What causes SISP?

• It is still unclear exactly what causes people to pick their skin or bite their nails, lips or cheeks. There is some evidence to support a genetic or biological link to the behavior. Skin picking or chewing is seen in the animal kingdom (e.g. dogs) and can cause significant tissue damage. Further, some women report that their picking increases or decreases with their monthly cycle supporting the notion that there may be some chemical or hormonal basis to the behavior.
  
• Some people report picking/biting in an attempt to regulate their activity levels (e.g. when they are bored or overly excited), while others describe picking/biting as a way of making bad feelings such as anxiety or sadness go away. Others describe picking solely as the result of itching. Further, many people with SISP describe picking as a result of a tactile trigger, feeling a bump or irregularity in their skin or a dry piece of skin on the lip makes them want to remove it and, thus, make the area smooth again. Finally, many with SISP report picking for the sheer pleasure of unclogging a pore or removing a substance from their skin. For these folks it is more the substance that is removed from the skin that is the focus of attention, rather than a sensation, emotion or neurological state. In any case, the result of picking seems to be some level of gratification or pleasure, albeit short lived, that drives the behavior.