Das Ausmaß von Müdigkeit und Erschöpfbarkeit in der über 60-jährigen Normalbevölkerung in Deutschland

In a community-based random sample of 622 elderly persons over 60 years of age, fatigue was assessed by means of the multidimensional fatigue inventory (MFI; a self-assessment measure). Higher fatigue values were found with increasing age, particularly physical feelings of fatigue, reduced activity and reduced motivation. Fatigue was associated with depression, with a low health-related quality of life and with subjective physical complaints. Distinct fatigue symptoms in the elderly should therefore be regarded as possible indicators for somatic and/or psychological burdens and should receive diagnostic and therapeutic attention. In the present paper, mean values and percentiles for different age groups over 60 years are given as norm values for the normal population over 60 years of age.     

Mental object rotation and the planning of hand movements

Recently, we showed that the simultaneous execution of rotational hand movements interferes with mental object rotation, provided that the axes of rotation coincide in space. We hypothesized that mental object rotation and the programming of rotational hand movements share a common process presumably involved in action planning. Two experiments are reported here that show that the mere planning of a rotational hand movement is sufficient to cause interference with mental object rotation. Subjects had to plan different spatially directed hand movements that they were asked to execute only after they had solved a mental object rotation task. Experiment 1 showed that mental object rotation was slower if hand movements were planned in a direction opposite to the presumed mental rotation direction, but only if the axes of hand rotation and mental object rotation were parallel in space. Experiment 2 showed that this interference occurred independent of the preparatory hand movements observed in Experiment 1. Thus, it is the planning of hand movements and not their preparation or execution that interferes with mental object rotation. This finding underlines the idea that mental object rotation is an imagined (covert) action, rather than a pure visual-spatial imagery task, and that the interference between mental object rotation and rotational hand movements is an interference between goals of actions.     

B. Gordijn/H. ten Have (eds), ``Medizinethik und Kultur. Grenzen medizinischen Handelns in Deutschland und den Niederlanden'

Theoretical Medicine and Bioethics -     

Weshalb implizite definitionen nicht genug sind. Bedeutungstheorien und das verst?ndnis physikalischer begriffe

Ohne Zusammenfassung     

Application of the Bower and Trabasso theory to four-category concept learning with probabilistic feedback

Four-category conjunctive concept problems were learned under nine different conditions with the number of irrelevant dimensions and the percentage of correct feedback as independent variables. Concept identification performance could be adequately predicted by assuming that the two relevant dimensions defining the conjunctive problems were learned concurrently and independently. A generalized version of the Bower-Trabasso theory of concept identification, encompassing a distinct response learning phase, was applied to the data. The theory adequately described performance under conditions with consistently correct feedback. Several alternative models for learning under misinformative feedback conditions were developed from the theory. Using parameter estimates from data under correct feedback conditions, these models were found to predict performance under misinformative feedback fairly well.