Fig. 1.

Description of the training tasks and overall protocol. A) A schematic illustration of the 2 tasks. Top: Timeline of a trial in the TRO WM task as administered in the magnet pre- and posttraining (nonadaptive version). Participants listened to a sequence of 3 tones (sequence length in the adaptive task practiced by participants increased up to 8 tones). A visual string displaying the expected order of tones in the second sequence was presented 5 s after the onset of the first sequence until the end of the trial. After 5 additional seconds, participants heard another 3-tone sequence, composed of the same tones, and had to determine whether the order of its tones matches the order in the visual string (the illustration is a match). Bottom: Timeline of a trial of the perceptual MM task. Pitch interval between consecutive tones (15, 30, or 60 cents) was constant within a melody. In each trial, 2 MM were presented with a 1-s silent interval between them, and the participant had to determine whether they were identical. B) Overall testing and training protocol: 3 pretraining sessions, 40 training sessions, and 2 posttraining sessions. Pre- and posttraining sessions were identical for the 2 groups.