What about the noise?

In chapter 8, we talk about the frequencies used by different regions of the brain to communicate with each other in processing sound and music. In particular we noted "two particular frequency regions, the theatre (4-8 Hz) and the alpha (8-13 Hz) were found to activate" (173) in music processing. But what about the noise that neuroscientists have to sift through to discern these frequencies? Increasingly in new studies, neuroscientists are discovering fluctuations in the noise that are meaningful and found throughout nature, even in pieces of music: https://www.quantamagazine.org/brains-background-noise-may-hold-clues-to-persistent-mysteries-20210208/ (a number of academic sources are cited in the article detailing current study of this subject).