TY - JOUR U1 - Wissenschaftlicher Artikel A1 - Jooss, Andreas A1 - Haberbosch, Linus A1 - Köhn, Arvid A1 - Rönnefarth, Maria A1 - Bathe-Peters, Rouven A1 - Kozarzewski, Leonard A1 - Fleischmann, Robert A1 - Scholz, Michael A1 - Schmidt, Sein A1 - Brandt, Stephan A. T1 - Motor Task-Dependent Dissociated Effects of Transcranial Random Noise Stimulation in a Finger-Tapping Task Versus a Go/No-Go Task on Corticospinal Excitability and Task Performance JF - Frontiers in Neuroscience N2 - Background and Objective: Transcranial random noise stimulation (tRNS) is an emerging non-invasive brain stimulation technique to modulate brain function, with previous studies highlighting its considerable benefits in therapeutic stimulation of the motor system. However, high variability of results and bidirectional task-dependent effects limit more widespread clinical application. Task dependency largely results from a lack of understanding of the interaction between externally applied tRNS and the endogenous state of neural activity during stimulation. Hence, the aim of this study was to investigate the task dependency of tRNS-induced neuromodulation in the motor system using a finger-tapping task (FT) versus a go/no-go task (GNG). We hypothesized that the tasks would modulate tRNS’ effects on corticospinal excitability (CSE) and task performance in opposite directions. Methods: Thirty healthy subjects received 10 min of tRNS of the dominant primary motor cortex in a double-blind, sham-controlled study design. tRNS was applied during two well-established tasks tied to diverging brain states. Accordingly, participants were randomly assigned to two equally-sized groups: the first group performed a simple motor training task (FT task), known primarily to increase CSE, while the second group performed an inhibitory control task (go/no-go task) associated with inhibition of CSE. To establish task-dependent effects of tRNS, CSE was evaluated prior to- and after stimulation with navigated transcranial magnetic stimulation. Results: In an ‘activating’ motor task, tRNS during FT significantly facilitated CSE. FT task performance improvements, shown by training-related reductions in intertap intervals and increased number of finger taps, were similar for both tRNS and sham stimulation. In an ‘inhibitory’ motor task, tRNS during GNG left CSE unchanged while inhibitory control was enhanced as shown by slowed reaction times and enhanced task accuracy during and after stimulation. Conclusion: We provide evidence that tRNS-induced neuromodulatory effects are task-dependent and that resulting enhancements are specific to the underlying task-dependent brain state. While mechanisms underlying this effect require further investigation, these findings highlight the potential of tRNS in enhancing task-dependent brain states to modulate human behavior. KW - - KW - random noise stimulation KW - transcranial electrical stimulation KW - task dependency KW - finger-tapping task KW - go/no-go task KW - corticospinal excitability KW - neuroplasticity Y1 - 2019 UN - https://nbn-resolving.org/urn:nbn:de:gbv:9-opus-32403 SN - 1662-453X SS - 1662-453X U6 - https://doi.org/10.3389/fnins.2019.00161 DO - https://doi.org/10.3389/fnins.2019.00161 VL - 13 PB - Frontiers Media S.A. ER -