Search

Objectives When motor imagery ( MI) is impaired in stroke patients, it is not clear, whether this is caused by the central lesion with a disruption of networks or this may be due to inactivity/lack of practice following hemiparesis. To answer this question, we investigated MI in two groups of patients: stroke patients and patients with no central lesion, who suffered high-grade tetraparesis caused by myopathy or spinal muscular atrophy. Materials and methods The first study measured MI in 31 sub-acute and chronic stroke patients with hand paresis. We used self-assessment questionnaires [ Kinaesthetic and Visual Imagery Questionnaire ( KVIQ), the Vividness of Motor Imagery Questionnaire ( VMIQ)] as well as a new chronometric test (mental version and normal/physical version of Box and Block Test). The second study assessed MI in 10 patients without a central lesion, but with severe tetraparesis of peripheral origin. They were incapable of performing the requested task physically. Results MI in patients was better (i) for the third-person ( VMIQ3.P) compared to the first-person perspective ( VMIQ1.P), (ii) in patients without sensory impairment compared to those with impaired proprioception, (iii) in patients with light paresis compared to severe paresis and (iv) for the non-affected than the affected hand ( KVIQ-10). Patients with severe tetraparesis were able to imagine another person's knee bends, but were not capable of imagining themselves performing knee bends. Conclusions MI may be hampered on the affected side in severely paretic patients, particularly in the presence of impaired proprioception. Remarkably, the second study illustrates that motor experiences shape MI. This confirms the close relationship between MI and movement execution. The study advocates the careful use of test batteries for assessment of MI when investigating mental training in clinical trials. Not all patients might benefit to the same extent from MI training. This is possibly contingent on intact proprioception and preserved MI. [ABSTRACT FROM AUTHOR]

For more than six years, the automated ultrasonic and eddy current systems for the inspection of railroad wheel sets developed by Fraunhofer IZFP and Fraunhofer TEG have been field-hardened through daily operation at various maintenance facilities of the Deutsche Bahn (DB). The testing stations are equipped with IZFP’s multi-channel electronics, a modular PC integrated system operating inside 19″ rack-mounted industrial computers. Special requirements for new installations of stationary systems (AURA) and underfloor testing stations (UFPE) called for the development of state-of-the-art miniaturised front-end ultrasonic and eddy current test instrumentation. This innovation offers new dimensions for the concept and design of such systems, including features providing effortless maintenance of the inspection systems. Due to the small size of the electronic modules they can be placed in close proximity to the transducer assembly. High-speed networking techniques ensure the transfer of all the acquired digital ultrasonic and eddy current data from the front-end modules to the workstation responsible for data acquisition and analysis. The new front-end technology is applied for the testing stations of the latest generation. One example is a system installed at the DB plant, Krefeld, specifically designed for the ultrasonic testing of Inter-City Express (ICE) train drive wheels. The transducer assembly for wheel rim and disk inspection includes hot-swap modules with integrated UT front-end modules adapted to inspect specific wheel disk configurations. A second example represents testing equipment operating at the Süddeutsche Rail Service GmbH, Kaiserslautern. Ultrasonic and eddy current front-end modules are responsible for the inspection of the wheel rim of disassembled wheel sets of freight cars. In addition to the wheel rim, the solid axle is inspected in the same test stand using GE’s phased array system. Miniaturised front-end modules are also advantageous for the inspection with the wheel sets installed at the train. The concept of such an underfloor testing system is outlined. [ABSTRACT FROM AUTHOR]

