Continuation tapping to triggered melodies: motor resonance effects of melodic motion.

Common Coding theory predicts that perceived action should resonate in produced action to which it bears some resemblance. Here we show that the qualities of motion commonly attributed to melodies are instantiated in motor plans that control timed movements. Participants attempted to tap a steady beat. Each tap triggered a sounded tone, and successive tones were systematically varied in pitch to form short melodies. Tapping behavior was monitored with motion capture. Although instructed to ignore them, triggered tones systematically affected timing and finger movement. When slower melodic motion was implied by a contour change or a smaller pitch displacement, the interval-tap interval (ITI) was longer. When faster melodic motion was implied by a preserved pitch contour or a larger pitch displacement, ITI was shorter. Kinematic recordings suggested that ITI Error arose from an initial failure to disambiguate perception (i.e., velocity implied by melodic motion) from action (i.e., finger velocity [FV]). Early in the tap trajectory, slower FV was associated with longer ITI and faster FV was associated with shorter ITI. These associations were reversed near mid-trajectory, suggesting a transition from execution of motor planning to online control (Glover et al. in Exp Brain Res 154:103-108, 2004).