Toshiaki Furukawa1, Minoru Toyokura, Yoshihisa Masakado. 1. Department of Rehabilitation Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan. furukawa@is.icc.u-tokai.ac.jp
Abstract
OBJECTIVE: This study was designed to evaluate the effects of suprathreshold 0.2 Hz repetitive transcranial magnetic stimulation (rTMS) to the prefrontal area and motor cortex on the cerebral cortex excitability. METHODS: The study involved 15 healthy volunteers. With a concave circular coil, rTMS to Fz (bilateral dorsolateral prefrontal areas) was carried out for 100 sessions at a frequency of 0.2 Hz and an intensity 1.2 times the resting motor threshold. In addition, rTMS to M1 (primary motor cortex) (Lt motor hand area) was performed in a similar manner. Before and after rTMS, resting motor threshold, motor evoked potential, cortical silent period (CSP) and F wave were recorded, and their changes after rTMS as compared to the pre-rTMS were analyzed. RESULTS: Neither Fz stimulation nor M1 stimulation caused any significant change in the resting motor threshold, motor evoked potential latency, amplitude or area as compared to the values measured before rTMS. No significant changes were seen in the amplitude and persistence of the F wave. However, while Fz stimulation produced significant prolongation of the CSP duration (p < 0.01), M1 stimulation produced no such prolongation. The sham stimulation (control) showed no significant prolongation of the CSP duration following either M1 or Fz stimulation. CONCLUSION: These results suggest that suprathreshold 0.2 Hz rTMS of Fz induces a significant suppression of excitability in the primary motor cortex.
OBJECTIVE: This study was designed to evaluate the effects of suprathreshold 0.2 Hz repetitive transcranial magnetic stimulation (rTMS) to the prefrontal area and motor cortex on the cerebral cortex excitability. METHODS: The study involved 15 healthy volunteers. With a concave circular coil, rTMS to Fz (bilateral dorsolateral prefrontal areas) was carried out for 100 sessions at a frequency of 0.2 Hz and an intensity 1.2 times the resting motor threshold. In addition, rTMS to M1 (primary motor cortex) (Lt motor hand area) was performed in a similar manner. Before and after rTMS, resting motor threshold, motor evoked potential, cortical silent period (CSP) and F wave were recorded, and their changes after rTMS as compared to the pre-rTMS were analyzed. RESULTS: Neither Fz stimulation nor M1 stimulation caused any significant change in the resting motor threshold, motor evoked potential latency, amplitude or area as compared to the values measured before rTMS. No significant changes were seen in the amplitude and persistence of the F wave. However, while Fz stimulation produced significant prolongation of the CSP duration (p < 0.01), M1 stimulation produced no such prolongation. The sham stimulation (control) showed no significant prolongation of the CSP duration following either M1 or Fz stimulation. CONCLUSION: These results suggest that suprathreshold 0.2 Hz rTMS of Fz induces a significant suppression of excitability in the primary motor cortex.
Authors: Ernest V Pedapati; Donald L Gilbert; Paul S Horn; David A Huddleston; Cameron S Laue; Nasrin Shahana; Steve W Wu Journal: Front Hum Neurosci Date: 2015-02-25 Impact factor: 3.169
Authors: Martin Schecklmann; Michael Landgrebe; Tobias Kleinjung; Elmar Frank; Philipp G Sand; Rainer Rupprecht; Peter Eichhammer; Göran Hajak; Berthold Langguth Journal: BMC Neurosci Date: 2014-06-04 Impact factor: 3.288