Myelin is a fatty substance that coats the axons, speeding up synaptic transmission. Myelanation... is generally completed by age twenty. Multiple sc… - Daniel Levitin

Paul McCartney may be the closest thing our generation has produced to Franz Schubert -- a master of melody, writing tunes anyone can sing, songs that seem to have been there all along. Most people don't realize that "Ave Maria" and "Serenade" were written by Schubert (or that his "Moment Musical in F" so resembles "Martha My Dear"). McCartney writes with similar universality. His "Yesterday" has been recorded by more musicians than any other song in history. Its stepwise melody is deceptively complex, drawing from outside the diatonic scale so smoothly that anyone can sing it, yet few theorists can agree on exactly what it is that McCartney has done.

The story of your brain on music is the story of an exquisite orchestration of brain regions, involving both the oldest and newest parts of the human brain, and regions as far apart as the cerebellum in the back of the head and the frontal lobes just behind your eyes. It involves a precision choreography... between logical prediction systems and emotional reward systems. ...it reminds us of other music we have heard, and it activates memory traces of emotional times of our lives. Your brain on music is all about... connections.

Memory for playing a musical piece... involves a process very much like that for music listening... through establishing standard schemas and expectation. In addition, musicians use chunking... tying information together into groups, and remembering the group as a whole rather than individual pieces.