Brain tissues have single-voxel signatures in multi-spectral MRI

We acquired diffusion-weighted and CEST data of the brain of 38 healthy volunteers. A MPRAGE and SWI based segmentation into 102 brain regions revealed unique diffusion and chemical MR signals on average. More importantly, we could infer these tissue classes form individual voxel data using a neural network. The revival of this old paradigm for tissue characterization from the 1990s points to the fact that unique MR signals of different brain regions exist and can be used to determine the tissue type voxel-wise. The approach as such is general and could unify the ever-growing diversity of MR contrasts

Hirngewebe besitzen Einzel-Voxel-Signaturen in multispektraler MR Bildgebung

Seit den Arbeiten von Brodmann und seinen Zeitgenossen ist bekannt, dass verschiedene Hirnregionen aufgrund ihrer ein-zigartigen zyto- und myeloarchitektonischen Merkmale unterscheidbar und klassifizierbar sind. Hier habe ich in Kooperation mit einem interdisziplinären Team die Machbarkeit der Übertragung dieses klassischen Klassifizie-rungsansatz auf die MRT untersucht und dabei mehrere technologische Fortschritte genutzt: Ultrahochfeld-MRT, q-Raum-Trajektorienbild gebung, chemische Austausch-Sättigungs-MRT, sowie aktuelle neuronale Netzwerkarchi-tekturen. Es zeigte sich, dass eine globale Hirnklassifikation von 97 Hirnregionen mit einer Klassifikationsgenauigkeit von 60% möglich ist

Support for real-time decision making in mobile financial applications

Mobile users making real-time decisions based on current information need confidence about their context been taken into consideration in producing recommendations. This chapter reviews current use of mobile technologies for decision support. Specifically, it describes a framework for assessing the impact of mobility in decision-making. The framework uses dynamic context representation of data quality to represent uncertainties in the mobile computing environment. This framework can be used for developing visual interactive displays for communicating to the user relevant changes in data quality when working in mobile environment. As an illustration, this chapter proposes a real-time decision support procedure that aims at providing on-the-spot assistance to the mobile consumer when choosing the best payment option to efficiently manage the user’s budget. The proposed procedure is based on multi-attribute decision analysis, scenario reasoning and a quality of data framework. Feasibility of the approach is demonstrated with a mobile decision support system prototype implementation

The Ecological Rationality of Simple Group Heuristics: Effects of Group Member Strategies on Decision Accuracy

The notion of ecological rationality implies that the accuracy of a decision strategy depends on features of the information environment in which it is tested. We demonstrate that the performance of a group may be strongly affected by the decision strategies used by its individual members and specify how this effect is moderated by environmental features. Specifically, in a set of simulation studies, we systematically compared four decision strategies used by the individual group members: two linear, compensatory decision strategies and two simple, noncompensatory heuristics. Individual decisions were aggregated by using a majority rule. To assess the ecological rationality of the strategies, we varied (a) the distribution of cue validities, (b) the quantity, and (c) the quality of shared information. Group performance strongly depended on the distribution of cue validities. When validities were linearly distributed, groups using a compensatory strategy achieved the highest accuracy. Conversely, when cue validities followed a J-shaped distribution, groups using a simple lexicographic heuristic performed best. While these effects were robust across different quantities of shared information, the quality of shared information exerted stronger effects on group performance. Consequences for prescriptive theories on group decision making are discussed Copyright Springer 2006compensatory and noncompensatory decision strategies, group decision making, group performance, simple heuristics,