Increased fronto-temporal connectivity by modified melody in real music

In real music, the original melody may appear intact, with little elaboration only, or significantly modified. Since a melody is most easily perceived in music, hearing significantly modified melody may change a brain connectivity. Mozart KV 265 is comprised of an original melody of “Twinkle Twinkle Little Star” with its significant variations. We studied whether effective connectivity changes with significantly modified melody, between bilateral inferior frontal gyri (IFGs) and Heschl’s gyri (HGs) using magnetoencephalography (MEG). Among the 12 connectivities, the connectivity from the left IFG to the right HG was consistently increased with significantly modified melody compared to the original melody in 2 separate sets of the same rhythmic pattern with different melody ( p = 0.005 and 0.034, Bonferroni corrected). Our findings show that the modification of an original melody in a real music changes the brain connectivity. Significant statements Our data show how a regional connectivity changes when the original melody is intact or significantly modified, consistent in two different sets of variations with the same rhythmic patterns but with the different melody pattern. The present study employed real music of Mozart’s Variation KV 265 as musical stimuli, dissected musical elements in each variation, and devised the two comparable sets of variation, which have the same rhythmic pattern but different melody. We exploited naturalistic conditions in real music instead of devising artificial conditions, and successfully demonstrated how variations of melody in real music change a regional connectivity in the brain.