Music listening is among of people’s hobbies. Music listening enhances or changes certain neural circuits, including the density of dendritic connections in the primary auditory cortex.
The Harvard neuroscientist Gottfried Schlaug has shown that the front portion of the corpus callosum the mass of fibers connecting the two cerebral hemispheres is significantly larger in musicians than non-musicians, and particularly for musicians who began their training early.
This reinforces the notion that musical operations become bilateral with increased training, as musicians coordinate and recruit neural structures in both the left and right hemispheres.
Several studies have found microstructural changes in the cerebellum after the acquisition of motor skills, such as are acquired by musicians, including an increased number and density of synapses. Schlaug found that musicians tended to have larger cerebellums than non-musicians, and an increased concentration of gray matter; gray matter is that part of the brain that contains the cell bodies, axons, and dendrites, and is understood to be responsible for information processing, as opposed to white matter, which is responsible for information transmission.
Whether these structural changes in the brain translate to enhanced abilities in nonmusical domains has not been proven, but music listening and music therapy have been shown to help people overcome a broad range of psychological and physical problems.
More practically, the results indicate that the environment even when mediated by amniotic fluid and by the womb can affect a child’s development and preferences. So the seeds of musical preference are sown in the womb, but there must be more to the story than that, or children would simply gravitate toward the music their mothers like, or that plays in Lamaze classes.
What I can say is that musical preferences are influenced, but not determined, by what we hear in the womb. There also is an extended period of acculturation, during which the infant takes in the music of the culture she is born into. There were reports a few years ago that prior to becoming used to the music of a foreign culture, all infants prefer Western music to other music, regardless of their culture or race.