During the rTMS sessions, subjects were seated in a comfortable c

During the rTMS sessions, subjects were seated in a comfortable chair, and were instructed to keep their eyes closed and try to relax. Subjects selleckchem wore a tight-fitting cap with a 1-cm grid, referenced to the vertex. First, the subject’s resting motor thresholds were measured at the relaxed first dorsal interosseous muscle of the

right hand using surface silver–silver electrodes and single TMS pulses. While searching the cortical first dorsal interosseous muscle representation, TMS stimuli were presented within a 1 × 1-cm array, 5 cm lateral from the vertex. The first dorsal interosseous muscle “hot spot” was identified at the scalp position where TMS induced the highest amplitude motor evoked potentials (MEPs). The resting motor threshold was defined as the lowest intensity capable of evoking five out of 10 MEPs with an amplitude of at least 50 μV in the relaxed muscle. Next, the coil was positioned as close as possible to the right index finger representation in the primary SI as previously described (Ragert et al., 2003, 2004; Tegenthoff et al., 2005). For that purpose, from the “hot spot” of the contralateral first dorsal interosseous muscle, we moved the magnetic coil 2 cm posterior in the parasagittal direction. When stimulating this point, many subjects reported a sensation in an area of the hand and/or finger mostly including

the index finger. After identifying the approximate location of the right index finger representation, the position of the figure-of-eight-shaped coil was fixed. This location is denoted as “SI right index finger” hereinafter. The rTMS intensity was set at 90% of the resting motor threshold. Although the focus of stimulation GKT137831 was clearly remote from the

primary motor cortex, direct or indirect influences from primary motor cortex activation cannot be ruled out. For rTMS, 50 trains of TMS pulses were applied through the tangentially oriented coil grip. A single train consisted of 50 single pulses of 5 Hz lasting 10 s, with an intertrain interval of 5 s. Five consecutive trains were grouped into one block. Between this website each block was a rest period of 1 min. The total stimulation time was 20 min and 40 s. The iHFS protocol was carried out as described by Ragert et al. (2008). iHFS consisted of tactile stimuli (10-ms duration) applied to the distal phalanx of the right index finger (d2). The pulse trains required to drive the stimulators were stored digitally, and played back via an MP3 player, allowing unrestricted mobility of the subjects during the stimulation period. To apply iHFS, a small solenoid (diameter, 8 mm) was taped to the tip of the right index finger, and transmitted the tactile stimuli of the iHFS protocol to the skin. Stimulation trains consisted of 20 single pulses with a frequency of 20 Hz for 1 s, with an intertrain interval of 5 s. The duration of stimulation was 20 min, resulting in a total of 4000 pulses. We studied three experimental groups (Fig. 3).

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