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Gilching, Germany

Brummer V.,German Sport University Cologne | Schneider S.,German Sport University Cologne | Vogt T.,German Sport University Cologne | Struder H.,German Sport University Cologne | And 3 more authors.
Journal of Visualized Experiments | Year: 2011

Previous studies of cognitive, mental and/or motor processes during short-, medium- and long-term weightlessness have only been descriptive in nature, and focused on psychological aspects. Until now, objective observation of neurophysiological parameters has not been carried out - undoubtedly because the technical and methodological means have not been available -, investigations into the neurophysiological effects of weightlessness are in their infancy (Schneider et al. 2008). While imaging techniques such as positron emission tomography (PET) and magnetic resonance imaging (MRI) would be hardly applicable in space, the non-invasive near-infrared spectroscopy (NIRS) technique represents a method of mapping hemodynamic processes in the brain in real time that is both relatively inexpensive and that can be employed even under extreme conditions. The combination with electroencephalography (EEG) opens up the possibility of following the electrocortical processes under changing gravity conditions with a finer temporal resolution as well as with deeper localization, for instance with electrotomography (LORETA). Previous studies showed an increase of beta frequency activity under normal gravity conditions and a decrease under weightlessness conditions during a parabolic flight (Schneider et al. 2008a+b). Tilt studies revealed different changes in brain function, which let suggest, that changes in parabolic flight might reflect emotional processes rather than hemodynamic changes. However, it is still unclear whether these are effects of changed gravity or hemodynamic changes within the brain. Combining EEG/LORETA and NIRS should for the first time make it possible to map the effect of weightlessness and reduced gravity on both hemodynamic and electrophysiological processes in the brain. Initially, this is to be done as part of a feasibility study during a parabolic flight. Afterwards, it is also planned to use both techniques during medium- and long-term space flight. It can be assumed that the long-term redistribution of the blood volume and the associated increase in the supply of oxygen to the brain will lead to changes in the central nervous system that are also responsible for anaemic processes, and which can in turn reduce performance (De Santo et al. 2005), which means that they could be crucial for the success and safety of a mission (Genik et al. 2005, Ellis 2000). Depending on these results, it will be necessary to develop and employ extensive countermeasures. Initial results for the MARS500 study suggest that, in addition to their significance in the context of the cardiovascular and locomotor systems, sport and physical activity can play a part in improving neurocognitive parameters. Before this can be fully established, however, it seems necessary to learn more about the influence of changing gravity conditions on neurophysiological processes and associated neurocognitive impairment. © 2011 Journal of Visualized Experiments. Source

Prunescu M.,Brain Products GmbH | Prunescu M.,Romanian Academy Research Unit 5
Symmetry | Year: 2011

The author used the automatic proof procedure introduced in [1] and verified that the 4096 homomorphic recurrent double sequences with constant borders defined over Klein's Vierergruppe K{double-struck} and the 4096 linear recurrent double sequences with constant border defined over the matrix ring M 2F{double-struck}( 2) can be also produced by systems of substitutions with finitely many rules. This permits the definition of a sound notion of geometric content for most of these sequences, more exactly for those which are not primitive. We group the 4096 many linear recurrent double sequences with constant border I over the ring M 2F{double-struck}( 2) in 90 geometric types. The classification over Klein's Vierergruppe K is not explicitly displayed and consists of the same geometric types like for M 2F{double-struck}( 2), but contains more exceptions. There are a lot of cases of unsymmetric double sequences converging to symmetric geometric contents. We display also geometric types occurring both in a monochromatic and in a dichromatic version. © 2011 by the author. Source

Noth U.,Goethe University Frankfurt | Laufs H.,Goethe University Frankfurt | Stoermer R.,Brain Products GmbH | Deichmann R.,Goethe University Frankfurt
Journal of Magnetic Resonance Imaging | Year: 2012

Purpose: To describe heating effects to be expected in simultaneous electroencephalography (EEG) and magnetic resonance imaging (MRI) when deviating from the EEG manufacturer's instructions; to test which anatomical MRI sequences have a sufficiently low specific absorption rate (SAR) to be performed with the EEG equipment in place; and to suggest precautions to reduce the risk of heating. Materials and Methods: Heating was determined in vivo below eight EEG electrodes, using both head and body coil transmission and sequences covering the whole range of SAR values. Results: Head transmit coil: temperature increases were below 2.2°C for low SAR sequences, but reached 4.6°C (one subject, clavicle) for high SAR sequences; the equilibrium temperature T eq remained below 39°C. Body transmit coil: temperature increases were higher and more frequent over subjects and electrodes, with values below 2.6°C for low SAR sequences, reaching 6.9°C for high SAR sequences (T8 electrode) with T eq exceeding a critical level of 40°C. Conclusion: Anatomical imaging should be based on T1-weighted sequences (FLASH, MPRAGE, MDEFT) with an SAR below values for functional MRI sequences based on gradient echo planar imaging. Anatomical sequences with a high SAR can pose a significant risk, which is reduced by using head coil transmission. Copyright © 2011 Wiley-Liss, Inc. Source

Agency: Cordis | Branch: FP7 | Program: MC-ITN | Phase: FP7-PEOPLE-2011-ITN | Award Amount: 3.03M | Year: 2012

The ACT Initial Training Network aims to establish a leading European training network devoted to investigating the interplay between action and cognition using a developmental approach. The ACT network represents a collective of scientific and industrial groups at the cutting edge of research in the fields of social development, developmental psychology, cognitive science, developmental neuropsychology, and computational science. The network will train PhD students and produce new technology to answer critical issues in our understanding of human development. A core assumption of the network is that development of perception, motivation, and cognition is grounded in, and develops through, our own actions (von Hofsten, 2004). We learn about our physical environment by actively engaging with the world. As we develop new action capabilities, new elements of the environment become salient to us. This process is especially prominent early in infancy when action capacities and an understanding of the world develop. The nature of developmental research demands a multi-method approach. As a result, we propose to rigorously train ESRs such that they obtain two or more techniques required to study the relationship between brain and behaviour in early social development. We will conduct research and training within and between academic and industry partners on the role of attention in action, prospective control, social interactions, and semantics in action. We will improve technologies so that movement analysis is possible with infants. We will also develop an eye tracking system that links to EEG and we will create tools that are designed specifically for infant EEG data. In addition to these major breakthroughs in our knowledge, we will provide a structured training programme for Early Stage Researchers that capitalizes on cross-European strengths that will produce cutting edge leaders within the field in a unique and timely interdisciplinary training programme.

An electrode for detecting EEG signals comprises a body comprising a fixture on a first end of the body, and a sensor detachably held by the fixture, wherein the body has an external thread in a portion of the body extending from the first end of the body towards a second end of the body, and the sensor has a brush-like shape with pins protruding off the body. The electrode may be held by an attaching device for holding electrodes for detecting EEG signals, the attaching device comprising a strap including a plurality of holes for accommodating electrodes and a rotary closure connecting a first end of the strap and a second end of the strap.

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