Neuroscience (or neurobiology) is the scientific study of the nervous system. It is a multidisciplinary branch of biology, that combines physiology, anatomy, molecular biology, developmental biology, cytology, mathematical modeling and psychology to understand the fundamental and emergent properties of neurons and neural circuits. The understanding of the biological basis of learning, memory, behavior, perception and consciousness has been defined as "the ultimate challenge of the biological sciences".
There are three levels of self to consider: the proto, the core, and the autobiographical. The first two are shared with many, many other species, and they are really coming out largely of the brain stem and whatever there is of cortex in those species.
António Damásio (2011) Antonio Damasio: The quest to understand consciousness, Dec. 2011