1983 journal article by Eugene S. Morton referenced in Ch. 3
From the abstract: "We have long wondered what functions and meanings animal vocalizations have for animals and how these are related to our own unique speech. Since Darwin (1872), biologists have described vocalizations with the view that, once many repertoires are studied, the process of comparing animals' sounds will lead to an understanding of how communication evolves. Since the 1950s the descriptions of sounds have utilized the sound spectrograph..."
From the abstract: "Noise is typically conceived of as being detrimental to cognitive performance. However, given the mechanism of stochastic resonance, a certain amount of noise can benefit performance. We investigate cognitive performance in noisy environments in relation to a neurocomputational model of attention deficit hyperactivity disorder (ADHD) and dopamine."