Frequency-Dependent Tuning of the Human Motor System Induced by Transcranial Oscillatory Potentials
Year: 2011
Type: article
Abstract: Different corticothalamic brain modules intrinsically oscillate at a "natural frequency" in a topographically organized manner. In "quiescent" human sensorimotor regions, the main detectable oscillatory activity peaks at ∼20 Hz, and partly contributes to determine the state of corticospinal excitability. Here, we showed that the transcranial application of an imperceptible, short-lasting (90 s) electric field oscillating at a physiological range increases corticospinal excitability online, with well defined frequency dependence and regional specificity. Indeed, the size of motor evoked potentials (MEPs) induced by navigated single-pulse TMS over the motor cortex significantly increased only during the local application of transcranial alternating current stimulation (tACS) at 20 Hz (β range). Other tACS frequencies (5, 10, and 40 Hz) applied on the motor cortex did not impact MEPs' size. Moreover, tACS applied on a control site (parietal cortex) and on a peripheral site (ulnar nerve) also failed to modulate MEPs. These results help clarifying the functional significance of the 20 Hz idling β rhythm of sensorimotor regions and suggest potential clinical applications of this approach.
Source: Journal of Neuroscience
Authors: Matteo Feurra, Giovanni Bianco, Emiliano Santarnecchi, Massimiliano Del Testa, Alessandro Rossi, Simone Rossi
Institution: Azienda Ospedaliera Universitaria Senese
Language: English
Subfield: Neurology
Field: Neuroscience
Domain: Life Sciences
Open Access status: hybrid
Funder: European Commission
Award: The Hand Embodied
OpenAlex ID: W2161470754
