A group of behavior patterns occurring in childhood and adolescence that are less severe than psychoses but more resistant to treatment than transient situational disturbances because they are more stabilized and internalized. They are characterized by over-activity, inattentiveness, shyness, feelings of rejection, over-aggressiveness, timidity, or delinquency. The child who frequently runs away from home or who persistently lies, steals, and teases other children in a hostile fashion falls into this category.