The brain's job is simple: process information and regulate energy.
The information comes from both internal and external signals. The body checks itself. What is the heart doing? What about the lungs? There are feedback loops in every part of the body, including for breathing, the stomach and intestinal system and muscles. There are also critical probes measuring the brain’s own emotional heat.
The five senses are our external monitors: vision, hearing, smell, taste and touch. Humans depend a great deal on our visional input. We see shapes, movement and color. The brain transforms the nerve impulses to interpret mountains, a running child or the color of one’s skin. However, a peregrine falcon or any bird of prey sees eight times more clearly.
We listen for a predator rustling the grass, laughter, music or a baby’s cry in the night. Depending on the sound, we manage our energy differently. For an approaching beast, we rev up all the strength we have. When there is joy and song, we may relax or dance. For a baby, we move to soothe.
It is sobering that the greater wax moth hears at a range 15 times higher than we do.
Smelling permits the detection of something foul or fertile. There is a wired instinctive repulsion to the putrid odor of rotting. Any infant will grimace. We are attracted to mates by the pheromones we may not even consciously appreciate. Embarrassingly, bears, elephants and male silk moths all stomp our feeble species in the olfactory Olympics.
Tasting capacity or gustation shows up in those reality cooking contests when the participants have to name all the ingredients of a dish. Lest Iron Chefs get cocky, bottom-dwelling catfish have as many as 175,000 taste buds, while humans have a paltry 10,000.
The tactile system includes pressure, pain, temperature and touch. Our sensitivity varies depending on where the touch occurs. One way to assess this difference is a two-point test. Simply take an ordinary paper clip and uncoil it into two tips. Have the subject close their eyes. Touch with one end or two. Then space the two touches closer and closer. When the test bed is the hand, we are able to distinguish between two pokes even when they are extremely close.
However, turn a person around and do the same thing on his or her back and the results are strikingly different. The distance between the two ends can be significant yet the perception is of only one. The reason is the density of nerve endings. On fingers the sensors are thick, and on the back the fibers are scattered farther apart.
Compared to animals, we are sensorily challenged. In a war of the senses, we would be wiped out. More important than smelling the roses, we need to turn up our sensitivities to our fellow human siblings.
Sensitivity to others is how we position ourselves to them. If we turn our back on someone either literally or figuratively, we are less aware of him or her. We cannot hear them very well. We cannot see them. If they reach out to touch, we may miss the sensation due to the paucity of nerve fibers on our back.
Compared to animals, we are numb and dumb to the world. The additional tragedy is that we are too often equally insensitive to our fellow beings. We fail to see their hurts. We miss hearing their needs. We dismiss any close caress. The powers of our senses will never reach that of a moth, catfish or a hawk, but we can strengthen them by practice.
Look for sorrow to cheer. Listen for cries to comfort. Touch to soothe. Smell sweet aromas, and do not forget gustation.
As Russian poet Boris Pasternak said, "Be so close to those you love that when they weep, you taste salt."
Joseph Cramer, M.D, is a board-certified pediatrician, fellow of the American Academy of Pediatrics, practicing physician for 30 years, a hospitalist at Primary Children Hospital and the University of Utah. He can be reached at email@example.com.