Parental alienation is a form of relational aggression by one parent against the other parent using their common children. The process can become cyclic with each parent attempting to alienate the children from the other. There is potential for a negative feedback loop and escalation. At other times an affected parent may withdraw leaving the children to the alienating parent. Children so alienated often suffer effects similar to those studied in the psychology of torture. (Sources: External link articles below and late adulthood consciousness of parental alienation)