Fig 1.
The timeline of the Experiment 1 and 2.
Participants were asked to perform the Pitch-to-key press matching task (1) and the Baseline (2) task before the TMS stimulation. After that, 1 Hz rTMS was applied over the dorsal premotor cortex (dPMC) and over the primary visual cortex (V1) (3) before the 3 Blocks of training (4). At least 40 minutes after the end of the stimulation (5) participants performed again the pitch-to-key press matching task (6) and the Transfer task (7).
Fig 2.
The auditory-motor mapping of Experiment 1 and Experiment 2.
In Experiment 1 tones were ordered from low to high and corresponded to the spatial position from left to right on the computer keyboard (C = key 1, D = key 2, E = key 3, G = key 4). In Experiment 2 the order of notes was scrambled (E = key 1, C = key 2, G = key 3, D = key 4).
Fig 3.
Diagram of the stimulated site.
The dPMC was located 1 cm medial and 2.5 cm anterior at the same laterality as the motor ‘hot-spot’ (M1), defined as the site where the largest MEPs could be evoked in the relaxed first dorsal interosseus (FDI) muscle. The site for V1 stimulation was localized as the point lying 1.5 cm superior to the inion on the midline.
Fig 4.
Results of the Pitch matching task of Experiment 1 (ordered mapping).
Columns represent average data with standard error bars. The y-axis represents percent correct scores plotted across the TMS site (dPMC and V1). As indicated by the asterisk, TMS over the dPMC significantly reduced participants’ accuracy compared to the V1 stimulation. Horizontal dashed line indicates the level of chance (25%).
Fig 5.
Results of the training phase of the study of Experiment 1.
Graph represents the percentage of pitches correctly played plotted across blocks of trials (Baseline, Block 1, Block 2 and Block 3) for the dPMC and the V1 groups. Error bars represent ±1 SEM.
Fig 6.
Results of the Pitch matching task of Experiment 2 (scrambled mapping).
Columns represent average data with standard error bars. The y-axis represents percent correct scores plotted across the TMS site (dPMC and V1). As indicated by the asterisk, TMS over the dPMC significantly reduced participants’ accuracy compared to the V1 stimulation. Horizontal dashed line indicates the level of chance (25%).
Fig 7.
Results of the training phase of the study of Experiment 2.
Graph represents the percentage of pitches correctly played plotted across blocks of trials (Baseline, Block 1, Block 2 and Block 3) for the dPMC and the V1 groups. As indicated by asterisks, TMS over the dPMC significantly reduced participants’ accuracy in Block 2 and 3 compared to the V1 stimulation. Error bars represent ±1 SEM.