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Updated: Dec 15, 2025

Measuring Contralateral Silent Period Induced by Single-Pulse Transcranial Magnetic Stimulation to Investigate M1 Corticospinal Inhibition
Published on: August 23, 2022
Modulation of the excitatory phase following the cutaneous silent period by vibration
Ayşegül Gündüz1, Selahattin Ayas2, Markus Kofler3
1Department of Neurology, Cerrahpasa School of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey.
Introduction:
The post-inhibition excitatory phase (E3) of the cutaneous silent period (CSP) is attributed to the resynchronization of motoneuron activity following the inhibitory period but there is also evidence that a somatosensory startle reflex may contribute to this phase. We hypothesized that the startle reflex component contained in E3 will decrease during vibration.
Methods:
Sixteen healthy individuals were included in the study. CSP was recorded from slightly contracted right thenar muscles after painful index finger stimulation, before, during, and immediately after vibration. The values of the percentage change of E3 relative to pre-stimulus baseline (E3%) were compared before, during, and after vibration for each individual.
Results:
There was a reduction in E3% during vibration and the values returned to normal immediately after vibration (153.1 ± 43.5%, 115.2 ± 30.2%, 154.9 ± 68.2%, respectively; p = 0.030).
Discussion:
E3 is reduced during vibration in healthy individuals, presumably due to suppression of a reflex component, which is superimposed upon the known resynchronization of motoneurons.
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