The dependence of the neuromagnetic source localization accuracy on the volume conductor model was studied by the analysis of measured magnetic fields generated by tangentially oriented dipoles in a ...realistically shaped skull phantom. When using a homogeneous sphere model in the localization procedure, the errors were found to increase from about 3 mm to about 9 mm when the distance between the dipoles and the inner surface of the skull increased from 1 cm to 3 cm, whereas when using a true, realistic model in the inverse procedure the localization errors were only about 2-3 mm, independent of dipole depth. To account for the realistic geometry of the inner surface of the skull, the Boundary Element Method, based on a surface discretization in terms of about 300 triangles, proved to be sufficient. In addition to these analyses of experimental data, simulations were carried out to study the localization errors in the case of the spherical approximation for a dipole orientation changing from tangential to radial. For the latter orientation, errors of up to a few centimeters were found.< >
Sources of the somatosensory evoked fields (SEF) for one subject were estimated using constraints from the magnetic resonance images (MRI) of the same subject. A realistic volume conductor model was ...shaped corresponding to the inside of the skull. Sources were restricted to a dipole patch riding on the surface of the cortex, reconstructed from the individual MRI. Such a patch can be considered as a uniformly activated cortical area giving rise to distributed currents which flow perpendicular to the cortical surface. Source locations obtained for the SEF in response to separate stimulations of lower lip, first and fifth digit, and collarbone followed the course of the contralateral central sulcus. The order of the estimated source locations was in agreement with the somatosensory homunculus of Penfield and Rasmussen. Similar results were obtained with the simple model of a current dipole in a homogeneous sphere. In contrast, combining a current dipole model with a realistic volume conductor model was rather problematic as it overestimates the radial dipole component by an order of magnitude.
Computer-aided collaborative and multi-scale 3D planning are challenges for complex railway and subway track infrastructure projects in the built environment. Many legal, economic, environmental, and ...structural requirements have to be taken into account. The stringent use of 3D models in the different phases of the planning process facilitates communication and collaboration between the stake holders such as civil engineers, geological engineers, and decision makers. This paper presents concepts, developments, and experiences gained by an interdisciplinary research group coming from civil engineering informatics and geo-informatics banding together skills of both, the Building Information Modeling and the 3D GIS world. New approaches including the development of a collaborative platform and 3D multi-scale modelling are proposed for collaborative planning and simulation to improve the digital 3D planning of subway tracks and other infrastructures. Experiences during this research and lessons learned are presented as well as an outlook on future research focusing on Building Information Modeling and 3D GIS applications for cities of the future.
Metrical patterning and rhyme are frequently employed in poetry but also in infant-directed speech, play, rites, and festive events. Drawing on four line-stanzas from nineteenth and twentieth German ...poetry that feature end rhyme and regular meter, the present study tested the hypothesis that meter and rhyme have an impact on aesthetic liking, emotional involvement, and affective valence attributions. Hypotheses that postulate such effects have been advocated ever since ancient rhetoric and poetics, yet they have barely been empirically tested. More recently, in the field of cognitive poetics, these traditional assumptions have been readopted into a general cognitive framework. In the present experiment, we tested the influence of meter and rhyme as well as their interaction with lexicality in the aesthetic and emotional perception of poetry. Participants listened to stanzas that were systematically modified with regard to meter and rhyme and rated them. Both rhyme and regular meter led to enhanced aesthetic appreciation, higher intensity in processing, and more positively perceived and felt emotions, with the latter finding being mediated by lexicality. Together these findings clearly show that both features significantly contribute to the aesthetic and emotional perception of poetry and thus confirm assumptions about their impact put forward by cognitive poetics. The present results are explained within the theoretical framework of cognitive fluency, which links structural features of poetry with aesthetic and emotional appraisal.
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