Look Who’s Talking: The Brain-Skin Connection

Our skin is more than simply the wrapping of our bodies. It has an important job. Skin is, in fact, the largest organ of the body, and comprises about 12-15% of your body weight. It provides a protective barrier between your body and the environment. Beyond it’s protective function, skin is also part of your immune system. It is an immune organ, home to a number of specialized immune cells that guard against intruding organisms and substances.

The skin also contributes to our psychological/emotional state. It is a visual representation of self and others. Its appearance plays a role in our perception of attractiveness and yields clues as to someone’s age and general health. We look for those little imperfections – a stray gray hair, fine lines or wrinkles, acne – to make our assessments. When we look at ourselves in the mirror, we make judgments about ourselves and our appearance. Those judgments translate into positive or negative emotions. What we think about ourselves and what we perceive that others think of us matters.

Like other organs in the body, the skin and brain share a strong bidirectional connection, meaning that they communicate with and influence each other. This relationship has been observed using functional magnetic resonance imaging (fMRI) where brain activity associated with skin stimulation. 

This brain-skin connection may play a significant role in body focused repetitive behaviors such as skin picking. More than just a “habit”, skin picking and excessive grooming may be linked to the brain’s bias towards imperfection and neurochemicals related to mood and feelings of well-being.

The Brain’s Bias

The human brain’s job is to protect the body and keep it functioning optimally. It is hard-wired to defend against potential sources of infection and other harm. It’s also driven to find a healthy partner. It might sound like these are two completely separate functions, but they actually fit together quite logically. Because the brain is biased towards finding imperfection, we pay attention to the appearance of ourselves and others. We actively look for indicators of things like aging and indicators of disease. We make judgements based on that appearance.

Itch is an indicator of infection and potential trigger for picking or scratching. Excessive grooming behavior is thought to have started out as a way for our ancient ancestors to reduce or remove skin pathogens by excessive cleaning, washing or scratching rituals. This grooming behavior created visible damage to the skin resulting in disgust-related rejection and isolation from others. While health-protective, this grooming was also isolating.

For people who pick excessively, their fMRI studies show an activation of certain brain areas when they felt feelings of disgust after observing skin irregularities. These findings suggest that people with skin picking may have a disgust-driven behavioral immune system. They perceive their skin as imperfect in some way and the brain says, “I’ll fix it.” How does that happen?

The Brain-Skin Information Superhighway

The brain communicates lightning fast via various neurotransmitters that are released when it is stimulated in some way. We know that itch results in the activation of certain brain areas in advance of a response. It makes sense then that the brain would respond to stimulation of the skin by picking.

Neurobiological studies suggest that excessive grooming behaviors may be related to serotonin dysregulation. Selective Serotonin Reuptake Inhibitors (SSRIs) have been shown to reduce excessive washing in people with Obsessive Compulsive Disorder (OCD) and skin picking in people with Body Dysmorphic Disorder (BDD). Reducing compulsive behaviors with SSRIs suggests that serotonin dysregulation may play a role in the disorders.

Related to serotonin, glutamatergic dysfunction has been found to be associated with behaviors such as skin picking, hair pulling, and other compulsive or habitual behaviors. N-acetylcysteine (NAC), a glutathione precursor and glutamate modulator, has been shown to significantly boost serotonin and has been mentioned as a possible treatment tool for skin picking and other obsessive compulsive related disorders (OCRDs).

Interestingly, oxytocin, also known as the “love hormone”, has been found to actually increase picking behaviors. While that relationship is unclear, oxytocin is thought to play a role in enhancing bonding and relationships.

The picking response can also be triggered by emotions and self-perceptions. Women who have severe acne have been shown to compulsively pick in response to mood changes and self-perceptions, as well as the perceived perceptions of others. Cognitive therapy can help decrease of the picking and reduce depression and anxiety.

What’s Next?

For someone who picks, dealing with the skin injury and the resulting emotional distress can contribute to feelings of unattractiveness and affect the sense of well-being. In turn, the need to alleviate the emotional distress can give rise to more picking. It is thought that this picking cycle may be related to the need to alleviate feelings of emotional distress and disgust as well as possible serotonin dysregulation and the resulting release of oxytocin and other “feel good” hormones.

Can treatment help? Yes.

People who live with skin picking experience it in different ways. Some struggle with co-occurring mental health disorders that can affect their emotional well-being and treatment process. The literature supports the need for treatment that addresses not only the neurobiological underpinnings of skin picking and similar disorders, but also the emotional impacts of living with the disorder. Individualized, holistic treatment means a more balanced, complete approach that addresses each person’s unique needs and promotes healing.

References

1. Just skin deep — Your immune system at the surface. (2020, May 18). ECR Community. https://ecrcommunity.plos.org/2015/06/05/just-skin-deep-your-immune-system-at-the-surface/

2. Mueller, S. M., Hogg, S., Mueller, J. M., McKie, S., Itin, P., Reinhardt, J., Griffiths, C. E., & Kleyn, C. E. (2017). Functional magnetic resonance imaging in dermatology: The skin, the brain and the invisible. Experimental Dermatology, 26(10), 845-853.  https://pubmed.ncbi.nlm.nih.gov/28109199/

3. Steventon, K. (2021). Deeper Than Skin: Soothing Self-conscious Perceptions. Cosmetics and Toiletries, 136(1), 16-20. https://www.cosmeticsandtoiletries.com/research/consumers-market/article/21835922/faceworkshops-deeper-than-skin-soothing-selfconscious-perceptions

4. Schienle, A., Übel, S. and Wabnegger, A. (2018). Visual symptom provocation in skin picking disorder: an fMRI study. Brain Imaging and Behavior 12(5) 1504-1512. https://link.springer.com/article/10.1007/s11682-017-9792-x

5. Feusner, J. D., Hembacher, E., & Phillips, K. A. (2009). The mouse who couldn't stop washing: pathologic grooming in animals and humans. CNS spectrums, 14(9), 503–513. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2853748/

6. Phillips, K. A., & Hollander, E. (2008). Treating body dysmorphic disorder with medication: evidence, misconceptions, and a suggested approach. Body image, 5(1), 13–27. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2705931/

7. Costa-Campos, L., Herrmann, A. P., Pilz, L. K., Michels, M., Noetzold, G., & Elisabetsky, E. (2013). Interactive effects of N-acetylcysteine and antidepressants. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 44, 125-130.  https://www.sciencedirect.com/science/article/pii/S027858461300042