Giant Ginkgo

A crucial reason nature might have endowed people with two different sets of nerves is that the slow fibers function from the earliest hours of life, perhaps even in the womb, while the fast fibers develop slowly after birth.

Newborn infants might be able to feel the love in a parent's touch before they can feel the touch itself.

Referring to studies showing that babies need physical contact and nurturing, the group of scientists wrote, "The profound importance of such a system for human well-being has long been suggested, at least since the classical study of baby monkeys who show affection for a surrogate mother in response to tactile comfort."

The nerve system continues to function throughout life, underscoring the importance of such comfort. While the thicker nerve fibers that communicate contact information are more densely packed into areas such as the palm, the thinner nerves are found on hairy areas of the skin such as the forearm.

"Their functional role is below the level of consciousness and has to do with the emotional aspects of touch -- like the pleasure of touch," lead scientist Hakan Olausson, a neurophysiologist at the Sahlgrenska University Hospital in Goteborg, Sweden, said in a telephone interview. "The fast fibers indicate when we are touched and how strong the touch is. [The slow fibers] signal the fine aspects of touch."