In the history of American neuroscience, Roger Sperry and his contribution are outstanding. In this book, over twenty of his students, research colleagues and scientific friends, themselves all notable neuroscientists, review fifty years of his tireless experimentation and brilliant theoretical argument, also reviewing their own work in the context of Sperry's contributions to their fields. Sperry's challenging and controversial theories are very much alive in contemporary brain science, cognitive psychology and the philosophy of mind. Curiosity about the most difficult questions, such as those concerning conscious awareness, memory and volition led Sperry from the study of the control of complex patterns in brain circuit growth to discovery of the split brain phenomenon, which illuminated how the two halves of the brain integrate their different functions. In revolutionary tests on patients whose hemispheres had been disconnected to prevent the build-up of severe epileptic seizures, two complementary realms of mind were revealed, one verbal and rational ('left brain') nd the other more spatial, metaphorical and intuitive ('right brain'). He was awarded the Nobel Prize for this work in 1981. Although this book is written for students and researchers in the fields of psychology and neuroscience, it will hold interest for any reader who is curious about the workings of the mind and the brain. Although this book is written for students and researchers in the fields of psychology and neuroscience, it will hold interest for any reader who is curious about the workings of the mind and the brain.