RT Journal Article
SR Electronic
T1 Frequency-Dependent Tuning of the Human Motor System Induced by Transcranial Oscillatory Potentials
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 12165
OP 12170
DO 10.1523/JNEUROSCI.0978-11.2011
VO 31
IS 34
A1 Matteo Feurra
A1 Giovanni Bianco
A1 Emiliano Santarnecchi
A1 Massimiliano Del Testa
A1 Alessandro Rossi
A1 Simone Rossi
YR 2011
UL http://www.jneurosci.org/content/31/34/12165.abstract
AB 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.