KQED News Mind/Shift – Dave Davies 
Dr. Thomas Boyce, an emeritus professor of pediatrics and psychiatry at the University of California, San Francisco, has treated children who seem to be completely unflappable and unfazed by their surroundings — as well as those who are extremely sensitive to their environments. Over the years, he began to liken these two types of children to two very different flowers: dandelions and orchids. (more)