Psychosexual development:Freud’s model of psychosexual development
The first stage of psychosexual development is the oral stage, which lasts from the beginning of one’s life up to (about) the 15th month. During this stage, the focus of gratification is on the mouth and pleasure is the result of nursing, but also of exploration of the surroundings (as infants tend to put new objects in their mouths). In this stage the id is dominant, since neither the ego nor the super ego are yet fully formed. Thus the baby does not have a sense of self and all actions are based on the pleasure principle.