Anorexia nervosa: A disorder marked by the pursuit of extreme thinness and by an extreme loss of weight.

Amenorrhea: The absence of menstrual cycles.

Weight set point: The weight level that a person is predisposed to maintain, controlled in part by the hypothalamus.

Bulimia nervosa: A disorder marked by frequent eating binges that are followed by forced vomiting or other extreme compensatory behaviors to avoid gaining weight. Also known as binge-purge syndrome.

Binge-eating disorder: A disorder marked by frequent binges but not extreme compensatory behaviors.

Enmeshed family pattern: A family system in which members are overinvolved with each other’s affairs and overconcerned about each other’s welfare.

Multidimensional risk perspective: A theory that identifies several kinds of risk factors that are thought to combine to help cause a disorder. The more factors present, the greater the risk of developing the disorder.

Ventromedial hypothalamus (VMH): A brain region that depresses hunger when activated.

Lateral hypothalamus (LH): A brain region that produces hunger when activated.

Binge: An episode of uncontrollable eating during which a person ingests a very large quantity of food.

Hypothalamus: A part of the brain that helps maintain various bodily functions, including eating and hunger.