The Psychology of Eating: From Healthy to Disordered Behavior

Eating Disorders 241

through reinforcement and association, and established and perpetuated
by cognitive dysfunctions.

Bulimia nervosa
Concepts from behaviorism have also been applied to bulimia in ways which
parallel the models of anorexia. For example, anxiety reduction models
(Mowrer, 1960; Rosen and Leitenberg, 1982) suggested that vomiting and
purging reduce anxiety, which reinforces this compensatory behavior.
Like behavioral models of anorexia, this approach has been criticized for
explaining only the maintenance and not the cause of the problem and for
including cognitions only implicitly (de Silva, 1995). The first model to
provide a coherent cognitive behavioral formulation of bulimia nervosa was
by Fairburn, Cooper, and Cooper (1986), who described the following
factors as central: low self-esteem, overconcern about shape and weight,
extreme dieting, binge eating, and compensatory self-induced vomiting or
laxative use. The model was then extended in Wilson’s cognitive-social learn-
ing model (1989). Wilson’s analysis described the following five factors:

• Cognitionsabout weight, shape, and food, and dysfunctional thinking


• Fearof weight gain and becoming fat


• Binge eatingfollowed by periods of food restriction which are facilitated
  by low mood, anger, or stress


• Purginginvolving vomiting, laxative abuse, or periods of excessive
  food denial


• Postpurge psychological effectsinvolving two stages. First the individual
  feels both physical and psychological relief. Second they feel worry about
  the psychological and physical consequences, make promises never to
  do it again (“purification promise”), and then increase their dietary
  restraint.

This model parallels that of dietary restraint, described in detail in
chapter 7, which emphasized the central place of periods of food restriction
followed by violation of dietary rules (Herman and Polivy, 1975). It is also
reflected in the “spiral model of eating disorders” (Heatherton and Polivy,
1991) which described the transition from dieting to disordered eating
through dietary failure, reduced self-esteem, and lowered mood.
The transition from dieting to eating disorders is illustrated by the
bestselling The Beverly Hills Diet(Mazel, 1981), which described how Judy
Mazel started dieting when she was 8 years old and how by the time she