Relative amplitude of MEPs recorded from the 1DI during a 10% maximum voluntary contraction either during a precision grip (circles) or a power grip (squares). A, during a precision grip, the resting PMv–M1 inhibition turned into facilitation at both the 6 and 8 ms C–T intervals, whereas, during a power grip this inhibition was cancelled. B, during grasp, M1–M1 interactions showed a reduced SICI compared to at rest, irrespective of the type of grasp. The error bars show 1 s.d.