Supplemental Experimental Procedures: Participants

Subjects did not participate in all the experiments. Fourteen (8m6f; mean age = 21.8 ± 3.1 years) subjects participated in Experiment 1 with the 200-Hz standard. Twenty subjects (10m10f; mean age = 20.2 ± 2.1 years) participated in Experiment 1 with the 400-Hz standard. Fourteen subjects (8m6f; mean age = 22.9 ± 3.7 years) participated in Experiment 2 with the 200-Hz standard. Nineteen subjects (11m8f; mean age = 19.7 ± 1.2 years) participated in Experiment 2 with the 400-Hz standard. Six subjects (4m2f; mean age = 20.0 ± 1.3 years) participated in Experiment 3 with the 100-Hz tactile stimuli. Five subjects (3m2f; mean age = 20.2 ± 1.3 years) participated in Experiment 3 with the 200-Hz tactile stimuli. All subjects reported normal tactile sensibilities and no subjects reported a history of neurological disease. All testing procedures were performed in compliance with the policies and procedures of the Institutiona