A comparison of contour and interval processing in musicians and non-musicians using event-related potentials

Musicians and nonmusicians detected infrequent changes to the last note of five-note melodies that either altered the contour (up/down pattern) or the intervals (pitch distance between notes). Robust frontal P3as, reflecting automatic capture of attention, as well as P3bs, reflecting analytic stimulus evaluation, were generated in both contour and interval tasks. These components did not differ across groups for contour, but were smaller and delayed in nonmusicians compared to musicians for interval. However, the topologies were similar for P3a (frontal midline focus) and P3b (parietal midline focus) across groups and tasks, The amplitude of the P3b in musicians was negatively correlated with the age of onset of music lessons. Taken together these findings suggest that (a) contour processing is more basic, (b) interval processing may be more affected than contour by experience, and (c) similar brain networks are involved in generating the P3a and P3b in musicians and nonmusicians.