Everyone checks themselves in the mirror now and then, but that experience can be horrifying for individuals suffering from body dysmorphic disorder, or BDD, a psychiatric condition that causes them to believe, wrongly, that they appear disfigured and ugly. These people tend to fixate on minute details - every tiny blemish looms huge - rather than viewing their face as a whole.
Now researchers at UCLA have determined that the brains of people with BDD have abnormalities in processing visual input, particularly when examining their own face. Further, they found that the same systems of the brain are overactive in both BDD and obsessive-compulsive disorder, suggesting a link between the two. The research appears in the February issue of the journal Archives of General Psychiatry.
"People with BDD are ashamed, anxious and depressed," said Dr. Jamie Feusner, an assistant professor of psychiatry and lead author of the study. "They obsess over tiny flaws on their face or body that other people would never even notice. Some refuse to leave the house, others feel the need to cover parts of their face or body, and some undergo multiple plastic surgeries. About half are hospitalized at some point in their lifetimes, and about one-fourth attempt suicide."
Despite its prevalence - BDD affects an estimated 1 to 2 percent of the population - and severe effects, little is known about the underlying brain abnormalities that contribute to the disease.
To better understand its neurobiology, Feusner and colleagues examined 17 patients with BDD and matched them by sex, age and education level with 16 healthy people. Participants underwent functional magnetic resonance imaging (fMRI) while viewing photographs of two faces - their own and that of a familiar actor - first unaltered, and then altered in two ways to parse out different elements of visual processing.
One altered version included only high-spatial frequency information, which would allow detailed analysis of facial traits, including blemishes and hairs. The other showed only low-spatial frequency information, conveying the general shape of the face and the relationship between facial features.