Fig 6. Auditory stimulation paradigm.

Each block (~15 sec) included 5–7 different stimuli from the same category (A). The paradigm included 5 blocks of each of the 6 sound categories, for a total duration of 10 min. Blue indicates musical sounds, orange for speech stimuli, and scrambled gray indicates the scrambled version of each category (e.g., Hum-S). The target sound was presented between two randomly selected blocks on five occasions throughout the paradigm. (B-D) Example stimulus in three versions: Song (B), Hum (C) and Speech (D). All stimuli were produced by the same singer. Spectrograms show the frequency structure (y-axis) over time (x-axis), with colors representing the relative amplitude of each frequency band. Left column shows natural categories; right column shows the temporally scrambled condition. “El señor miró el espejo”: “The man looked at the mirror”.