FOR 5429:  Modulation of brain networks for memory and learning by transcranial electrical brain stimulation: A systematic, lifespan approach

• Subject Area: Medicine
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 467143400

Non-invasive transcranial direct current stimulation (tDCS) has recently received substantial attention in experimental and clinical science, because it allows modulation of human brain function without significant adverse effects. However, despite widespread and often successful use of this technique, little systematic research into the mechanisms underlying frequently observed highly variable effects of tDCS has been accomplished. Currently, this results in suboptimal use of this promising technique in experimental and clinical contexts. The overarching objective of the proposed Research Unit (RU) is to address this knowledge gap by investigating tDCS effects for the first time in a systematic, comprehensive and coordinated way, by a multidisciplinary and complementary team of leading experts in their respective fields. Due to its exceptional relevance for experimental and translational research, human learning and memory function will serve as a model to study tDCS effects across four functional domains (i.e., visual-spatial, language, motor, and executive) and across the human lifespan. Eight empirical projects (Projects P1-8; two per domain) will use comparable methods, individualized and targeted stimulation, highly controlled experimental settings, and tDCS application during concurrent functional imaging to investigate behavioral and neural mechanisms and predictors of stimulation response. Two overarching projects (P9, P10) will (1) relate the outcomes of biophysical models of individualized current flow to behavioral and neural modulations using the large, coordinated dataset acquired in the empirical projects and (2) cross-validate and improve current flow simulations by using in-vivo magnetic current density imaging measurements. A final project (P11) will be concerned with macro-level analyses using advanced data mining methods (i.e., machine learning, artificial intelligence) to reveal shared and differential effects and predictors of tDCS effects on behavior and brain function across projects, functional domains, and the human lifespan. Collaborative activities within the RU will be facilitated by the coordination project that is also responsible for cross-project data management and sharing by adhering to highest standards in the field.In sum, the proposed RU will generate fundamental insights into the neural mechanisms and predictors of tDCS response across the human lifespan, thereby informing theoretical concepts of the mechanisms-of-action by which current flow alters neural activity. From a methodological point of view, we will be able to optimize and validate biophysical models of current flow using an unprecedented dataset. Together, this will substantially advance future experimental and translational applications of tDCS in health and disease.

• DFG Programme: Research Units
• International Connection: Denmark, Israel

Projects

• Coordination Funds (Applicant Flöel, Agnes )
• Enhancing cerebellar-dependent motor learning by focalized tDCS (Applicant Timmann-Braun, Dagmar )
• Enhancing learning-based cognitive control by focalized transcranial direct current stimulation (Applicants Fischer, Rico ;  Meinzer, Marcus )
• Enhancing motor sequence learning by focalized transcranial direct current stimulation (Applicant Nitsche, Michael A. )
• Enhancing novel word learning by focalized transcranial direct current stimulation (Applicant Meinzer, Marcus )
• Enhancing spatiotactile working memory by focalized transcranial direct current stimulation (Applicant Blankenburg, Felix )
• Enhancing value-based learning by focalized tDCS (transcranial direct current stimulation) (Applicant Li, Ph.D., Shu-Chen )
• Enhancing verbal working memory by focalized tDCS (Applicant Hartwigsen, Gesa )
• Enhancing visual-spatial learning by focalized transcranial direct current stimulation (Applicant Flöel, Agnes )
• Optimization of focal brain stimulation by individualized electric field simulations: Implementation and assessment of effects across sites and functional domains (Applicants Antonenko, Daria ;  Thielscher, Ph.D., Axel )
• Validating and optimizing personalized current flow simulations across the human lifespan using in-vivo magnetic resonance current density imaging (Applicant Thielscher, Ph.D., Axel )

• Spokesperson: Professorin Dr. Agnes Flöel