Image by bettyx1138 via FlickrAnorexia is not same as loss of appetite. Loss of appetite means there is no hunger for food, whereas anorexia means there is hunger but the person does not like to eat.
Anorexia is typically seen in patients suffering from anorexia nervosa and usually are adolescent girls. They are very much concerned about lean appearance and are afraid of taking food.
Loss of of appetite generally seen in people suffering from any disease starting from common cold to very serious diseases like cancer.
Anorexia nervosa may be due to hormonal disturbances. Now, it has been seen that a feel good hormone, dopamine acts differently in these patients.
Normally, taking food increases dopamine release in the brain, which acts on the reward centre to give good feeling. But, in anorexia nervosa it acts on the part of brain that gives anxious feeling.
This has been substantiated by researcher Walter Kaye, professor of psychiatry at the University of California, San Diego School of Medicine, used a brain imaging technology called positron emission tomography (PET), which permits visualization of dopamine function in the brain.
Imageof Dopamine and Serotonin PathwayThey injected amphetamine, a drug that releases dopamine in the brain; women without eating disorder felt well as released dopamine acted on the reward centre of brain, where as patients of anorexia nervosa felt anxious, and the part of the brain that was activated was, instead, one that worries about consequences.
