Regression is an ego defence mechanism which causes the ego to retreat to an earlier stage (specifically the oral stage for schizophrenia). As an adult, most people satisfy oral desires through kissing, smoking or chewing gum. However, if an adult experiences an excessive amount of stress, they may regress back to the oral stage. This causes the ego to retreat to an earlier stage where it is much weaker or doesn’t exist. This leaves the id in overall control of the psyche