Brain Changes Seen in Women With Skin-Picking, Hair-Pulling Disorders
People affected by excoriation disorder repeatedly pick at their skin, produce significant damage to their tissues during picking episodes and feel significant amounts of emotional/psychological distress or experience a substantially reduced ability to maintain a functional daily routine. Some individuals with the disorder focus their skin-picking behaviors on just one body location, while others focus on multiple locations. In addition, some people with the disorder use implements such as scissors or tweezers to pick their skin, rather than their fingernails. Specific parts of the body frequently targeted by people with excoriation disorder include the legs and feet, the arms and hands, the face and the cuticles.
Some people with excoriation disorder don’t know why they pick their skin or have any consistent awareness of the circumstances that trigger their actions. Others have at least some awareness of their motivations or triggering events. Conscious or not, underlying motivations for repetitive skin-picking include the desire to relieve stress and the desire to avoid or cope with unpleasant emotional states. While positive feelings may occur during skin-picking episodes, guilt and shame frequently appear in the aftermath. Roughly 5 percent of all U.S. adults may qualify for an excoriation disorder diagnosis. Women are far more likely than men to meet the criteria for the condition.
People affected by trichotillomania repeatedly and compulsively pull out their hair and experience notable hair loss in targeted body regions such as the scalp, eyelashes, eyebrows or genitals. Hair-pulling episodes are typically preceded by rising feelings of tension or distress, which drop temporarily after hair-pulling occurs. Feelings of shame or guilt often appear in the aftermath of an episode. Doctors typically diagnose trichotillomania in individuals who have no other mental or physical condition that explains their recurring hair-pulling behavior. Possible contributing factors to any given episode of hair-pulling include stress related to unwanted or unpleasant circumstances and stress related to positive or desired events or situations. Women seek treatment for trichotillomania more often than men and may also develop diagnosable symptoms of the condition substantially more frequently.
Brain Changes in Affected Women
In the study published in Behavioural Brain Research, researchers from the University of Chicago and South Africa’s University of Cape Town and SU/UCT MRC Unit on Anxiety and Stress Disorders used a small-scale project involving 49 women to look for telltale signs of brain alteration in women with excoriation disorder and women with trichotillomania. Seventeen of the participants had diagnosed cases of excoriation disorder, while another 17 had diagnosed cases of trichotillomania. The remaining 15 participants acted as a generally healthy comparison group unaffected by either condition. The women in all three groups underwent brain scanning in the form of an MRI (magnetic resonance imaging) exam.
After reviewing the MRI results, the researchers concluded that the women affected by excoriation disorder had a pattern of brain alteration centered on increased size in certain regions, unusual tissue thickness in some regions and unusual tissue thinness in other regions. In contrast, the women affected by trichotillomania had unusual tissue thinness in a separate brain region largely unchanged in women with excoriation disorder. The brain alteration in the women with excoriation disorder mainly appeared in the pleasure center, which powers the human ability to feel rewarding sensations. However, the brain alteration in women with trichotillomania mainly appeared in a nearby region responsible for memory formation and the ability to remember previously stored visual information.
People with trichotillomania may feel a sense of dissociation or detachment from the self. The study’s authors believe that their findings may help explain this particular symptom of the disorder. They also believe that their findings indicate that excoriation disorder may exert at least part of its effect by changing the perception of rewarding sensations.