Effect of slow rTMS of motor cortex on the excitability of the Blink Reflex: A study in healthy humans

Effect of sub-threshold 1Hz rTMS over left M1 on corticospinal excitability as indexed by the MEP maximal amplitude recorded from the contralateral relaxed FDI muscle. Each column represents mean maximal amplitude of MEPs of subjects at the baseline (black column) and after rTMS at short (30s, dark grey column), medium (15min, light grey column) and long term (60min, white column). Error bars equal one fold SE.

(A) Mean (±SE) Blink Reflex recovery curve in basal condition, at short (30s), medium (15min) and long (60min) terms after real rTMS. The percentage area of the test iR2 (vertical axis) is represented as a function of the ISI (horizontal axis). Basal curve is represented with diamonds, short-term curve is represented with triangles, medium-term curve is represented with squares and long-term curve with circles. (B) Mean (±SE) Blink Reflex recovery curve in basal condition and at short term (30s) after sham rTMS. The percentage area of the test iR2 (vertical axis) is represented as a function of the ISI (horizontal axis). Basal curve is represented with diamonds and short-term curve is represented with triangles.

(A) Recovery of the R2 response of the Blink Reflex in a representative subject at short term (30s) after sham rTMS. Conditioning and test R2 at ISI 1500ms are represented. The averaged results are in the upper trace and the rectified superimposed responses are in the lower traces. (B) Recovery of the R2 response of the Blink Reflex (SO stimulus contralateral to rTMS) in a representative subject at short term (30s) after real rTMS. Conditioning and test R2 at ISI 1500ms are represented. The averaged results are in the upper trace and the rectified superimposed responses are in the lower traces. (C) Recovery of the R2 response of the Blink Reflex (SO stimulus ipsilateral to rTMS) in a representative subject at short term (30s) after real rTMS. Conditioning and test R2 at ISI 1500ms are represented. The averaged results are in the upper trace and the rectified superimposed responses are in the lower traces.