The cerebral organization of audiomotor transformations in music

The realization of one’s musical ideas at the keyboard is dependent on the ability to transform sound into movement, a process called audiomotor transformation. Using fMRI, we investigated cerebral activations while classically-trained improvising and non-improvising musicians imagined playing along with recordings of familiar and unfamiliar music excerpts. We hypothesized that audiomotor transformation would be associated with the recruitment of dedicated cerebral networks, facilitating aurally-cued performance. Results indicate that while all classically-trained musicians engage a left-hemisphere network involved in motor skill and action recognition, only improvising musicians additionally recruit a right dorsal frontoparietal network dedicated to spatially-driven motor control.
Mobilization of this network, which plays a crucial role in the real-time transformation of imagined or perceived music into goal-directed action, may be held responsible not only for the stronger activation of auditory cortex we observed in improvising musicians in response to the aural perception of music, but also for the superior ability to play ‘by ear’ which they demonstrated in a follow-up study. The results of this study suggest that the practice of improvisation promotes the implicit acquisition of hierarchical music syntax which is then recruited in top-down manner via the dorsal stream during music performance.
In a study of audiomotor transformation in Parkinson patients, we demonstrated a dissociation between dysprosody in speech and music. While patients’ speech could reliably be distinguished from that of healthy individuals, purely on the basis of aural perception, no difference was observed between patients and healthy controls in their ability to sing improvised melodies.