The mind is a pattern processor. The mental ability to discriminate is based upon contrast. As such, a reference pattern affords finer acuity.
Philosophy is a consistent set of definitions, where each word delimits a concept relativistically. Definitions are themselves contrasts of categorization with neighboring terms.
Selfsame mental pattern play which works entirely within the mind also applies to perception from sensation. Audition is exemplary.
Hearing is the simplest of the senses, as sound is merely a mechanical vibration of amplitude and frequency which the mind translates into loudness and pitch – both relative qualities. The acuity of audition most critically depends upon pitch and its subtle sonic attendants, such as tone.
A background pattern is better than no pattern at all for the mind to distinguish petty pitches. “White noise increases the discriminability of tones spectrally close to each other. Representation of pure tones adapts during noise to improve sensory acuity,” said Swiss neurobiologist Tania Rinaldi Barkat.
Rasmus Kordt Christensen et al, “White noise background improves tone discrimination by suppressing cortical tuning curves,” Cell Reports (12 November 2019). The authors observed neural activity patterns. Their naïve matterist assumption that the brain produces mentation, rather than being coincidental, is wrong; so much for fine mental acuity when laboring under a false assumption.
“Good noise, bad noise: White noise improves hearing,” ScienceDaily (12 November 2019).
Ishi Nobu, Spokes 8: The Hub of Being, BookBaby (2019).