Short-interval intracortical inhibition is not affected by varying visual feedback in an isometric task in biceps brachii muscle

Short-interval intracortical inhibition (SICI) of the primary motor cortex (M1) appears to play a significant role in skill acquisition. Consequently, it is of interest to find out which factors cause modulation of SICI. Purpose: To establish if visual feedback and force requirements influence SICI. Methods: SICI was assessed from 10 healthy adults (5 males and 5 females aged between 21 and 35 years) in three submaximal isometric elbow flexion torque levels (5%, 20% and 40% of maximal voluntary contraction [MVC]) and with two tasks differing in terms of visual feedback. Single-pulse and paired-pulse motor evoked potentials (MEPs), supramaximal M-wave and background surface electromyogram (s…