Previous standards for the manufacturing inspection of railroad wheels using ultrasound, such as UIC 812, have been replaced by new standards, for example EN 13262 and RD32.144-2000, both requiring ultrasonic testing by means of the immersion technique. These new standards require the development of an ultrasonic technique for 100% coverage of the wheel rim and wheel hub, and in special cases for both straight and curved wheel disks. In order to encompass a large variety of railroad wheel designs, inspection and handling techniques should be capable of dealing with wheel diameters ranging from 600 mm to 1300 mm (23″ to 51″) at testing cycles from 1 to 4 minutes per wheel. The current requirement for the minimum detectable flaw size is DSR 1 mm (disc shape reflector, DSR, 1 mm diameter) for high-speed train wheels rims and DSR 2 mm for all other wheel rims. The minimum detectable flaw size for all other wheel areas (hub and disk areas) is DSR 3 mm. To meet all these criteria, a Rail Wheel Inspection (RWI) system was developed by IZFP and its partners. The system consists of an ultrasonic testing sub-system, immersion tank and transportation/handling sub-systems. Test cycles of 1 minute per wheel require two immersion tanks and two transportation/handling sub-systems. The ultrasonic sub-system features modular computer-aided 6 to 16-channel UT electronics (PCUS 11) to employ 6 to 16 ultrasonic transducers (the precise number is determined by the testing procedure). This paper offers descriptions of, and results from, three of these systems that have been integrated into manufacturing processes at German and Russian wheel manufacturers, and provides details on the following topics: □ Wheel rim inspection, single-tank immersion technique, 4 minute inspection cycle per wheel (Bochum, Germany) □ Wheel rim, hub and disc inspection, single-tank immersion technique, 2 minute inspection cycle per wheel (Ilsenburg, Germany) □ Wheel rim, hub and disc inspection, dual-tank immersion technique, 1 minute inspection cycle per wheel (Nishny-Tagil, Russia) [ABSTRACT FROM AUTHOR]

Psychotherapie verändert klinische Symptome und mentale Funktionen und damit auch Leistungen des Gehirns. Dies bedeutet, dass sich die Architektur des Gehirns durch erfolgreiche therapeutische Intervention modifizieren lässt. Tatsächlich kann der Nachweis sogar auf makroskopischer Ebene gelingen, wie wir hier am Beispiel der Behandlung seelischer Erkrankungen in Folge von traumatischem Stress darlegen. Die Narrative Expositionstherapie (NET) wurde dabei mit Standardbehandlungen (TU; treatment as usual) bei traumatisierten Asylsuchenden in Deutschland verglichen. Der Erfolg der NET spiegelte sich nicht nur in den Symptomkennwerten wider, sondern auch in neuromagnetischen Messungen. Diese zeigten in der 6-Monats-Katamnese, dass sich die Hirnaktivität in der NET-Gruppe an diejenige einer psychisch unauffälligen Normstichprobe angenähert hatte. In der TU-Gruppe war dies nicht der Fall. Neurophysiologische Messungen können somit (1) den Therapieerfolg validieren, (2) Wirkmechanismen einer Therapieform berprüfen, wodurch ein Zugang zu besserer Modellierung geschaffen wird, (3) die differentialdiagnostischen Möglichkeiten erweitern und (4) uns einmal mehr lehren, dass Geist und Gehirn lediglich zwei Informationsebenen ein und desselben Phänomens darstellen. [ABSTRACT FROM AUTHOR]

Slow cortical potentials, response speed, and peripheral physiological responses were investigated in two experiments with four groups of male subjects. Experiment 1 examined constant foreperiod reaction time in a sound light button press sequence with an interstimulus interval of 2 sec. Experiment 2 investigated constant foreperiod reaction time conditions with a sudden change from controllable to uncontrollable offset of an aversive imperative stimulus. There were two visual warning stimuli of 6-sec duration followed by an aversive or neutral imperative stimulus to be terminated by button press within I sec. Forty trials of this contingency were followed by 40 trials with 5-sec duration of imperative stimuli irrespective of response speed. Subjects were selected by high or low scores on two questionnaire scales measuring physical anhedonia (PA) and body image distortion (BI). In the first paradigm subjects with high PA scores as compared to low-scoring subjects showed less resolution of left precentral CNV after S2, i.e., a more pronounced post-imperative negative component. In the second paradigm a postimperative negative variation (PINV) developed in all groups, but was more pronounced in frontal recordings and in subjects with high PA and BI scores. Results are discussed in the context of electrocortical phenomena observed in psychopathological groups. [ABSTRACT FROM AUTHOR]

The study aimed to explore the predictive value of neuropsychological tests within the context of acquisition of slow cortical potential (SCP) self-control, a technique which has beneficial effects on seizure frequency in epilepsy. Patients with epilepsy who successfully achieved SCP control had longer digit or block-tapping spans than less successful patients. Patients who showed a better learning rate across training also displayed better verbal memory and learning abilities. Seizure reduction was related to block-tapping spans only. The results indicate that measures of attention, as indicated by digit spans or block-tapping spans, offer some predictive value for acquisition of SCP control and treatment outcome, whilst measures of visuospatial or frontal lobe function are unrelated to SCP acquisition and seizure reduction. [ABSTRACT FROM AUTHOR]