000K utf8 1100 $c2021 1500 eng 2050 urn:nbn:de:gbv:8:3-2021-00586-6 3000 Splittgerber, Maike 4000 Investigation of Methodological and Physiological Factors Influencing Non-Invasive Transcranial Electrical Brain Stimulation$hChristian-Albrechts-Universität zu Kiel [Splittgerber, Maike] 4030 Kiel$nChristian-Albrechts-Universität zu Kiel 4209 Non-invasive transcranial electrical brain stimulation (tES) techniques, including transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS) and transcranial random noise stimulation (tRNS), can alter neuronal activity and related brain functions. However, tES effects seem to be modulated by various influencing factors, leading to high inter-individual variability in tES effects and often only low effect sizes, or even no effects. The present thesis therefore aimed to investigate methodological and physiological influencing factors of tDCS, tACS and tRNS that have not been sufficiently examined so far. A first study investigated the influence of montage and individual functional performance level on the effects of anodal tDCS over the left dorsolateral prefrontal cortex (DLPFC) in healthy adults. Compared with sham stimulation, a multichannel montage led to stronger effects than a bipolar montage. For both montages the effects of stimulation were dependent on the functional performance level of participants. A second study investigated the effects of multichannel tDCS over the left DLPFC in healthy children and adolescents, considering the influence of concurrent target task performance during stimulation and individual head anatomy. tDCS did not influence the target outcome but led to transfer effects on non-target task performance and neurophysiological activity, that were only partly influenced by task performance during stimulation. The individual head anatomy had no influence on stimulation effects. A third study investigated tACS and tRNS effects on motor cortex excitability in healthy children and adolescents in comparison to adults. The individual response to sham stimulation was investigated as marker for the individual physiological brain state. Motor cortex excitability was not modulated by age but by individual response to sham stimulation. All studies provide important insights into the modulatory factors of stimulation effects. Based on these results, future studies should aim at individualising tES application. 4950 https://nbn-resolving.org/urn:nbn:de:gbv:8:3-2021-00586-6$xR$3Volltext$534 4961 https://macau.uni-kiel.de/receive/macau_mods_00001661 5051 150 5550 brain stimulation 5550 cognitive neuroscience 5550 EEG 5550 tACS 5550 tDCS 5550 tRNS