MELODY AS PROSODY: TOWARD A USAGE-BASED THEORY OF MUSIC Thomas M. Pooley Gary A. Tomlinson Rationalist modes of inquiry have dominated the cognitive science of music over the past several decades. This dissertation contests many rationalist assumptions, including its core tenets of nativism, modularity, and computationism, by drawing on a wide range of evidence from psychology, neuroscience, linguistics, and cognitive music theory, as well as original data from a case study of Zulu song prosody. An alternative biocultural approach to the study of music and mind is outlined that takes account of musical diversity by attending to shared cognitive mechanisms. Grammar emerges through use, and cognitive categories are learned and constructed in particular social contexts. This usage-based theory of music shows how domain-general cognitive mechanisms for patterning-finding and intention-reading are crucial to acquisition, and how Gestalt principles are invoked in perception. Unlike generative and other rationalist approaches that focus on a series of idealizations, and the cognitive `competences' codified in texts and musical scores, the usage-based approach investigates actual performances in everyday contexts by using instrumental measures of process. The study focuses on song melody because it is a property of all known musics. Melody is used for communicative purposes in both song and speech. Vocalized pitch patterning conveys a wide range of affective, propositional, and syntactic information through prosodic features that are shared by the two domains. The study of melody as prosody shows how gradient pitch features are crucial to the design and communicative functions of song melodies. The prosodic features shared by song and speech include: speech tone, intonation, and pitch-accent. A case study of ten Zulu memulo songs shows that pitch is not used in the discrete or contrastive fashion proposed by many cognitive music theorists and most (generative) phonologists. Instead there are a range of pitch categories that include pitch targets, glides, and contours. These analyses also show that song melody has a multi-dimensional pitch structure, and that it is a dynamic adaptive system that is irreducible in its complexity.