MEP facilitation ratio. MEP facilitation ratio (n = 17) (paired-pulse MEP amplitude at 2.5 ms interstimulus intervals (ISI) /single-pulse MEP) for TMS delivery times at two fixed intervals (200 ms and 800 ms) calculated from the time the pulses were delivered during grasping preparation. Panels (A) and (B) show changes in MEP amplitude recorded from the right first dorsal interosseous (FDI) (A) or the right abductor digiti minimi (ADM) (B) muscles. TMS was delivered after object presentation. Error bars represent the S.E.M.