Why do individuals with body dysmorphic disorder (BDD) tend to
perceive themselves as disfigured and ugly? It may be due, at least in part,
to visual-processing abnormalities.
Several years ago, for instance, subjects with BDD and healthy control
subjects were presented computerized images of their respective faces. A
number of the BDD subjects, but none of the controls, perceived distortions
that were not present.
But if BDD can be blamed, at least in part, on visual abnormalities, why is
this so? It may be because of abnormal visual processes in the brain, a study
published in the December 2007 Archives of General Psychiatry
suggests. It was headed by Jamie Feusner, M.D., an assistant professor of
psychiatry at the University of California at Los Angeles Department of
Psychiatry and Behavioral Sciences.
Feusner and his team also wanted to find out whether persons with BDD
experience abnormal patterns of brain activation—only this time while
visually processing other people's faces to minimize "the influence of
distorted self-representations and symptom provocation." Their subjects
included 12 individuals with the disorder and 13 control subjects matched by
age, gender, and educational achievement.
The subjects were given facial-perception tasks. During each task, subjects
viewed on a computer screen three digitized photographs of three
neutral-expression faces positioned so there was a target face on top and two
faces on the bottom. They were instructed to "Choose the face [from the
two selections] on the bottom that is the same face as the one on the top, by
pressing the right or the left button." The tasks were designed to be
easy enough that it would be unlikely to result in behavioral differences
between subjects with the disorder and control subjects.
The faces shown during the tasks were either of normal spatial frequency,
high spatial frequency, or low spatial frequency. "Detailed analysis of
facial traits such as edges depicting contours of the nose, eyes, eyelashes,
skin blemishes, and exact shape of the mouth," wrote the authors,"
relies on fine spatial resolution and texture analysis, which is
conveyed by high-spatial-frequency visual information." Configural
aspects of faces such as the general shape of the face and relative position
of the eyes to the mouth are primarily conveyed by low-spatial-frequency
visual information, they added.
The researchers used functional magnetic resonance imaging (fMRI) to
visualize subjects' brain activity as they engaged in various
BDD subjects visually processed faces during the various tasks differently
from control subjects. Most notably, controls used the left hemisphere of the
brain for viewing faces with high spatial frequency, but the BDD subjects used
it not just for that purpose, but also to view faces with low spatial
frequency or normal spatial frequency.
These results suggest that "subjects with BDD demonstrate fundamental
differences from controls in visually processing others' faces," Feusner
and his colleagues concluded. Moreover, "the finding of greater left
hemisphere activations suggest that subjects with BDD may rely more on
extraction and processing of details." And if that is the case, then it
might explain why "patients with BDD often report honing in on details
of their appearance.. .that they perceive are
Furthermore, when BDD subjects looked at high-spatial-frequency faces,
normal-spatial-frequency faces, and low-spatial-frequency faces, their
amygdalae were aroused. This was not the case when control subjects looked at
the same faces.
"We were surprised by this finding," Feusner told
Psychiatric News. "In fact, a previous study in healthy
controls had shown that... even [faces] with fearful expressions do not cause
amygdala activation. We need to perform further studies to better understand
the reason for this abnormal activation."
A more pressing challenge, however, is to find out whether the
visual-processing abnormalities that persons with the disorder experience
while viewing other people's faces also occur when they view their own faces.
Feusner and his team are now trying to answer this question. Another challenge
is to determine whether BDD subjects experience visual-processing
abnormalities only when they view faces or also when they view other things."
We are testing visual processing for objects (houses)," Feusner
Meanwhile, Feusner believes that the study results that they've just
published have important clinical implications. "Information about the
underlying pathophysiology of BDD may be able to help clinicians better
understand it and therefore better identify it in their practice. When
patients seem to home in on small details of their appearance (or aspects that
are difficult to see for outside observers) and are unable to see the 'bigger
picture,' this should be a red flag that the diagnosis may be BDD.
Unfortunately, BDD is often missed in clinical practice."
"This study is just the beginning of a line of research that should
provide more information on the pathophysiology of BDD and how it relates to
the symptomatology," Feusner added. "Ultimately we hope to be able
to use this information to develop new treatments such as perceptual
retraining to help individuals with BDD perceive themselves more
"Dr. Feusner's study is groundbreaking," Katharine Phillips,
M.D., a professor of psychiatry at Brown University and a BDD authority, told
Psychiatric News. "The finding that people with BDD visually
process faces differently from healthy controls provides an important window
on neurobiological processes that may be involved in BDD's pathophysiology,
about which little is known. What's exciting is that this finding may explain
what we see clinically, which is that people with BDD over-focus on minor
details of their appearance that others don't notice. These results are also
compatible with a neuropsychological study of BDD, in which participants
over-focused on isolated details in a complex figure, rather than on large,
global features—in other words, they had trouble seeing the forest for
The study was funded by the National Institute of Mental Health and several
other organizations and foundations.
An abstract of "Visual Information Processing of Faces in Body
Dysmorphic Disorder" is posted at<http://archpsyc.ama-assn.org/cgi/content/abstract/64/12/1417>.▪