Contributions in Merlin

Sacred values (or protected values) (in German: Geschützte Werte, GW) are values that a community treat as absolute, not tradable and exchangeable for other values. To date, no reliable and valid measure of sacred values has been developed. The research presented here was therefore designed to develop a measure of sacred values (German title: Geschützte Werte Skala, GWS) and to provide preliminary tests. Study 1 examined the reliability and validity of the GWS and revealed satisfactory results. In terms of discriminant validity, the results suggest that GW has to be distinguished from attitude importance. Examining various group differences also supported the validity of the scales. In Study 2, a comparison between two extreme groups (proponents and opponents of gene technology) was conducted. These results provided additional evidence for the validity and conceptual differentiation between GW and attitude importance.

null

Se fondant sur une «analyse d'enveloppement des données» («Data Envelopment Analysis», DEA), le présent article étudie la manière dont a évolué l'efficience des différentes universités suisses de 1999 à 2007 et identifie celles dont la performance a été inférieure aux autres. La plupart des établissements ont bien maîtrisé l'exigeant processus de réforme de la décennie écoulée, malgré quelques difficultés initiales qui ont diminué leur niveau d'efficience. Celui-ci s'est davantage creusé pour les hautes écoles qui ont dû parallèlement mener à bien des restructurations internes et qui ont eu besoin de plus de temps pour parachever leur processus d'adaptation.

Purpose To develop and test a novel method for coil placement in interleaved transcranial magnetic stimulation (TMS)/functional MRI (fMRI) studies.Materials and Methods Initially, a desired TMS coil position at the subject's head is recorded using a neuronavigation system. Subsequently, a custom-made holding device is used for coil placement inside the MR scanner. The parameters of the device corresponding to the prerecorded position are automatically determined from a fast structural image acquired directly before the experiment. The spatial accuracy of our method was verified on a phantom. Finally, in a study on five subjects, the coil was placed above the cortical representation of a hand muscle in M1 and the blood oxygenation level-dependent (BOLD) responses to short repetitive TMS (rTMS) trains were assessed using echo-planar imaging (EPI) recordings.Results The spatial accuracy of our method is in the range of 2.9 ± 1.3 (SD) mm. Motor cortex stimulation resulted in robust BOLD activations in motor- and auditoryrelated brain areas, with the activation in M1 being localized in the hand knob.Conclusion We present a user-friendly method for TMS coil positioning in the MR scanner that exhibits good spatial accuracy and speeds up the setup of the experiment. The motor-cortex study proves the viability of the approach and validates our interleaved TMS/fMRI setup.

Every social group needs to decide when to provide public goods and how to allocate the costs among its members. Ideally, this decision would maximize the group’s net benefits while also ensuring that every individual’s benefit is greater than the cost he or she has to pay. Unfortunately, the economic theory of mechanism design has shown that this ideal solution is not feasible when the group leadership does not know the values of the individual group members for the public good. We show that this impossibility result can be overcome in laboratory settings by combining technologies for obtaining neural measures of value (functional magnetic resonance imaging–based pattern classification) with carefully designed institutions that allocate costs based on both reported and neurally measured values.

A widely observed phenomenon in decision making under risk is the apparent overweighting of unlikely events and the underweighting of nearly certain events. This violates standard assumptions in expected utility theory, which requires that expected utility be linear (objective) in probabilities. Models such as prospect theory have relaxed this assumption and introduced the notion of a “probability weighting function,” which captures the key properties found in experimental data. This study reports functional magnetic resonance imaging (fMRI) data that neural response to expected reward is nonlinear in probabilities. Specifically, we found that activity in the striatum during valuation of monetary gambles are nonlinear in probabilities in the pattern predicted by prospect theory, suggesting that probability distortion is reflected at the level of the reward encoding process. The degree of nonlinearity reflected in individual subjects’ decisions is also correlated with striatal activity across subjects. Our results shed light on the neural mechanisms of reward processing, and have implications for future neuroscientific studies of decision making involving extreme tails of the distribution, where probability weighting provides an explanation for commonly observed behavioral anomalies.

null

null

null