 The environmental and societal values are central to this new view of the ego, a view that resulted in “the addition of an entire social and cultural dimension to the concept of personality growth.”  Erikson’s benefaction to the knowledge of disordered behavior centers around his concepts of crisis and the importance of crisis resolution during critical periods of development.He proposed eight stages of psychosocial development shown in the table below.Erikson's Psychosocial Stages