"If musical appreciation is a by-product of a more general pattern-processing propensity of the brain, then why are our senses heightened by pink noises? It is significant that the world around us is full of variations with 1/f spectra. Benoit Mandelbrot has pioneered the study of natural and computer-generated patterns that are scale-free. (He calls them fractals...) Mandelbrot draws attention to the fact that there is a pattern to the noise spectrum displayed by the human nervous system. At the extremities of the body... it tends to be of white-noise form; but, as one approaches closer to the central nervous system and the brain, these variations become 1/f-like. Our nervous system may act as a spectral filter to prevent the brain from being swamped with uninteresting white background noise about the world..."