This book explains the theoretical basis of how a person's identity develops from self-concept to personality and a manifest, coherent and congruent identity, and which psychological schemas, e.g. emotional and cognitive schemas, are involved in the disturbance of identity. The connections between ego and the social environment and their influence on the development of the self-concept, personality and identity are presented and the theories of ego consciousness and identity structure are explained. Furthermore, the neurobiology of human social behavior, cognition, identity and the neuroscientific explanations of emotions and emotional processes as well as motivation and motivated behavior are discussed.