Recent U.S. literature has both been informed by, and critically engaged with, materialist conceptions of selfhood. Over the past decades, disciplines like neuroscience and evolutionary biology have increasingly recast the human self as a malleable construct produced by physiological processes. In a parallel development, literary authors have created their own conceptions of somatic subjectivity in conjunction or contrast with scientific and medical discourses. Subjects of Substance examines the forms, functions, and effects of materialist models of mind in selected memoirs and novels. Authors discussed include Michael W. Clune, Don DeLillo, Kay Redfield Jamison, Siri Hustvedt, Richard Powers, Elyn R. Saks, and David Foster Wallace.