Answer: Water diffuses into the skin via sweat ducts which alters the electrolyte balance. electrolytes can be salts like sodium and potassium. This alters the stability of neurons causing blood vessels to constrict therefore decreasing the amount of fluid in the fingers which would normally give the skin tension. The decrease causes wrinkles.
Explanation: I had that answer before and it was really hard to understand it, I hope this helps you. Best Of Luck!