Musicians use speech-specific areas when processing tones: The key to their superior linguistic competence?

It is known that musicians compared to non-musicians have some superior speech and language competence, yet the mechanisms how musical training leads to this advantage are not well specified. This event-related fMRI study confirmed that musicians outperformed non-musicians in processing not only of musical tones but also syllables and identified a network differentiating musicians from non-musicians during processing of linguistic sounds. Within this network, the activation of bilateral superior temporal gyrus was shared with all subjects during processing of the acoustically well-matched musical and linguistic sounds, and with the activation distinguishing tones with a complex harmonic spectrum (bowed tone) from a simpler one (plucked tone). These results confirm that better speech processing in musicians relies on improved cross-domain spectral analysis. Activation of left posterior superior temporal sulcus (pSTS), premotor cortex, inferior frontal and fusiform gyrus (FG) also distinguishing musicians from non-musicians during syllable processing overlapped with the activation segregating linguistic from musical sounds in all subjects. Since these brain-regions were not involved during tone processing in non-musicians, they could code for functions which are specialized for speech. Musicians recruited pSTS and FG during tone processing, thus these speech-specialized brain-areas processed musical sounds in the presence of musical training. This study shows that the linguistic advantage of musicians is linked not only to improved cross-domain spectral analysis, but also to the functional adaptation of brain resources that are specialized for speech, but accessible to the domain of music in the presence of musical training.