Richard D. Granstein said that nearly everyone has some form of stress in their life, so it's difficult to determine whether stress can actually make the skin's appearance worse and it's been known for a long time that the nervous system, which processes our stress, has an impact on conditions such as psoriasis.
He said that research linking the nervous system and the skin has long been understood and if the nerves' path to an area of a patient's skin affected by psoriasis is interrupted, its been observed that the psoriasis improves and the condition also improves if local anesthetic is injected into psoriasis patches. This information strongly suggests that nerves play a role in how psoriasis operates.
Granstein said experimental data support the idea that the nervous system and stress affect inflammatory skin conditions in humans. Many types of cells in the skin, including immune cells and endothelial cells (cells that line blood vessels), can be regulated by neuropeptides and neurotransmitters, which are chemicals released by the skin's nerve endings. Stress can result in the skin's nerve endings releasing an increased level of these chemicals.
When this occurs, it can affect how and at what level our body responds to many important functions, such as sensation and control of blood flow, and can contribute to the symptoms of stress that we feel. In addition, the release of these chemicals can lead to inflammation of the skin.