83 results match your criteria: "University of Graz Universitaetsplatz 2[Affiliation]"

EEG alpha band dissociation with increasing task demands.

Brain Res Cogn Brain Res

July 2005

Institute of Psychology, University of Graz, Universitaetsplatz 2/III, A-8010 Graz, Austria.

In assuming functional differences between different EEG alpha frequency bands, recent studies emphasize the importance of using narrow (8-10 Hz or 10-12 Hz) instead of broad alpha frequency ranges (8-12 Hz). Due to individual differences in alpha activity, it has also been suggested to adjust alpha frequency bands individually for each participant. The present paper highlights the dissociating role of different task demands on the extent of event-related desynchronization (ERD) in different alpha frequency bands.

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Na(+) entry and modulation of Na(+)/Ca(2+) exchange as a key mechanism of TRPC signaling.

Pflugers Arch

October 2005

Institute of Pharmaceutical Sciences, Pharmacology and Toxicology, Karl-Franzens-University of Graz, Universitaetsplatz 2, 8010 Graz, Austria.

Ion channels formed by canonical transient receptor potential (TRPC) proteins are considered to be key players in cellular Ca(2+) homeostasis. As permeation of Ca(2+) through TRPC homo- and/or heteromeric channels has been repeatedly demonstrated, analysis of the physiological role of TRPC proteins was so far based on the concept that these proteins form regulated Ca(2+) entry channels. The well-recognized lack of cation selectivity of TRPC channels and the ability to generate substantial monovalent conductances that govern membrane potential and cation gradients were barely appreciated as a physiologically relevant issue.

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Objective: We examined whether task-related band power changes (event-related desynchronization/synchronization; ERD/ERS) that have been linked to individual differences in cognitive ability demonstrate satisfying temporal stability and cross-situational consistency.

Methods: Multi-channel EEG recordings from 29 adults, assessed at three different occasions over 2 years were examined. Between-session correlations and consistency coefficients (Cronbach's alpha) across the three experiments were evaluated for both, spectral power features of the resting EEG and ERD/ERS estimates while the participants performed some cognitive task (i.

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Gas chromatographic-mass spectrometric analysis of whole body extracts of Platynothrus peltifer, a desmonomatan oribatid mite that belongs to the family Camisiidae, exhibited a basic profile of seven compounds, comprising the monoterpenes neral, geranial, and nerylformate; the aromatics 3-hydroxybenzene-1,2-dicarbaldehyde (= gamma-acaridial) and 2-formyl-3-hydroxybenzyl formate (= rhizoglyphinyl formate), and two unsaturated Cl7-hydrocarbons, 6,9-heptadecadiene and 8-heptadecene. Neryl formate, gamma-acaridial, and rhizoglyphinyl formate were the main components and amounted to 80% of the extracts. With the exception of y-acaridial (relative abundance varied considerably among samples), this chemical profile was consistently present in extracts of P.

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Extraversion and cortical activation during memory performance.

Int J Psychophysiol

May 2005

Institute of Psychology, University of Graz, Universitaetsplatz 2/III, A-8010 Graz, Austria.

In this study we analyzed the influence of the personality dimension extraversion-introversion (E) on the level and topographical distribution of cortical activation. In 62 participants (32 introverts and 30 extraverts), we measured the extent of Event-Related Desynchronization (ERD) in the EEG during performance of a short-term memory (i.e.

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Role of TRP channels in oxidative stress.

Novartis Found Symp

May 2004

Department of Pharmacology and Toxicology, Karl-Franzens-University, University of Graz, Universitaetsplatz 2, A -8010 Graz, Austria.

Increasing evidence suggests a pivotal role of reactive oxygen species (ROS) as well as reactive nitrogen species (RNS) in human pathophysiology. A typical target of ROS/RNS signalling is Ca2+ channels which mediate both long-term as well as acute cellular responses to oxidative stress. We have previously reported that cation channels related to the Drosophila transient receptor potential gene product (TRPC proteins) are likely to serve as redox sensors in the vascular endothelium, and demonstrated that TRPC3 expression is a determinant of the nitric oxide sensitivity of store-operated Ca2+ signalling.

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Event-related alpha band desynchronization is frequently used to analyze spatiotemporal cortical activation patterns during the performance of cognitive tasks. In the present paper the sensitivity of alpha band desynchronization to increasing levels of cognitive load and to different cognitive working memory components is investigated. A 27-channel electroencephalogram of 62 participants while solving (a) a short-term memory and (b) a working memory task (dual task), each with five levels of memory load, was analyzed.

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Serotonin and aggressive motivation in crustaceans: altering the decision to retreat.

Proc Natl Acad Sci U S A

May 1997

Department of Zoology, University Graz, Universitaetsplatz 2, A-8010 Graz, Austria.

In crustaceans, as in most animal species, the amine serotonin has been suggested to serve important roles in aggression. Here we show that injection of serotonin into the hemolymph of subordinate, freely moving animals results in a renewed willingness of these animals to engage the dominants in further agonistic encounters. By multivariate statistical analysis, we demonstrate that this reversal results principally from a reduction in the likelihood of retreat and an increase in the duration of fighting.

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