Silvanto, J. and Cattaneo, Z. 2017. Common framework for “virtual lesion” and state-dependent TMS: the facilitatory/suppressive range model of online TMS effects on behavior Journal: Brain and Cognition. Brain and Cognition. 119, pp. 32-38. https://doi.org/10.1016/j.bandc.2017.09.007
| Title | Common framework for “virtual lesion” and state-dependent TMS: the facilitatory/suppressive range model of online TMS effects on behavior Journal: Brain and Cognition |
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| Authors | Silvanto, J. and Cattaneo, Z. |
| Abstract | The behavioral effects of Transcranial Magnetic Stimulation (TMS) are often nonlinear; factors such as stimulation intensity and brain state can modulate the impact of TMS on observable behavior in qualitatively different manner. Here we propose a theoretical framework to account for these effects. In this model, there are distinct intensity ranges for facilitatory and suppressive effects of TMS – low intensities facilitate neural activity and behavior whereas high intensities induce suppression. The key feature of the model is that these ranges are shifted by changes in neural excitability: consequently, a TMS intensity, which normally induces suppression, can have a facilitatory effect if the stimulated neurons are being inhibited by ongoing task-related processes or preconditioning. For example, adaptation reduces excitability of adapted neurons; the outcome is that TMS intensities which inhibit non-adapted neurons induce a facilitation on adapted neural representations, leading to reversal of adaptation effects. In conventional “virtual lesion” paradigms, similar effects occur because neurons not involved in task-related processes are inhibited by the ongoing task. The resulting reduction in excitability can turn high intensity “inhibitory” TMS to low intensity “facilitatory” TMS for these neurons, and as task-related neuronal representations are in the inhibitory range, the outcome is a reduction in signal-to-noise ratio and behavioral impairment. |
| Journal | Brain and Cognition |
| Journal citation | 119, pp. 32-38 |
| ISSN | 0278-2626 |
| Year | 2017 |
| Publisher | Elsevier |
| Publisher's version | |
| Digital Object Identifier (DOI) | https://doi.org/10.1016/j.bandc.2017.09.007 |
| Publication dates | |
| Published | 28 Sep 2017 |
| Funder | ERC - European Research Council |
| License | CC BY-NC-ND 4.0 |