional diffusion tensor imaging (DTI) data from 10 population-based cohort studies in order to establish the time course of white matter water diffusion phenotypes from post-adolescence to late adulthood. DTI data were obtained from a total of 20,005 individuals aged 18.1 to 92.6 years and analyzed with the same pipeline for computing skeletonized DTI metrics from DTI maps. For each individual, MD, AD, RD, and FA mean values were computed over their FA volume skeleton, PSMD being calculated as the 90% peak width of the MD values distribution across the FA skeleton. Mean values of each DTI metric were found to strongly vary across cohorts, most likely due to major differences in DWI acquisition protocols as well as pre-processing and DTI model fitting. However, age effects on each DTI metric were found to be highly consistent across cohorts. RD, MD, and AD variations with age exhibited the same U-shape pattern, first slowly decreasing during post-adolescence until the age of 30, 40, and 50 years, respectively, then progressively increasing until late life. FA showed a reverse profile, initially increasing then continuously decreasing, slowly until the 70s, then sharply declining thereafter. By contrast, PSMD constantly increased, first slowly until the 60s, then more sharply. These results demonstrate that, in the general population, age affects PSMD in a manner different from that of other DTI metrics. The constant increase in PSMD throughout the entire adult life, including during post-adolescence, indicates that PSMD could be an early marker of the ageing process