Fig. 1

Tactile stimulation paradigm. a A Brain Gauge two-digit vibrotactile stimulator was used for stimulus generation. b Schematic of the passive tactile stimulation. Trains of 6 tactile stimuli were delivered simultaneously to the right-hand digit 2 and digit 3. In the long ISI condition stimuli were delivered further apart in time (ISI of 1050 ms), while in the short ISI condition stimuli were presented closer together (ISI of 150 ms) which typically leads to a reduction in somatosensory cortex response. Each stimulus train was separated from the next by 5 ± 0.5 s