Psychology is designed to meet scope and sequence requirements for the single-semester introduction to psychology course. The book offers a comprehensive treatment of core concepts, grounded in both classic studies and current and emerging research. The text also includes coverage of the DSM-5 in examinations of psychological disorders. Psychology incorporates discussions that reflect the diversity within the discipline, as well as the diversity of cultures and communities across the globe.Senior Contributing AuthorsRose M. Spielman, Formerly of Quinnipiac UniversityContributing AuthorsKathryn Dumper, Bainbridge State CollegeWilliam Jenkins, Mercer UniversityArlene Lacombe, Saint Joseph's UniversityMarilyn Lovett, Livingstone CollegeMarion Perlmutter, University of Michigan

By the end of this section, you will be able to:

Describe how hunger and eating are regulated
Differentiate between levels of overweight and obesity and the associated health consequences
Explain the health consequences resulting from anorexia and bulimia nervosa

This video segment, adapted from NOVA, documents a ballerina's experience with a potentially deadly eating disorder: anorexia nervosa. Research suggests that a brain chemical called serotonin plays a prominent role in regulating appetite: a key factor in eating disorders. The disruption of serotonin levels by dietary changes can lead to a vicious cycle that prolongs the disorder. By restoring nutrition to her diet, however, the dancer in the video is tackling her eating disorder and resuming her career. [4:29]