Using Brain State-dependent Transcranial Magnetic Stimulation for Investigating Causal Role of Cortical Oscillations in Functional States
Andraz Matkovi, Jure Bon, Zvezdan Pirtošek Clinical Department of Neurology, University Medical Centre Ljubljana, Zaloška cesta 2, Ljubljana & Department of Psychology, Faculty of Arts, Aškereva 2, Ljubljana & Clinical Department of Neurology, University Medical Centre Ljubljana, Zaloška cesta
Abstract: Non-invasive brain stimulation is being used for manipulation of cortical oscillations in research and clinical context for development of possible therapeutic applications in brain disorders. Effects of brain stimulation show strong inter- and intra-individual variation. In general there are several sources of this variability, e.g. neuroanatomical and neurochemical factors. This article describes our work in the scope of EkoSMART consortium on development of peripheral sensing techniques. Here we focus on the rapidly varying neurophysiological factors – cortical oscillations. Current state of
cortical oscillations can be continually recorded with peripheral sensors like EEG scalp electrodes and used online for
continuous monitoring and adjustments of brain stimulation parameters. By adjusting the timing, intensity and frequency of
transcranial stimulation to specific brain states it is possible to reduce variation in the treatment effects. However, since brain
state-dependent stimulation (BSDS) requires online monitoring and analysis of neurophysiological data, it is technically
demanding. BSDS has been made possible by recent technological advances and advances in analytical procedures. While
EEG data has been traditionally analyzed in time- or frequency-domain only, time frequency analysis is being increasingly
used and it offers better insight into neurophysiology of oscillations. BSDS is useful in the field of clinical neuroscience,
where it can be used to personalize stimulation parameters, e.g. adjust deep brain stimulation depending on the severity in symptoms in Parkinson’s disease. Because it enables manipulation of cortical oscillations when a specific brain state is detected, it allows stronger causal inferences about their role in behavior and brain states. Therefore, BSDS can be also used as a tool for verification or falsification of hypotheses in cognitive neuroscience.
Keywords: Brain State-dependent Stimulation, Transcranial Magnetic Stimulation, Time-frequency Analysis, Electroencephalography, Cortical Oscillations Using Brain State-dependent Transcranial Magnetic Stimulation for Investigating Causal Role of Cortical Oscillations in Functional States
References:[1] Berger, B. (2014). EEG oscillatory phase-dependent markers of corticospinal excitability in the resting brain. BioMed Research
International. 2014, (2014). DOI: https://doi.org/10.1155/2014/936096.
[2] Bergmann, T. O. (2012). EEG-guided transcranial magnetic stimulation reveals rapid shifts in motor cortical excitability during
the human sleep slow oscillation. Journal of Neuroscience. 32, 1 (2012), 243–253. DOI: https://doi.org/10.1523/JNEUROSCI.4792-
11.2012.
[3] Bergmann, T. O. (2016). Combining non-invasive transcranial brain stimulation with neuroimaging and electrophysiology:
Current approaches and future perspectives. NeuroImage. 140, (2016), 4–19. DOI: https://doi.org/10.1016/j.neuroimage.2016.02.
012.
[4] Brittain, J. S. (2013). Tremor suppression by rhythmic transcranial current stimulation. Current Biology. 23, 5 (2013), 436–440.
DOI: https://doi.org/10.1016/j.cub.2013.01.068.
[5] Cohen, M. X. (2014). Analyzing neural time series data: theory and practice. The MIT Press, Cambridge, Massachusetts.
[6] Gharabaghi, A. (2014). Coupling brain-machine interfaces with cortical stimulation for brain-state dependent stimulation:
enhancing motor cortex excitability for neurorehabilitation. Frontiers in Human Neuroscience. 8, March (2014), 1–7. DOI: https:/
/doi.org/10.3389/fnhum.2014.00122.
[7] Hartmann, T. et al. 2011. Probing of brain states in real-time: Introducing the Console environment. Frontiers in Psychology.
2, MAR (2011), 1–17. DOI: https://doi.org/10.3389/fpsyg.2011.00036.
[8] Horschig, J. M. (2014). Hypothesis-driven methods to augment human cognition by optimizing cortical oscillations. Frontiers
in Systems Neuroscience. 8, June (2014), 1–21. DOI: https://doi.org/10.3389/fnsys.2014.00119.
[9] Jensen, O. (2011). Using brain-computer interfaces and brain-state dependent stimulation as tools in cognitive neuroscience.
Frontiers in Psychology. 2, MAY (2011), 1– 11. DOI: https://doi.org/10.3389/fpsyg.2011.00100.
[10] Karabanov, A. et al. 2016. Transcranial brain stimulation. Current Opinion in Neurology. 29, 4 (2016), 397–404. DOI: https:/
/doi.org/10.1097/WCO.0000000000000342.
[11] Kraus, D. (2016). Brain state-dependent transcranial magnetic closed-loop stimulation controlled by sensorimotor
desynchronization induces robust increase of corticospinal excitability. Brain Stimulation. 9, 3 (2016), 415–424. DOI: https://
doi.org/10.1016/j.brs.2016.02.007.
[12] Little, S. (2013). Adaptive deep brain stimulation in advanced Parkinson disease. Annals of neurology. 74, 3 (2013), 449–57.
DOI: https://doi.org/10.1002/ana.23951.
[13] Ngo, H. V. V. (2013). Auditory closed-loop stimulation of the sleep slow oscillation enhances memory. Neuron. 78, 3 (2013),
545–553. DOI: https://doi.org/10.1016/j.neuron.2013.03.006.
[14] Osipova, D. (2006). Theta and gamma oscillations predict encoding and retrieval of declarative memory. Journal of
Neuroscience. 26, 28 (2006), 7523–7531. DOI: https://doi.org/10.1523/JNEUROSCI.1948-06.2006.
[15] Schulz, H. (2014). Now I am ready - Now I am not: The influence of pre-TMS oscillations and corticomuscular coherence on
motor-evoked potentials. Cerebral Cortex. 24, 7 (2014), 1708–1719. DOI: https://doi.org/10.1093/cercor/bht024.
[16] Veniero, D. (2009). TMS-EEG co-registration: On TMSinduced artifact. Clinical Neurophysiology. 120, 7 (2009), 1392–1399.
DOI: https://doi.org/10.1016/j.clinph.2009.04.023.
[17] Walter, A. (2012). Coupling BCI and cortical stimulation for brain-state-dependent stimulation: methods for spectral estimation
in the presence of stimulation after-effects. Frontiers in Neural Circuits. 6, November (2012), 1–17. DOI: https://doi.org/
10.3389/fncir.2012.00087.