Review Question - QID 214586

A 21-year-old woman presents to a new primary care physician asking for a referral to a plastic surgeon. She states that she has a 5-year history of extreme unhappiness due to the appearance of her stomach. She spends hours per day looking in the mirror at her stomach and says with disgust that it is misshapen and needs to be fixed with surgery. She has tried extreme fasting, exercise, binge eating, vomiting, and taking laxatives, but none of these methods have worked in relieving her anxiety. She says that she has read "almost every website on the internet" about how to fix her stomach and has come to the conclusion that the only solution is surgery. Physical exam reveals a thin woman with a BMI of 19.2 kg/m^2 and a normal-appearing nontender abdomen. Which of the following is the most likely cause of this patient's symptoms?