Publications by authors named "Steiger T"

Neural degeneration is a hallmark of healthy aging and can be associated with specific cognitive impairments. However, neural degeneration per se is not matched by unremitting declines in cognitive abilities. Instead, middle-aged and older adults typically maintain surprisingly high levels of cognitive functioning, suggesting that the human brain can adapt to structural degeneration by neural compensation.

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Novelty can promote subsequent long-term memory via the mesolimbic system, including the medial temporal lobe and midbrain structures. Importantly, these and other brain regions typically degenerate during healthy aging, which suggests a reduced impact of novelty on learning. However, evidence in favor of such a hypothesis is scarce.

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Our ability to rapidly distinguish new from already stored (old) information is important for behavior and decision making, but the underlying processes remain unclear. Here, we tested the hypothesis that contextual cues lead to a preselection of information and, therefore, faster recognition. Specifically, on the basis of previous modeling work, we hypothesized that recognition time depends on the amount of relevant content stored in long-term memory, i.

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Novelty anticipation activates the mesolimbic system and promotes subsequent long-term memory in younger adults. Importantly, mesolimbic structures typically degenerate with age, which might reduce positive effects of novelty anticipation. Here, we used electroencephalography in combination with an established paradigm in healthy young (19-33 years old, n = 28) and older (53-84, n = 27) humans.

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Learning novel information can be promoted if it is congruent with already stored knowledge. This so-called semantic congruence effect has been broadly studied in healthy young adults with a focus on neural encoding mechanisms. However, the impacts on retrieval, and possible impairments during healthy aging, which is typically associated with changes in declarative long-term memory, remain unclear.

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Age-related cognitive decline has been linked to alterations of the dopaminergic system and its subcortical trajectories. Recent work suggests a critical role of iron accumulation within the basal ganglia (BG) in verbal memory performance, and increased iron levels have been related to demyelination. However, the specificity of age-related iron increases with respect to cognitive functions remains unclear.

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Objective: Failure of membrane oxygenator (MO) function of venovenous extracorporeal membrane oxygenators (VV ECMO) remains problematic. The development of device-induced coagulation disorder (COD) or worsened gas transfer (WGT) necessitates a system exchange. The aim was to correlate von Willebrand factor antigen (vWF:Ag) with the predisposition to MO failure and mortality.

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Long-term memory can improve when incoming information is congruent with known semantic information. This so-called congruence effect has widely been shown in younger adults, but age-related changes and neural mechanisms remain unclear. Here, congruence improved recognition memory in younger and older adults (i.

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Cognitive training should not only improve performance of the trained task, but also untrained abilities. Exposure to novelty can improve subsequent memory performance, suggesting that novelty exposure might be a critical factor to promote the effects of cognitive training. Therefore, we combined a 4-week working memory training with novelty exposure.

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Clot formation within membrane oxygenators (MOs) remains a critical problem during extracorporeal membrane oxygenation (ECMO). The composition of the clots-in particular, the presence of von Willebrand factor (vWF)-may be an indicator for prevalent nonphysiological flow conditions, foreign body reactions, or coagulation abnormalities in critically ill patients. Mats of interwoven gas exchange fibers from randomly collected MOs (PLS, Maquet, Rastatt, Germany) of 21 patients were stained with antibodies (anti-vWF and anti-P-selectin) and counterstained with 4',6-diamidino-2-phenylindole.

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The ability to maintain information for a short period of time (i.e. working memory, WM) tends to decrease across the life span with large inter-individual variability; the underlying neuronal bases, however, remain unclear.

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Motivation can have invigorating effects on behavior via dopaminergic neuromodulation. While this relationship has mainly been established in theoretical models and studies in younger subjects, the impact of structural declines of the dopaminergic system during healthy aging remains unclear. To investigate this issue, we used electroencephalography (EEG) in healthy young and elderly humans in a reward-learning paradigm.

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Unlabelled: Age-related memory impairments have been associated with structural changes in the dopaminergic system, but the underlying mechanisms remain unclear. Recent work indicates that iron accumulation might be of particular relevance. As iron accumulates, a degeneration of myelin sheaths has been observed in the elderly, but the relationship between both and their impact on memory performance in healthy elderly humans remain important open questions.

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Sense of body ownership and body representation are fundamental parts of human consciousness, but the contribution of the visual modality to their development remains unclear. We tested congenitally and late blind adults on a somatosensory version of the rubber hand illusion, and on the Aristotle illusion, in which sighted controls touching a single sphere with crossed fingers commonly report perceiving two. We found that congenitally and late blind individuals did not report subjectively experiencing the rubber hand illusion.

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Article Synopsis
  • The Sudbury Neutrino Observatory (SNO) used 3He proportional counters to measure neutral-current interactions in heavy water, determining the total active 8B solar neutrino flux with a new method.
  • The measured total flux was found to be 5.54 with specific uncertainties, consistent with earlier findings and standard solar models.
  • A comprehensive analysis of solar and reactor neutrino data suggested a new value for Deltam2 and improved precision in the mixing angle theta compared to earlier SNO results.
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The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra and rates. For charged current events, assuming an undistorted 8B spectrum, the night minus day rate is 14.0%+/-6.

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Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using the neutral current (NC), elastic scattering, and charged current reactions and assuming the standard 8B shape, the nu(e) component of the 8B solar flux is phis(e) = 1.76(+0.

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We measured the 7Be(p,gamma)8B cross section from E(c.m.) = 186 to 1200 keV, with a statistical-plus-systematic precision per point of better than +/-5%.

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Solar neutrinos from (8)B decay have been detected at the Sudbury Neutrino Observatory via the charged current (CC) reaction on deuterium and the elastic scattering (ES) of electrons. The flux of nu(e)'s is measured by the CC reaction rate to be straight phi(CC)(nu(e)) = 1.75 +/- 0.

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In the framework of the tri-annual report to WHO of progress towards "Health for all" the specific question concerning reduction of inequity in health is addressed. Regional variations in health status represent an important aspect of that question which is of particular interest in a federal country where major public health competencies are located at the regional level (cantons in Switzerland). Health status is described by both mortality measures (main causes of death) in the population aged 0-64 years and morbidity indicators (rates of disability pensioners) in the same age group.

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