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bioRxiv · 10.1101/2023.07.31.551253

Electrical field based dosing improves non-invasive brain stimulation

Numssen, O.·Kuhnke, P.·Weise, K.·Hartwigsen, G.
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Abstract

AbstractTranscranial magnetic stimulation (TMS) is an invaluable non-invasive brain stimulation (NIBS) technique to modulate cortical activity and behavior, but high within- and between-participant variability limits its efficacy and reliability. Here, we explore the potential of electric field (e-field) based TMS dosing to reduce its variability and discuss current challenges as well as future pathways. In contrast to previous dosing approaches, e-field dosing better matches the stimulation strength across cortical areas, both within and across individuals. Challenges include methodological uncertainties of the e-field simulation, target definitions, and comparability of different stimulation thresholds across cortical areas and NIBS protocols. Despite these challenges, e-field dosing promises to substantially improve NIBS applications in neuroscientific research and personalized medicine. Outstanding Questions Box O_TEXTBOXOutstanding Questions O_LIDoes the cortical threshold for effective stimulation differ between primary regions and higher-level association areas? How large is the impact of cytoarchitectonic differences between regions on a stimulation threshold? C_LIO_LIDo cortical stimulation thresholds differ across individuals? Are thresholds stable within an individual across the lifespan? What are the physiological factors influencing these thresholds? C_LIO_LICan a cortical stimulation threshold measured with single-pulse TMS be transferred to repetitive TMS protocols for the study of cognition? C_LIO_LIHow does the cortical stimulation threshold interact with the current brain state? C_LI C_TEXTBOX Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=102 SRC="FIGDIR/small/551253v2_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@16d6e44org.highwire.dtl.DTLVardef@1626d90org.highwire.dtl.DTLVardef@10713e7org.highwire.dtl.DTLVardef@1abdcaa_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Numssen, O., Kuhnke, P., Weise, K., Hartwigsen, G.. 2023-08-02. Electrical field based dosing improves non-invasive brain stimulation. https://doi.org/10.1101/2023.07.31.551253

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