title: Combining non-invasive transcranial brain stimulation with neuroimaging and electrophysiology: Current approaches and future perspectives.
abstract: Non-invasive transcranial brain stimulation (NTBS) techniques such as transcranial magnetic stimulation (TMS) and transcranial current stimulation (TCS) are important tools in human systems and cognitive neuroscience because they are able to reveal the relevance of certain brain structures or neuronal activity patterns for a given brain function. It is nowadays feasible to combine NTBS, either consecutively or concurrently, with a variety of neuroimaging and electrophysiological techniques. Here we discuss what kind of information can be gained from combined approaches, which often are technically demanding. We argue that the benefit from this combination is twofold. Firstly, neuroimaging and electrophysiology can inform subsequent NTBS, providing the required information to optimize where, when, and how to stimulate the brain. Information can be achieved both before and during the NTBS experiment, requiring consecutive and concurrent applications, respectively. Secondly, neuroimaging and electrophysiology can provide the readout for neural changes induced by NTBS. Again, using either concurrent or consecutive applications, both "online" NTBS effects immediately following the stimulation and "offline" NTBS effects outlasting plasticity-inducing NTBS protocols can be assessed. Finally, both strategies can be combined to close the loop between measuring and modulating brain activity by means of closed-loop brain state-dependent NTBS. In this paper, we will provide a conceptual framework, emphasizing principal strategies and highlighting promising future directions to exploit the benefits of combining NTBS with neuroimaging or electrophysiology.
authors.affiliation: Department of Neurology and Stroke, and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany; Institute for Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; Department of Psychology, Christian-Albrechts-University, Kiel, Germany.
authors.forename: Til Ole
authors.initials: TO
authors.lastname: Bergmann
authors.affiliation: Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.
authors.forename: Anke
authors.initials: A
authors.lastname: Karabanov
authors.affiliation: Department of Psychology, Christian-Albrechts-University, Kiel, Germany; Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
authors.forename: Gesa
authors.initials: G
authors.lastname: Hartwigsen
authors.affiliation: Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark; Department of Electrical Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark; Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Thielscher
authors.affiliation: Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark; Department of Neurology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark. Electronic address: h.siebner@drcmr.dk.
authors.forename: Hartwig Roman
authors.initials: HR
authors.lastname: Siebner
mesh_terms: D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging* / Q000502:physiology*; D001931:Brain Mapping / Q000639:trends*; D004569:Electroencephalography / Q000379:methods; D005544:Forecasting; D006801:Humans; D008959:Models, Neurological; D058765:Neurofeedback; D059906:Neuroimaging / Q000639:trends*; D065908:Transcranial Direct Current Stimulation / Q000639:trends*
keywords: Closed-loop; Electrophysiology; Neuroimaging; Non-invasive transcranial brain stimulation (NTBS); Transcranial current stimulation (TCS); Transcranial magnetic stimulation (TMS)