How Bulimia Changes The Brain
Many people with bulimia talk about the addictive nature of the disease.
Aided by brain imaging advances, scientists are looking for evidence that compulsive non-drug behaviors lead to long-term changes in reward circuitry. While we know that certain foods, especially those that are high in sugar have been shown to influence dopamine activity, new research released by psychiatrists at the University of Colorado Hospital confirms that binge-purge behavior seen in bulimia has distinct effects on the brain.
Dr. Guido Frank, psychiatrist at Children’s Hospital in
Colorado found that there is a direct correlation between the number of
binge-purge episodes someone has, and the sensitivity of the brain-reward
Just what is the brain-reward system? Humans are very
susceptible to the anticipation of rewards. They all stimulate the pleasure
center of the human brain. Excessive indulgence into pleasurable activities,
however, seems to decrease dopamine receptor availability. In other words, you
need to increase your participation in such activities in order to achieve the
“It’s a bit like a drug abuse model,” Frank says. “When you
use the drug for the first time you might get excited over it, but then over a
certain time you might become dependent for different reasons, and then the
brain responds less to it.”
Frank studied the brain activities of 41 female
participants. He found that when there was an increase in the binge-purge
episodes, which ranged from three to 70 per week, the less responsive the
brain-reward system became. This means that bulimia causes not only psychological
effects but also biological effects that alter the brain’s reward system,
something researchers have suspected but never before confirmed.
“If you have bulimia, the more often you binge and purge,
the more you probably modify your brain-reward system and then it might be
harder for that reason to get out of it,” Frank said.
Patricia Faris, a gastrointestinal physiologist at the
University of Minnesota, Minneapolis, believes that as with drug addictions,
bulimic behavior is initially voluntary but is transformed into a compulsion
because of changes that it wreaks on the nervous system. Bulimia clearly
affects reward centers: Faris says patients become increasingly depressed and
anxious before episodes; immediately following, they uniformly report a
Bulimia is an eating disorder characterized by obsession
with food and dieting, preoccupation with weight, all-or-nothing thinking, and
rigid dieting behaviors. This stringent dieting results in feelings of
deprivation, hunger and tension. As these feelings build, it becomes harder and
harder to not eat. Binging provides a short-lived way to eat without guilt and
also to modulate emotions, but binge-purge episodes are often followed by
feelings of shame and self-loathing. Food is rarely at the core of the
disorder, but instead is the medium through which it is expressed.Frank is
continuing his research on the brain-reward system and its effects on other
types of eating disorders such as anorexia. In the future, he says there could
be medications that specifically target the affected brain alterations that
occur in a bulimic patient in order to prevent relapse.
This guest post provided by Heidi_PsyD on the Examiner.