Benefits of Music for Children
Research has shown that music listening increases grey matter volumes in the brain. It is a multi-sensory experience and activates not just the listening centers of the brain but other areas too, like our thinking and emotional centers.
Interestingly, infants who listen to the lullabies sung a capella by their mothers versus a recorded lullaby had better speech sound differentiation. This was not an extensive study, but I feel highlights the significant factor of relationships with parents and caregivers - actual people - and not just relying on the music itself that supports social emotional growth. Meaning... even if you don't have a "singing" voice, babies have a better memory for it and it also creates a nice meaningful interaction between you and your child.
Music can be played throughout the day, as you and your child go through your daily activities. Just remember that your child, especially babies, have delicate ears and hearing. Keep sound levels at an appropriate level.
How do babies respond to different genres of music?
There's no specific evidence to differentiate the genres that babies will or should listen to. What we might need to keep in mind is the volume and context that the music is played. Although, you may notice that some babies might develop a preference for one type over another, and that is okay.