Kohut's concept of self, and "deficits" in it, is the core variable of self-psychology, Kohut distinguished four key components in the development of the self: the nuclear, virtual, cohesive and grandiose selves.

Normal human infants are born with a nuclear self already in place (a biologically determined psychological entity).' That self encounters 'the virtual self (an image of the newborn's self, which resides in the minds of the infant's parents).'In optimal circumstances, the interaction of nuclear and virtual selves leads to the child's gradual organization of a cohesive self' - to the point where ideally 'a living self in depth has become the organizing center of the ego's activities. However, the appearance of 'the grandiose self...the self that emerges out of the normal infantile experience of oneself as the centre of all experience, omnipotent' comes along the way.

Psychopathology is viewed in regard to how the self adapts and reacts to other objects; This is well defined in Wikipedia:)

http://en.wikipedia.org/wiki/Self_psychology